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Key points for lubrication and maintenance of a polishing machine Lubrication and maintenance of the power trowel is the core work to ensure the long-term stable operation of the equipment and prevent sudden failures. The key lies in "using the right oil, finding the right time, doing it on time and using the right method". The following are the specific key points Ⅰ. Core Lubrication Points and Requirements 1. Power trowel the main shaft bearing – the most crucial and frequent Location: The center drive shaft of the pan, usually with 1-2 grease nozzles. Lubricant: High-temperature resistant (≥120℃), extreme pressure lithium-based grease (such as molybdenum disulfide grease) must be used. Ordinary butter must not be used. Method and Cycle It must be carried out after each shift's work (working for 8 to 10 hours). Thoroughly clean the grease nipple and its surroundings. Add until the new grease overflows: Use a grease gun to add until the clean new grease is completely squeezed out from the edge of the bearing seal ring from the old grease. Wipe off the excess grease. Objective: To remove metal shavings and impurities produced by internal wear and ensure that the bearing cavity is filled with new grease. 2. Gearbox/reducer Lubricant: Select the specified type of gear oil (such as SAE 80W-90 GL-4) strictly in accordance with the instructions. Check: Every day, check through the oil window or dipstick whether the oil level is between the upper and lower marks. Replacement cycle First replacement: After the new machine has been running for 20 to 30 hours, remove the running-in debris. Regular replacement: Replace it every 300 to 500 hours of operation or annually thereafter. Key point: Oil change should be carried out when the oil temperature is still hot after the equipment is shut down to ensure that the old oil is completely drained. 3. Traveling wheels and steering mechanism Location: Walking wheel bearing, steering tie rod ball joint, hinge point. Lubricant: The high-temperature resistant lithium-based grease as mentioned above. Cycle: Every 50 hours of operation or once a week. Method: Clean each grease nozzle and add grease until new grease overflows from the gaps. 4. Engine (Gasoline model) Engine oil inspection and replacement Check the oil dipstick before starting every day to ensure the oil level is normal. First replacement: After running for 20 to 30 hours. Regular replacement: Every 100 hours or every quarter. The cycle should be shortened in harsh environments. Air filter maintenance: Regular cleaning. For oil bath air filters, use the dedicated air filter oil as per the instructions. Ⅱ. The Golden Rule for Lubrication Operations Cleaning first: Before filling, be sure to clean the oil nozzle, oil cap and the surrounding area to prevent sand, dust and concrete particles from being brought into the interior. Strict specifications: Different parts should use the specified type of grease/oil products. They must not be mixed or substituted. High-temperature grease is the "life-saving oil" for the main shaft bearings. Squeezing out the old grease: For bearing lubrication, "adding until the new grease overflows" is a necessary step. This is the only effective way to remove contaminants and ensure the lubrication effect. Precise cycle: The maintenance cycle is mainly based on the operating hours (rather than calendar time) and is strictly recorded. Ⅲ. Common Mistakes and Serious Consequences Error: Lubricate the main shaft bearings with ordinary grease. Consequence: The grease melts and leaks away at high temperatures, the bearings dry grind rapidly and burn out at high temperatures, leading to the failure of the entire machine. Error: Only add fat without squeezing out the old fat. Consequence: Metal shavings accumulate in the bearing cavity, forming abrasives, accelerating wear, and causing abnormal noises and jamming. Error: Ignoring the oil level in the gearbox and its replacement. Consequence: Insufficient lubrication of gears and bearings leads to pitting corrosion, broken teeth, and scrapping of the reducer. Error: The spilled grease was not cleaned up after lubrication. Consequence: Grease adsorbs dust to form hard scale, which damages the sealing performance of the oil seal and makes it easier for impurities to invade. Ⅳ. Best Practice Recommendations Create a lubrication chart: Make a simple chart of all lubrication points, oil types and cycles of the equipment, and stick it in a prominent place on the equipment. Equipped with dedicated tools: Use high-quality grease guns and dedicated oiling nozzles to ensure sufficient filling pressure. Record: After each maintenance, record the operating hours and maintenance items to form a traceable maintenance file. Long-term storage and maintenance: Before the equipment is out of use, thoroughly lubricate all lubrication points once. The engine oil should be changed or stabilizers added as per regulations to prevent internal rusting. Summary The lubrication and maintenance of a power trowel essentially involve the continuous confrontation with its harsh working environment (heavy load, high temperature, and much dust). By grasping the two key points of "post-shift high-temperature grease extrusion lubrication" for the main shaft bearings and "regular oil change" for the gearboxes, the vast majority of major mechanical failures can be avoided, significantly extending the service life of the equipment. Note: The parameters provided in this document are for reference only and are not mandatory. Due to differences in technical characteristics between different brands and models of laser levelers, please consult the manufacturer for a suitable solution before actual operation. This reference document assumes no responsibility for any issues arising from failure to follow the manufacturer's instructions.

According to the technical parameters in the product manual of Shandong Vanse Machinery Technology Co., LTD., and in combination with the strict requirements of airport runway construction for extremely high flatness, large area continuous operation, equipment stability and high-precision control systems, the following models are professional choices that can meet the needs and are arranged in the recommended order: Core recommended models These models are the preferred choice for high-standard projects such as airport runways and large industrial floors due to their high power, wide paving, advanced control systems and outstanding stability. YZ40-4E boom-type concrete laser leveling Recommendation reason Maximum paving width: 4 meters, which is the model with the largest width in the manual. It can greatly improve the efficiency of large-area continuous paving and the flatness of the joints. Strong power: 57kW diesel engine, providing sufficient power for high-intensity and long-term continuous construction. Advanced control system: Clearly marked as "Compatible with 3D profiler system". This is the core configuration that meets the extremely high precision requirements of airport runways. The 3D system, controlled by GPS or total stations, can adjust the elevation in real time, perfectly achieving complex slopes and designed elevations, with a precision far exceeding that of traditional single-point lasers. High adaptability: The body can rotate 360 degrees infinitely and be leveled with one click, which can flexibly handle various situations during construction. Professional configuration: Standard cleaning system, soft landing system, etc., to ensure the long-term and stable operation of the equipment. YZ30-4E boom-type concrete laser leveling Recommendation reason Balanced performance: 3.1 meters paving width, achieving a good balance between efficiency and flexibility. Long boom: 6-meter telescopic boom, providing a larger working coverage range and reducing the number of equipment movements. Also compatible with 3D systems: The product features clearly state that it has the technical foundation for achieving high-precision construction. Multi-mode steering: two-wheel, four-wheel, crab steering, providing greater maneuverability in narrow or complex areas. Other applicable models and considerations For the construction of runway accessory areas, taxiways or base layers with slightly lower precision requirements, the following models can also be considered as alternatives: WS550/ YZ28-4S/ WS940/ WS940C ride-on concrete laser leveling, among which WS940C also supports 3D system construction Key Supporting facilities and suggestions for airport runway construction A 3D control system must be used: No matter which model is chosen, it is necessary to select or confirm its compatibility and actually install a high-precision 3D intelligent paving control system. This is the technical guarantee for achieving millimeter-level accuracy in the slope and elevation of the longitudinal and transverse slopes of airport runways. Give priority to the Boom Type model: The boom type leveling does not rely on formwork. It can control the paver head through laser or 3D signals, achieving large-scale seamless continuous operation and fundamentally reducing construction joints. This is the key to ensuring the overall flatness of the runway. Equipment stability and reliability: Airport runway construction is often characterized by tight schedules and high intensity. Particular attention should be paid to the: Engine brand and power (such as Yanmar, Kubota). Reliability of the hydraulic system. Strength of structural components. Comprehensive construction plan Concrete proportioning and conveying: It needs to be used in conjunction with high-efficiency concrete pavers (such as the BL-360 concrete distributor in the product manual) to achieve rapid and uniform sprouting. Subsequent process connection: After leveling, a large ride-on power trowel (such as VS836/VS1046) should be immediately used for finishing to meet the final density and wear resistance requirements of the runway surface. Joint treatment: The Armour joints of the runway need to be professionally treated with high-performance Armour joints (such as AFJ type, S type) to protect the edge of the runway and transfer the load. Conclusion For the high-standard construction of the main surface layer of airport runways, the YZ40-4E is highly recommended. Its maximum paving width and powerful performance make it most suitable for large-scale and efficient operations. The next recommendation is the YZ30-4E, which has obvious advantages in terms of mobility and coverage. The most crucial point is to ensure that the selected model is equipped with and actually applies a high-precision 3D intelligent control system. Before making the final decision, it is strongly recommended: Contact Vanse ([email protected]) for more detailed technical solutions and 3D system configuration instructions. Request successful cases and construction data of relevant aircraft models in similar large airports or key infrastructure projects. If conditions permit, arrange on-site inspection and equipment demonstration. Only by choosing the right equipment and combining it with scientific construction techniques can the airport runway meet the highest quality standards of being "as smooth as a mirror and sturdy and durable". Note: The parameters provided in this document are for reference only and are not mandatory. Due to differences in technical characteristics between different brands and models of laser levelers, please consult the manufacturer for a suitable solution before actual operation. This reference document assumes no responsibility for any issues arising from failure to follow the manufacturer's instructions.

This is a common malfunction of the power trowel machine (also known as the gloss collector or polishing machine). The engine is normal (it can start and the speed sounds normal), but the brake is weak, does not rotate or rotates slowly. The problem must lie in the power transmission system. The following are systematic diagnostic steps and solutions, arranged in order from simple to complex and from outside to inside. Core diagnostic flowchart Engine normal → The disc does not move/lacks power → Check the power transmission path External/Simple inspection → Drive belt system → Clutch system → Gearbox/main shaft Ⅰ. Quick Self-examination and elimination of External Factors Before disassembling the machine, rule out the following possibilities first Excessive load on the power trowel plate: The concrete has passed its optimal finishing time (final setting), and its strength is too high, causing the power trowel plate to be "stuck". Try lifting the machine or testing it on a less hard ground. The issue with the Angle of the power trowel blade: The installation Angle of the blade is too "flat" (the Angle with the ground is too small), resulting in huge resistance. Adjust the blade to an appropriate Angle (usually 5 to 15 degrees to the ground). Foreign object jamming: Check whether the area beneath the power trowel plate and around the main shaft are jammed by hard objects such as cement blocks or steel bar heads. Ⅱ. Key Diagnosis and Resolution: Three Major Systems System One: Drive Belt (the most common cause) The polishing machine usually uses a belt to transfer the engine power to the clutch or gearbox. Symptoms The engine makes a loud noise when idling, and when wiping the disc, it rotates intermittently or doesn't move at all. When the machine is working, a burnt smell can be detected (due to the belt slipping and rubbing). The speed of the power trowel disc is significantly lower than that of the engine, and it is weak. Diagnostic steps Shutdown inspection: Turn off the engine and check if the belt is broken, fallen off or severely worn (with cracks on the side and a shiny back). Tightness check: Press the middle of the belt forcefully with your fingers. The normal deflection should be around 10-15mm. If it is too loose, it will slip; if it is too tight, it will accelerate wear and cause damage to the bearing. For moderate inspection: Check whether the engine pulley and the driven pulley are on the same plane. Misalignment can cause abnormal wear and detachment of the belt. Solution Replace the belt: Be sure to use the original factory or the specified model belt. Adjust the tightness: Loosen the fixing bolts of the engine base, move the engine position to adjust the tension of the belt, and then retighten the bolts. Calibration and alignment: Inspect and adjust the installation base of the engine or driven wheel. System Two: Centrifugal Clutch (Core Fault Point) Centrifugal clutches are commonly used in power trowels. When the engine reaches a certain speed, the clutch block is thrown out under the action of centrifugal force and combines with the clutch cover to transmit power. Symptoms When the engine is running at low speed, the disc does not rotate. At high speed, it may engage but weakly, or it may not engage at all. When the engine speed changes, there is a "clattering" sound or a metallic friction sound inside, but the power cannot be transmitted out. Diagnostic steps Visual inspection (disassembly required) : Remove the clutch protection cover or the wiping plate. Check the clutch friction block Wear: Whether the friction plate has worn to its limit (exposed metal or extremely thin thickness). Oil stains: Whether contaminated by lubricating oil or grease (causing slippage). Detachment: Whether the friction plate has fallen off from the horseshoe. Check the clutch spring Whether the spring is broken, fallen off or fatigued and deformed. Insufficient spring force can cause the clutch block to fail to be flung out or retracted at the correct speed. Check the inner wall of the clutch cover (drum) Whether the inner wall is smooth or has deep grooves. Oil stains and grooves can both cause slipping. Solution Cleaning: Thoroughly clean all oil stains with carburetor cleaner. Replacement: Replace the worn clutch friction blocks and broken/deformed springs in a complete set. It is recommended that the friction blocks be replaced in pairs. Repair/Replacement: If there are deep grooves on the inner wall of the clutch drum, the assembly needs to be repaired or replaced with a lathe. System Three: Gearbox and Spindle If both the belt and the clutch are functioning properly, the problem may extend to the final stage. Symptoms The engine and clutch work normally, but the main shaft doesn't rotate at all. When the machine is running, there is an abnormal noise (creaking, clicking) from the gearbox. The main shaft can be shaken by hand and there is a distinct gap. Diagnostic steps Check the gear oil: Whether the gearbox is short of oil or has metal debris (the oil is grayish-white). Lack of oil can cause gears and bearings to burn out. Check the gears: Open the gearbox to inspect whether the planetary gears or spur gears have broken teeth or severe wear. Check the bearings: Inspect whether the upper and lower bearings of the main shaft are cracked or stuck. Rotate the main shaft by hand to feel if there is any jamming or abnormal noise. Check the splines/keyways: Whether the splines of the main shaft connected to the trotter or the keyways of the clutch output are worn flat, which may prevent power transmission. Solution Change gear oil: Add gear oil of the specified type and volume. Replace damaged parts: Replace damaged gears, bearings or splined shafts. This usually requires professional maintenance personnel to carry out. Summary and troubleshooting sequence table Serial number Inspection site Possible reasons Solution Priority 1 External and Load The ground is too hard, the blade Angle is poor, and foreign objects are stuck Adjust the Angle and clear the foreign objects High 2 Drive belt Fracture, loosening, wear, misalignment Replace, adjust the tension and correct the alignment High 3 Centrifugal clutch Friction block wear/oil stains, spring breakage Clean and replace the friction blocks and springs High 4 Gearbox Lack of oil, gear damage, bearing damage Refuel and replace gears/bearings In the 5 Main shaft/spline The splines are ground flat and the main shaft is bent Replace the main shaft Low Safety Operation Tips Before any maintenance, be sure to turn off the engine and unplug the high-voltage wires of the spark plugs to prevent accidental start-up. Wait until the engine and exhaust components have completely cooled down before operating. When disassembling, pay attention to the sequence of the parts and take photos for record. When reinstalling, the key bolts need to be tightened as required by the torque. If you are not familiar with the mechanical structure, it is recommended that you contact professional equipment maintenance personnel for handling. In the above order, the vast majority of problems with the power trowel that are "powerless but unable to be utilized" can be identified and resolved. The most common and top-priority items to be inspected are belts and clutches. Note: The parameters provided in this document are for reference only and are not mandatory. Due to differences in technical characteristics between different brands and models of laser levelers, please consult the manufacturer for a suitable solution before actual operation. This reference document assumes no responsibility for any issues arising from failure to follow the manufacturer's instructions.

The success of special floors (such as epoxy floors and curing agent floors) is "70% dependent on the base layer and 30% on the materials". The quality and treatment of the base concrete's smoothing are the key prerequisites for determining the final floor effect and lifespan. The following are the detailed requirements and treatment procedures for the concrete base layer before grinding. Core principle The objective of the base concrete is to provide a "canvas" that is of high strength, dense and smooth, dry and clean, and free of defects. Ⅰ. Requirements for Concrete Base Smoothing (Pouring Stage) This refers to the operation carried out using a mechanical trowel during the period from the initial setting to the final setting of concrete. The requirements are far higher than those for ordinary concrete floors. Concrete grade and proportion The strength should not be lower than C25, and it is recommended to be above C30. The water-cement ratio should be low (generally ≤0.5) to reduce bleeding, enhance surface strength and wear resistance. The aggregate (sand and gravel) particle size is moderate and the mud content is low, ensuring a fine surface. Pouring and vibration It is necessary to vibrate thoroughly to expel air bubbles and ensure that the concrete is dense, free of voids and honeycombs. Key step: Polishing process Preliminary leveling: After the concrete is laid, a laser screed or a scraper is used for initial leveling. Bleeding treatment: Allow the free water on the surface to fully evaporate. Start the operation before the initial setting (when the depth of the human footprint is about 2-3mm). The first coat of troweling (lifting the slurry) : Use a circular troweling machine to run at low speed to lift and smooth the surface slurry, filling in local unevenness. The second coat of smoothing (compaction) : When the surface moisture has further evaporated (and the footprints left by a person standing on it are very shallow), switch to a trowel blade (iron plate), run at medium speed, and apply in a cross direction to compact and smooth the surface. The third coat of polishing (fine polishing) : Before the concrete has finally set (with no standing water on the surface and slight marks when pressed by fingers), use a trowel blade to finely grind at high speed. This step is of vital importance as it can significantly enhance the surface density and flatness, resulting in a smooth and uniform hardened surface. Flatness requirement When using a 2-meter straightedge for inspection, the gap should not exceed 3mm. The high-standard project requirement is ≤2mm. The overall slope should comply with the design requirements and there should be no water accumulation areas. Maintenance requirements After the smoothing is completed, full curing must be carried out immediately (it is recommended to cover with plastic film or spray a special curing agent) to prevent cracking due to excessive evaporation of water. The curing period should be no less than 7 days, with 14 to 28 days being the best. Ⅱ. Base Inspection and Treatment Before Grinding (Grinding Construction Stage) Even a well-polished floor must undergo strict inspection and targeted treatment before grinding. This stage is usually carried out after the concrete pouring and curing are completed (at least 28 days after the strength meets the standard). Comprehensive inspection Strength: Tested by a rebound tester, the surface compressive strength is ≥ 25MPa. For curing agent floors, the higher the strength of the base layer, the better the final effect. Moisture content: Detected using an electronic hygrometer. Epoxy flooring has strict requirements (the moisture content of the base layer should be ≤ 4%, or as per the requirements of the material supplier). The curing agent floor has a relatively high tolerance for moisture, but it must not have standing water either. Flatness: Check again with a 2-meter straightedge and mark the areas that exceed the standard. Defect inspection: Carefully examine for hollowing (by tapping with a small hammer), cracks, oil stains, floating slurry, cement lumps, exposed steel bar ends, etc. Key processing procedures Cleaning: Thoroughly sweep the floor and use an industrial vacuum cleaner to suck up all dust and sand particles. Hollowing and Defect repair Remove all hollow and loose parts. V-shaped grooves should be made for non-structural cracks, and they should be filled and repaired with high-strength non-shrinking epoxy resin or polymer cement mortar. The exposed ends of the steel bars on the ground should be cut to at least 3mm below the surface, then treated with anti-rust paint and filled with repair mortar. For local pits or height differences, they should be leveled with a professional grinding machine or milling machine and then filled with matching repair materials. Oil stain treatment: For oil stains, they must be thoroughly removed. Light oil stains can be wiped with special cleaning agents or solvents. Severely penetrating oil stains should be treated with fire roasting, milling or special degreasing agents. If necessary, the contaminated concrete should be knocked off and re-poured. Floating slurry and weak layer treatment: This is one of the core purposes of grinding. Even on a well-polished floor, there may still be a layer of cement slurry film (floating slurry) with relatively low strength formed due to bleeding on the surface. The primary task of the grinding machine is to remove this layer of floating Summary comparison table Stage Key requirements for epoxy flooring Key requirements for concrete hardener flooring Polishing requirements Extremely high. The denser and flatter the surface is, the better the adhesion of the epoxy coating will be and the brighter and smoother the coating effect will be. It needs to be polished to perfection. High. The surface density directly affects the uniformity of the curing agent's penetration and the final hardening effect, and it also requires a fine finish. Strength requirements High (≥C25). The base layer is solid, and the coating is not prone to cracking due to base layer cracking. Very high (it is recommended to be ≥C30). The strength of the base layer is the foundation of the final strength, and the curing agent is an addition reaction. Moisture content requirement Extremely strict (≤4%). Moisture can cause the epoxy coating to bubble and delaminate. It should be relatively loose, but the ground must be dry and free of standing water. The curing agent can react with the hydration products of cement. Pretreatment before grinding The key points are absolute dryness, dust-free, oil-free and high flatness. The floating slurry layer must be removed to ensure adhesion. The key points are to remove the floating slurry, open the pores, deal with the defects and ensure the surface is smooth. Grinding opens up channels for the penetration of curing agents. Grinding particle size Usually, grinding to 80-120 mesh is sufficient to provide adequate roughness (anchor texture) for the epoxy primer. Usually, a coarser finish (such as starting at 30-40 mesh) is required to open up the surface, followed by multiple grinding processes to a higher mesh count (such as 1000-3000 mesh) for a brighter finish. Final suggestion Communication in advance: Before the concrete pouring, the floor construction unit should conduct a detailed technical briefing with the general contractor of the civil engineering, clearly defining the plastering standards and curing requirements. On-site supervision: The floor construction party should send personnel to supervise and guide during the concrete smoothing stage. System treatment: Regard the base treatment as a systematic project, from pouring to curing, and then to the inspection and repair before grinding, each step is interlinked and no step can be omitted. Professional assessment: For the renovation of old floors, a comprehensive assessment must be conducted by professionals before grinding, and a detailed treatment plan should be formulated. Only by following the above requirements and procedures can a perfect foundation be laid for the subsequent epoxy resin coating or concrete sealant and hardener construction, thereby creating a high-performance and long-life high-quality floor. Note: The parameters provided in this document are for reference only and are not mandatory. Due to differences in technical characteristics between different brands and models of laser levelers, please consult the manufacturer for a suitable solution before actual operation. This reference document assumes no responsibility for any issues arising from failure to follow the manufacturer's instructions.

The occurrence of surface defects in concrete is often not caused by a single factor, but rather the result of the combined effects of materials, the environment, construction techniques and equipment operation. As the final key process in floor forming, the operation mode of the power trowel machine directly affects the final quality of the surface. The following is a detailed analysis of the causes of common surface defects, with a focus on elaborating their correlation with the operation of the power trowel machine. Core correlation logic The function of the power trowel machine is to compact, lift the slurry and smooth the surface of the concrete through the high-speed rotating power trowel. Improper operation can directly lead to or exacerbate the following problems: Disrupt the uniformity of concrete (such as bleeding and segregation). Change the water-cement ratio on the surface layer (such as by sprinkling water and grinding). Introduce inappropriate stress (premature heavy-load operation leads to cracking). It is impossible to effectively make up for the deficiencies of the previous processes. Analysis of the Correlation between Common Surface Defects and the Operation of Polishing Machines 1. The surface shows signs of sanding and powdering Defect description: Insufficient surface strength, loose cement and fine sand shedding. The fundamental cause The water-cement ratio on the surface is too high (bleeding or excessive watering). The cement grade is insufficient or the quality is poor. Improper maintenance causes the surface to lose water too quickly. The correlation with the operation of the power trowel machine (main reason) : Premature operation: Start smoothing the concrete when there is still a large amount of bleeding, removing the cement slurry and leaving only the sand. Excessive water sprinkling on flour grinding: This is the most fatal operation. When the surface is dry, workers sprinkle water to save effort, which greatly increases the water-cement ratio of the surface layer and seriously reduces the surface strength. The timing of power trowel is too late: The concrete has already begun to set, and the power trowel cannot effectively lift and compact the slurry. It merely "scraped" once and failed to bring the cement slurry to the surface. Improper blade Angle or severe wear: Unable to effectively compact the surface layer. 2. Surface cracking/plastic shrinkage cracks Defect description: Irregular, shallow and fine reticular cracks appear on the surface. The fundamental cause The evaporation rate of surface moisture is greater than the bleeding rate (in high-temperature, windy, and low-humidity environments). Concrete itself has poor bleeding. Correlation with the operation of the power trowel machine: Failure to seal the surface in time: The first (bottom grinding) process of the power trowel is of vital importance. That is, under the aforementioned environmental conditions, when the concrete can reach the person mentioned above (about 25-30mm deep footprint), the power trowel should be used in conjunction with the disc to lift the slurry and seal it in time to prevent the water from evaporating too quickly. If the waiting time is too long and the crack has already formed, it will be of no avail to smooth it out. Improper operation aggravates water loss: The high-speed rotating power trowel generates heat by rubbing against the concrete and accelerates water evaporation under the influence of air flow. In harsh environments, attention should be paid to operational efficiency. After completing a certain area, timely maintenance should be carried out. 3. Uneven surface/Poor waviness Defect description: The ground is overall uneven, with a "ladle" or "wavy" feeling. The fundamental cause The initial flatness control of the laser screed is not good. The slump of the concrete is uneven. The correlation with the operation of the power trowel machine (main reason) : The operation method is not professional Without adopting the "horizontal and vertical cross" method: Always grinding in the same direction, it is easy to form a "furrow" effect, resulting in strip-shaped protrusions. If the machine body stays in one position for too long, the weight of the power trowel and vibration will cause that area to slightly sink, forming a "dent". Improper timing of raising or lowering the arm: When changing direction, failing to lift or lower the power trowel plate/power trowel smoothly can result in knife marks or local protrusions. Uneven walking speed: The inconsistent speed leads to different degrees of compaction, resulting in color differences and slight height differences. 4. Surface color difference Defect description: The ground color varies in depth. The fundamental cause The raw materials (especially cement) vary from batch to batch. The pouring interval is too long, resulting in cold joints. Correlation with the operation of the power trowel machine: The timing of the finishing is not accurately grasped: There are slight differences in the initial setting time of concrete in different areas. If the operator stops the light in some areas when it is still bleeding (the color is bright), while in others when it is close to final setting (the color is dark), a color difference will occur. Repeatedly grinding the same area: Repeatedly grinding a relatively wet local area will result in excessive slurry in that area and a color that is different from other areas. Uneven watering: If water is sprinkled locally to grind the surface, it will directly cause the water-cement ratio in that area to be different, resulting in a lighter and whiter color. 5. Hollowing/peeling Defect description: The surface-hardened layer has detached from the lower layer. The fundamental cause The surface is over-polished, forming a dense but fragile cement paste layer, which is inconsistent with the contraction of the lower layer. The lower layer of concrete has severe bleeding, forming a water film and weakening the interlayer bonding force. The correlation with the operation of the power trowel machine (key reason) : Excessive finishing: Forcing the use of a power trowel machine after the concrete has r The correct construction guide based on the operation of the power trowel machine To avoid the above-mentioned defects, the operation of the power trowel machine should follow the principle of "timely and moderate". Operation stage Key points for correct operation Purpose and avoidable defects Initial grinding (pulp extraction Timing: When the foot sinks by about 3 to 5mm. Objective: To remove the slurry on the surface of the aggregate and seal the surface. Tool: Install the disc. Avoid: Cracking and sanding. Technique: Move at a constant speed and cover the entire area. Smooth (finely grind Timing: After initial grinding, the surface is free of moisture and has a matte color. Objective: To eliminate scratches, fine deviations and further compact. Tool: Replace with a fine power trowel (power trowel). Avoid: poor waviness and color difference. Technique: Use the horizontal and vertical intersection method, maintain a uniform speed, and lift the arm to press down steadily. Fine grinding (finishing) Timing: After smoothing, there is almost no trace left when stepped on (close to final setting). Objective: To obtain a dense and smooth surface. Tool: The same or thinner spatula, adjusted to a small Angle. Avoid: hollowing, color difference, and cracks caused by excessive dimming. Technique: Gentle and steady, succeed in one go, avoid repetition. The Golden Rule 1. No sprinkling water! If the surface does lose water prematurely, a very small amount of water should be sprayed with a sprayer, and this should be done before the initial grinding. Eliminate most surface defects fundamentally. 2. Timing is the key! Closely observe the setting state of the concrete rather than the rigid time. 3. "Intersection" and "uniformity" are at the core of flatness. Summary An excellent power trowel operator is not only a machine operator but also an "observer" and "manager" of the concrete setting process. He needs to understand the fundamental principles of materials science, and through precise operation timing and proficient techniques, transform the solid foundation created by the laser screed into a high-quality floor with high strength, high flatness and no defects. Note: The parameters provided in this document are for reference only and are not mandatory. Due to differences in technical characteristics between different brands and models of laser levelers, please consult the manufacturer for a suitable solution before actual operation. This reference document assumes no responsibility for any issues arising from failure to follow the manufacturer's instructions.

The walking system of the Concrete Laser Leveling is one of its core functions. Once it malfunctions, it will directly affect the construction efficiency and the flatness of the floor. The following is a systematic review of the diagnostic steps and solutions for abnormal walking systems for you. Ⅰ. Classification of Fault Phenomena First, make a preliminary classification based on different fault phenomena: Completely unable to walk: The leveling machine is completely stationary. Weak walking/Slow speed: Can walk, but lacks power and cannot reach the set speed. Unstable walking/shaking: Stammering during walking or severe shaking of the body. Abnormal walking on one side: One side is normal, while the other side is motionless, weak or in the wrong direction. Walking deviation: Unable to walk in a straight line, automatically veers to one side. Ⅱ. Systematic Diagnostic Process and Solutions Follow the principle of conducting the investigation from simple to complex and from the outside to the inside. Step 1: Preliminary appearance and basic inspection Emergency stop switch and mode selection Diagnosis: Check whether the emergency stop switch on the operation console or remote control has been pressed and whether the working mode (such as manual/automatic) has been selected correctly. Solution: Release the emergency stop switch and select the correct working mode. Power supply and line connection: Diagnosis: Check whether the main power switch and battery terminals are loose, corroded or have insufficient power (for battery-powered models). Check whether the plugs at the main control cabinet and the walking motor are loose. Solution: Tighten all terminal blocks, clean the battery terminals, charge the battery or replace it. Make sure all the plugs are securely connected. Jamming of mechanical transmission components Diagnosis: Check whether the walking wheels (tracks), drive shafts, chains or gears are jammed by solidified cement, crushed stones or other foreign objects. ** Solution ** : Immediately stop the machine and thoroughly clear all obstructions. Check the lubrication condition of the chain or gearbox and add or replace the specified grease if necessary. Step 2: Hydraulic System Diagnosis (Common Fault Points) If there are no issues found during the initial inspection, focus on checking the hydraulic system. Hydraulic oil level and oil quality Diagnosis: Insufficient hydraulic oil can cause the pump to run dry, resulting in weak or no movement during movement. Deteriorated oil (turning black, foaming, or having metal shavings) can damage hydraulic components. Solution: Check the oil level while the machine is shut down and replenish it to the specified mark. If the oil quality is substandard, the hydraulic oil and filter element of the original factory-specified model must be completely replaced. Walking motor and drive pump Diagnosis (Unilateral abnormality) : If only one side of the walking is abnormal, you can try to swap the hydraulic pipelines of the walking motors on both sides. If the fault phenomenon then shifts to the other side, it indicates that the walking motor or pump on the original side is faulty. Solution: Please contact professional maintenance personnel. It may be necessary to inspect or replace the walking motor, variable pump or related control valves. This job requires professional knowledge and tools. Do not disassemble it by yourself. Hydraulic system pressure Diagnosis: Use a hydraulic pressure gauge to check whether the overflow pressure of the main safety valve and the walking circuit of the system has reached the specified value. Low pressure can lead to weakness when walking. Solution: Have a professional technician adjust the corresponding relief valve to the standard pressure. Do not adjust it at will, otherwise the hydraulic system may be damaged. Step 3: Control system and sensor diagnosis For laser leveling machines that adopt advanced control systems. Laser control system Diagnosis: Check whether the laser transmitter is working properly and whether the signal is stable. Check whether the laser receiver on the leveler is clean and firmly installed. Signal loss or instability can cause the machine to move in confusion or stop. Solution: Ensure that the laser transmitter is stably set up and the signal covers the entire construction area. Clean the laser receiver rod and sensor head. Recalibrate the system. Control module and sensor Diagnosis: Observe whether there are any fault code alarms on the control panel. Check whether the walking speed sensor, Angle sensor, etc. are damaged or the circuit is disconnected. Solution: Check the cause according to the fault code manual. Check and plug in the sensor wiring tightly. Replace it if any damage is found. Remote control/line controller Diagnosis: Weak signal, insufficient battery power or internal faults of the remote control can cause instructions to fail to be sent correctly, resulting in abnormal walking. Solution: Check the battery level of the remote control and try frequency matching or restarting. If possible, switch to the line control mode for comparative testing to determine whether the problem lies with the machine or the remote control. Ⅲ. Quick Reference Table of Common Fault Phenomena and Targeted Solutions Fault phenomenon Possible reasons Solution Completely unable to walk 1. The emergency stop switch is activated 1. Release the emergency stop switch 2. Main power supply disconnected/Battery discharged 2. Check and connect the power supply/charge 3. Failure of the main hydraulic pump 3. Overhaul the main pump 4. Control signal interruption 4. Check the remote control, receiver and wiring Weakness in walking The hydraulic oil level is too low or the oil quality is poor 1. Add or change the oil 2. The hydraulic filter element is clogged 2. Replace the hydraulic filter element 3. System pressure is too low 3. Adjust the pressure by professionals 4. Leakage inside the walking motor or pump 4. Inspect or replace hydraulic components One side not moving/weak The track/wheel on this side is mechanically jammed 1. Remove foreign objects 2. The walking motor on this side is faulty 2. Swap the hydraulic pipelines for testing and then carry out the repair after confirmation 3. The valve core of the control valve on this side is stuck or damaged 3. Clean or replace the valve assembly 4. The speed sensor on this side is faulty 4. Check or replace the sensor Shaking/Unstable walking There is air in the hydraulic system 1. Perform the exhaust operation 2. The signal of the flow/speed sensor is unstable 2. Check the sensors and circuits 3. Hydraulic oil contamination leads to discontinuous valve core operation 3. Replace the hydraulic oil and filter element Walking off course 1. The laser signal is inaccurate Recalibrate the laser system 2. The tension of the tracks on both sides is inconsistent 2. Adjust the tracks to the same tension 3. The bearing of one of the walking wheels is damaged 3. Replace the damaged bearing 4. Calibration error of the control system 4. Re-perform the walking calibration Ⅳ. Safety Precautions and Daily Maintenance Before starting work every day, check the hydraulic oil level, battery power, whether there are any foreign objects in the walking mechanism, and whether all sensors are clean. Regular maintenance: Replace the hydraulic oil and filter elements strictly in accordance with the maintenance manual, and lubricate all bearings and chains. Standard operation: Avoid driving at high speed on overly bumpy or foreign object surfaces, and turn smoothly. Timely cleaning: After each day's construction, it is essential to thoroughly clean the machine before the concrete solidifies, especially the traveling wheels and sensor parts. Important Note: The hydraulic and control systems are highly precise. When issues involve the disassembly of internal components and pressure adjustment, it is strongly recommended to contact the equipment manufacturer or an authorized professional service engineer for handling to avoid causing greater damage or safety accidents. Note: The parameters provided in this document are for reference only and are not mandatory. Due to differences in technical characteristics between different brands and models of laser levelers, please consult the manufacturer for a suitable solution before actual operation. This reference document assumes no responsibility for any issues arising from failure to follow the manufacturer's instructions.

Let's focus on discussing how to prevent surface defects of concrete by standardizing the operation of power trowels. The following is a summary of targeted preventive measures based on common defects, aiming to provide a clear operational guide for construction. A Comprehensive overview of preventive measures for operating a power trowel for concrete surface defects Defect type Core preventive measures (Operating Angle of the power trowel machine) Detailed explanation of key operation points 1. The surface shows signs of sanding and powdering No watering is allowed. Seize the opportunity for the initial grinding 1. Iron rule: Do not sprinkle water when grinding flour: This is the first principle for preventing sanding. When the surface becomes dry, wait for the right moment to polish it instead of sprinkling water. 2. The timing of initial grinding is accurate: When the concrete can withstand a person's foot subsidence of about 3-5mm, immediately use a disc for initial grinding to lift the slurry and bring the cement slurry to the surface. 2. Cracking/plastic shrinkage cracks Timely initial grinding and sealing for efficient operation 1. Seal the surface as early as possible: In high-temperature and windy weather, concrete may lose water before it begins to set. Once it is accessible to people, immediately use the disc of the power trowel to quickly lift the slurry to form a sealing layer and lock in the moisture. 2. Continuous operation: Plan the operation sequence well to ensure that the power trowel machine can continuously and efficiently complete the initial grinding and sealing of one area, avoiding surface water loss and cracking due to excessive intervals. 3. Uneven surface/Poor waviness Standardize the operation techniques and maintain uniformity 1. Use the cross-grinding method: The grinding paths of two adjacent times should be perpendicular to each other (one horizontally and one vertically) to avoid the formation of furrows due to unidirectional grinding. 2. Uniform and stable operation: Keep the machine moving at a constant speed and avoid sudden acceleration and deceleration. 3. Reduce downtime: It is strictly prohibited to leave the machine in one place for a long time to prevent local excessive vibration and subsidence. 4. Smooth steering: When turning or making a U-turn, lift the power trowel steadily to avoid forced twisting that may cause tool marks and bulges. 4. Surface color difference Unify the timing of light collection to avoid excessive grinding in certain areas 1. Unify the state of the working surface: Wait until the concrete setting state of the entire working surface is basically consistent (all reaching the required dryness and wetness for finishing) before starting the finishing. 2. "One-time Pass" principle: During the fine grinding and finishing stage, strive for success in one go and avoid repeatedly grinding local areas. For areas that truly need to be supplemented, they should be briefly touched upon. 5. Hollowing/peeling Avoid excessive light collection and prevent operation during bleeding 1. Identify the final setting point: When the sound of the power trowel rubbing against the ground becomes clear and the ground's reflectivity weakens, the operation should be stopped immediately. Forced light collection will damage the structure and cause delamination. 2. Do not work on standing water: When there is bleeding or accumulated water on the surface, the power trowel must not be used. The water should be removed first using a vacuum suction hose or rubber hose. Standardized Operating Procedures for power trowel (Preventive Operating Guidelines) To ensure the implementation of preventive measures, the following standardized operating procedures must be followed: Phase One: Initial grinding (Slurry extraction and sealing) Timing judgment: When the foot sinks by 25-30mm (or when a finger presses and leaves a fingerprint of 10-15mm). This is a key window for preventing cracking. Tool: Install the disc. Operation The machine maintains a steady speed. Perform the first grinding in the same direction, overlapping the previous one-third of the disc diameter. Objective: Slightly press down the coarser aggregates to bring the cement slurry to the surface, seal the surface evaporation channels, and provide a smooth foundation for subsequent fine grinding. Phase Two: Smoothing (Fine grinding and compaction) Timing judgment: After the initial grinding, the surface footprints disappear, there is no free water, and it presents a matte state. Tool: Replace with a coarse power trowel (power trowel). Operation Adopt the crossover method: for instance, walk vertically for the first time and horizontally for the second time. This is the core to ensuring flatness. Adjust the Angle of the spatula to a slight upward Angle (about 1-3°), mainly to smooth it out. Objective: To eliminate the marks left by the disc, further compact the surface, and eliminate minor height differences. Phase Three: Fine Grinding (Finishing) Timing judgment: When stepped on, there is almost no trace left. When the spatula passes over the surface, the trace is slight and can close quickly. Tool: The same or thinner spatula. Operation The Angle of the spatula can be adjusted to be flatter or slightly upward. The operation should be gentle and uniform, striving for success in one attempt. Objective: To make the surface particles more closely arranged to achieve a dense and smooth effect. At this point, any unnecessary operation is harmful. Summary: The core principle of prevention Timing is more important than anything else: The greatest skill of an operator is to accurately judge the setting state of concrete. Moisture is a double-edged sword: internal moisture is the source of strength, while surface excess moisture is the root cause of defects. Never sprinkle water. Uniformity is the foundation of flatness: maintaining a constant speed, crossing, and reducing pauses are the only ways to achieve high flatness. Know when to stop: Dimming is not the more times the better. Excessive dimming is a direct cause of hollowing and cracking. By integrating the above preventive measures and standardized procedures throughout the entire construction process, surface defects caused by improper operation of the power trowel can be minimized to the greatest extent, thereby effectively improving the final quality of the concrete floor. Note: The parameters provided in this document are for reference only and are not mandatory. Due to differences in technical characteristics between different brands and models of laser levelers, please consult the manufacturer for a suitable solution before actual operation. This reference document assumes no responsibility for any issues arising from failure to follow the manufacturer's instructions.

The problem of sudden deviation in the leveling accuracy of the concrete Laser Leveling during the construction process is an extremely urgent situation. The following is a systematic guide for troubleshooting, calibration and repair aimed at helping you resume construction quickly. Sudden deviation in the leveling accuracy of the concrete Laser Leveling: Rapid calibration and repair When there is a sudden deviation in accuracy, please follow the principle of "from the outside to the inside and from the easy to the difficult" to conduct a systematic investigation. Step 1: Immediately shut down the machine and conduct a preliminary inspection (quick troubleshooting within 5 minutes) Check the laser signal source Stability: Immediately check whether the tripod of the laser emitter has been knocked over or settled by personnel or equipment. Battery power: Make sure the laser is fully charged. Low battery power may cause unstable beam. Cleanliness: Quickly check if there are any mud spots or dust on the light-emitting lens of the laser emitter, and clean it with special lens cleaning paper. Inspect the body of the leveling machine Receiver rod: Check whether the mast on which the receiver is installed has been bent or loosened. Receiver cleaning: Check if the surface of the receiver sensor is contaminated by cement slurry or dust, and clean it immediately. Scraper and flattening head: Check whether the bottom plate of the flattening head and the scraper have severe wear or concrete accumulation, as this can cause physical scratches and affect the perception accuracy. Step 2: Systematic and in-depth investigation and rapid calibration If the initial inspection does not solve the problem, please perform the following in-depth operations. 1. Calibration verification of the laser system Manual rotation test: Manually and slowly rotate the laser emitter 360 degrees to observe whether the signals of the leveler receiver are consistent and stable in all directions. If there is a continuous deviation in a certain direction, it might be that the transmitter's reference is inaccurate. Check the reference height: Use a tower ruler or steel tape measure to measure whether the reference height set by the laser emitter is consistent with the actual height of the ground control point, and eliminate errors in the reference setting. 2. Mechanical inspection of the leveling machine body Hydraulic system pressure: Check whether the hydraulic pressure of the lifting mechanism is normal and stable. Insufficient pressure can cause the flat head to "sink" in the concrete, resulting in overly deep scratches. Sensor and actuator connection: Check whether the mechanical or electrical connection between the receiver signal and the hydraulic valve is loose or damaged. Try to conduct a "manual/automatic" switching test. In the automatic mode, slightly cover the receiver manually and observe whether the flat head responds quickly to rise and fall. If there is no response or the response is slow, it indicates a fault in the signal transmission or hydraulic control system. 3. Perform rapid on-site calibration (key step) Most modern laser screeners are equipped with "quick calibration" or "learning" functions. Please refer to the manual of your equipment (such as YZ30-4E from Shandong Vanse Technology) for operation. The general process is as follows: Enter calibration mode: Go to the calibration menu on the control panel. Locate the high and low points: Turn on the Leveling to a known reference plane (or have the laser emitter sweep out a plane), and move the receivers to a known "high point" (with the display bar at the top) and a "low point" (with the display bar at the bottom) respectively. Data collection: Confirm the position at each point and let the machine record the corresponding relationship between the Angle of the laser signal received at this time and the height of the flattening head. Complete and test: Save the calibration data and exit the menu. Move the machine on the reference plane and observe whether it can be stably maintained at the "zero position" (with the green light constantly on). Step 3: Emergency repair measures and decision-making If obvious mechanical faults such as mast bending or hydraulic cylinder leakage are found, use should be stopped immediately and maintenance personnel should be contacted. Electronic system failure: If it is highly suspected after investigation that the fault lies within the control mainboard, receiver or laser transmitter, the "replacement method" should be adopted. Replacing the spare laser transmitter or receiver for testing is the fastest way to locate the source of the fault. Activate the backup plan: When the fault cannot be immediately eliminated and the construction task is urgent, it can be used as a temporary measure to switch to manual mode. Relying on the experience of skilled operators, the current section construction can be completed, and the equipment can be moved aside for maintenance to avoid prolonged downtime. Summary: Quick Action Checklist Stop: Immediately shut down the machine to prevent the defect from expanding. Look: Conduct a quick visual inspection of the laser, receiver, and flattening head for any obvious abnormalities. Clean: Clean all optical and mechanical components. Check: Verify the laser reference and the response of the leveling machine. Calibration: Carry out on-site rapid calibration procedures. Replace: Conduct replacement tests using spare parts. If the above steps are ineffective, contact the technical support of the equipment supplier immediately. Following this process quickly and calmly can minimize downtime to the greatest extent and ensure the quality and efficiency of construction. Regular preventive maintenance of equipment is the best way to avoid such unexpected problems. Note: The parameters provided in this document are for reference only and are not mandatory. Due to differences in technical characteristics between different brands and models of laser levelers, please consult the manufacturer for a suitable solution before actual operation. This reference document assumes no responsibility for any issues arising from failure to follow the manufacturer's instructions.

The following is a detailed answer to the analysis of the causes of unstable laser signals in Concrete Laser Leveling and the corresponding treatment measures. Analysis of the Causes of Unstable Laser Signals in Concrete Laser Leveling and Treatment Measures Unstable laser signals are one of the common faults in the construction of Concrete Laser Leveling, which will directly lead to a decrease in the leveling accuracy and affect the flatness and quality of the floor. It is of vital importance to quickly locate and solve problems. I. Cause Analysis The main causes of unstable laser signals come from four aspects: the laser emitter, the signal receiver, the external environment and the machinery itself. 1. Laser emitter system Power supply issue: Insufficient battery power or poor contact of the power adapter leads to unstable power supply to the laser and fluctuations in output power. Laser itself malfunction: Aging, damage of the laser module or loosening or contamination of internal optical components (such as lenses) can cause the beam to diverge or drift. Unstable reference point: The tripod of the laser emitter is not stably set up and may slightly move or sink under the influence of wind or human touch. Automatic calibration failure: The calibration system of the transmitter with self-leveling function (such as pendulum, magnetic damping or electronic sensor) malfunctions and cannot maintain a stable level reference. 2. Signal receiver system Power connection issue: The connection cable between the receiver and the main body of the leveler is loose, poorly connected or damaged. Sensor failure: The photoelectric sensor on the receiver is aged, its sensitivity has decreased, or it is covered with dirt (dust, cement slurry), making it impossible to accurately identify the laser signal. Improper installation: The receiver is not correctly installed on the mast, or there is severe vibration at the installation position, which affects signal reception. 3. External environmental interference Strong light interference: The intense sunlight at noon, especially its infrared spectrum, can interfere with the receiver's recognition of laser signals. Obstruction: Temporary obstructions such as scaffolding, personnel, and equipment at the construction site block the laser beam, causing signal discontinuity. Vibration interference: There are large equipment (such as excavators, heavy trucks) operating nearby, or the laser emitter is set up on a platform with obvious vibration, causing the reference optical path to jitter. Atmospheric disturbance: At super-large construction sites, heat waves caused by high ground temperatures can lead to uneven air density, resulting in slight refraction and jitter of laser beams. 4. Problems with the body of the leveling machine Mechanical vibration: If the engine of the Leveling machine operates unsmoothly or the hydraulic system vibrates excessively, the vibration will be transmitted to the receiver, introducing signal noise. Electrical system interference: The generator, frequency converter or high-current circuit of the leveling machine itself generates electromagnetic interference, affecting the sensitive receiver circuit. Ⅱ. Handling Measures Follow the principle of "from simple to complex and from outside to inside" in the investigation. Step 1: Quick inspection and basic processing Check the power supply: Ensure that the laser emitter is fully charged and all power connections are firm and reliable. Clean and inspect optical components: Use dedicated lens cleaning paper to clean the output lens of the laser emitter and the sensor window of the receiver. Stable reference: Confirm that the laser emitter tripod is firmly set up on a solid floor and kept away from vibration sources. Use counterweights to stabilize the tripod when necessary. Eliminate environmental interference Shading: Install a sunshade on the receiver to prevent direct exposure to strong light. Obstacle clearance: Inspect and clear all possible obstacles along the laser propagation path. Vibration avoidance: Suspend operations that generate strong vibrations nearby or move the position of the laser emitter. Step 2: System diagnosis and targeted maintenance 5. Restart the system: Turn off the power of the laser emitter and the leveler, wait for one minute, and then restart to reset the electronic system. 6. Calibration check Manually rotate the transmitter to check if it can provide a stable signal throughout the entire 360-degree range. Use professional tools to check whether the automatic leveling function of the laser emitter is normal. If necessary, send it for repair and calibration. 7. Substitution method test Install the receiver on another confirmed normal level machine for testing. If the problem persists, it indicates that the receiver is faulty. Replace it with a confirmed normal laser emitter. If the problem is solved, the original emitter needs to be repaired. 8. Inspect the cables and connections: Carefully check all the cables from the receiver to the main controller for any signs of compression, wear or breakage, and reinsert all the connectors. 9. Seek professional support: If none of the above steps can solve the problem, it is very likely that there is a hard fault with the electronic components inside the laser or the receiver. At this point, you should immediately contact the after-sales service department of the equipment manufacturer (such as Shandong Wansai Technology) for diagnosis and repair by professional technicians. Do not disassemble the core components by yourself. Summary and preventive suggestions Regular maintenance: Clean and calibrate the laser transmitter and receiver regularly in accordance with the operation manual. Standard operation: Set up and move the equipment correctly to avoid violent impacts. On-site investigation: Observe the on-site environment before construction, plan the installation position of the laser emitter in advance, and avoid potential interference sources. Backup equipment: For critical projects, it is recommended to prepare backup laser transmitters or receivers to deal with sudden malfunctions. Through systematic analysis and step-by-step investigation, the problem of unstable laser signals of concrete Laser Leveling machines can be efficiently solved, ensuring the quality and efficiency of construction. Note: The parameters provided in this document are for reference only and are not mandatory. Due to differences in technical characteristics between different brands and models of laser levelers, please consult the manufacturer for a suitable solution before actual operation. This reference document assumes no responsibility for any issues arising from failure to follow the manufacturer's instructions.

There are various methods for basement floor construction. Among them, the construction of diamond sand floor and diamond sand floor with curing agent is favored by many real estate projects due to its economic, wear-resistant, pressure-resistant, anti-pollution and easy-to-clean features. However, improper manufacturing processes can also lead to quality issues and potential risks. This article will respectively introduce the diamond sand wear-resistant floor from the perspective of technology and the prevention and control of common problems. Craftsmanship Chapter 1. The characteristics of the diamond sand wear-resistant floor 1. Diamond sand floor Compared with ordinary concrete floors, diamond sand floors have better wear resistance, compressive strength and impact resistance, and have a longer service life. However, from the perspective of microstructure, the surface of the diamond sand floor is relatively rough, and the capillary structure of concrete has a low resistance to the penetration, pollution and corrosion of substances such as acids, alkalis and oils. 2. Corundum + cured floor The construction of adding curing agent to the diamond sand floor. When the diamond sand floor is applied with a curing agent, it better makes up for the above deficiencies. Moreover, as the curing agent penetrates and forms a film, it enhances the integrity of the original surface, significantly improving its surface strength and wear resistance. After long-term use, it is obviously superior to the ordinary diamond sand floor in terms of cracking, powdering, and dusting, and is also easier to clean. It has extremely strong wear resistance, pressure resistance and impact resistance The diamond sand floor itself has excellent wear resistance. After adding a curing agent, the strength and hardness of the floor are further enhanced, and its wear resistance, pressure resistance and impact resistance are also significantly improved, and the durability of the floor is greatly enhanced. 2) Prevent sanding and dusting The main advantage of the diamond sand reinforced floor is its ability to prevent sanding and dusting. After the application of the curing agent, the surface hardness (indicated by the diameter of the indentation) and wear resistance (indicated by the length of the grinding pit) can be effectively enhanced. The surface becomes denser and has better integrity, which can effectively prevent sanding and dusting. 3) Waterproof, oil-proof and anti-corrosion The surface of a common diamond sand floor has pores that are hard to see with the naked eye. Water, oil and other corrosive liquids can seep into the interior of the floor through these holes and gaps. The most notable feature of the curing agent is its excellent sealing property, just like coating the floor with a film to prevent erosion. 2. Acceptance Standards for diamond sand reinforced floor 1. The surface of the floor is firmly combined with the base layer, without any hollowing or sanding phenomena. 2. Surface layer quality: Uniform color, no obvious color difference, no scratches, no slag inclusions. The surface must not have cracks and hollowing is not allowed. 3. Gloss requirements: Achieve medium to high brightness, and the lamp should have a reflective effect when illuminated. 4. Joint: Uniform width, and the inside of the joint should be thoroughly cleaned. 5. The hardness of the floor should reach above 6.5 on the Mohs scale (tested by a hardness tester). 6. The trachoma rate shall not exceed 3 per square meter. 3. Construction Requirements 1. The strength of the concrete shall not be lower than C25. 2. The smallest possible water-cement ratio. A water-cement ratio that is too high can cause bleeding on the concrete surface and reduce the compressive strength of the concrete surface. Therefore, the water-cement ratio should be as small as possible, generally controlled below 0.5. 3. Commercial concrete should be used as much as possible. If on-site mixed concrete is used, its slump should be controlled at 1 to 3cm. The slump of commercial concrete is between 12 and 14cm. The diameter of the larger crushed stones shall not exceed 30mm. 4. When the concrete thickness is greater than 8cm, ordinary concrete should be used for pouring; when the concrete thickness is less than 8cm, fine aggregate concrete should be used for pouring. 5. Concrete should be leveled immediately after pouring, with a flatness of no more than 2mm within a 2-meter range. 6. Before the surface layer construction, the base concrete and vibration slurry should be sufficient (not less than 5mm). 7. The mud content of sand and gravel in concrete shall not exceed 2%. 8. After vibration grouting, the bleeding of the concrete should be uniform. If there are water pits, they must be removed and the surface leveled again; otherwise, the flatness of the diamond sand floor construction cannot be guaranteed. 4. Construction Techniques 1. Construction of diamond sand floor 1) The ground concrete is poured in sections and leveled immediately after pouring. When multiple locations are being poured simultaneously, pay attention to the construction sequence being carried out in one direction and consider the consistency of the mating surfaces. ② Concrete should be leveled with a long roller or a long straightedge after being pushed flat. Three to five hours after the concrete is poured, it should be observed that there is no bleeding on the surface and it has reached the initial setting state. 2) Use a mechanical trowel to tap the slurry in a round motion. For fine areas, use a wooden trowel to trim the edges. The main purpose is to smooth the concrete surface and reduce the floating slurry. Pay attention to troweling in the same direction as pouring. 3) Sprinkle the wear-resistant aggregate in two batches. In the first batch, evenly spread two-thirds of the wear-resistant material on the already troweled cement floor. 4) For the second time, evenly spread the remaining 1/3 of the wear-resistant material on the surface of the concrete, and use a mechanical trowel with a disc installed to work crisscross and cross at least twice. 5) Use a mechanical trowel (metal disc) to smooth it out multiple times back and forth. For the fine corners and edges, use a manual trowel in coordination with the construction. The time for the next process should be determined based on the temperature and humidity. 6) When the surface of the floor begins to harden, use a mechanical trowel with a metal blade to grind and smooth it, and repeat this operation 3 to 4 times. (Construction workers must wear soft flat shoes to avoid damaging the surface. The fine corners and edges should be polished by hand.) 7) Water curing should be carried out on the polished wear-resistant floor (mainly to prevent the evaporation of surface moisture and ensure the stable growth of the wear-resistant material's strength). The curing period is 7 days. 8) After the surface has cured for a certain period of time (5 to 6 hours after the completion of the wear-resistant material floor), use a mechanical trowel equipped with a metal blade for the final polishing and leveling. 9) Mold and compartment cutting (this can be done according to the actual situation on site and the owner's needs). Mold removal can be carried out the day after the completion of the diamond sand floor. During the operation, be careful not to damage the edge of the floor. The size of the compartments shall be determined by Party A on the third day after the completion of the diamond sand floor. 2. Application of penetrating liquid hardener (commonly known as curing agent) The original color of the diamond sand floor should be cured for more than 14 days, while the colored diamond sand floor usually needs to be cured for 28 days. Only after the color has matured can the penetrating liquid hardener be applied. The specific measures are as follows: Before construction, clean and remove debris, oil stains, paints, curing agents, etc. from the ground. If there are any pits or cracks, they should be repaired in advance with cement-based jointing mortar and maintained for 3 days. If no repair is needed, proceed with the construction directly. 2) Sprinkle water on the base layer until it is fully moistened. Do not sprinkle too much. 3) Use a 50-mesh resin grinding disc to grind the base layer, removing the floating slurry and stains on the base layer to make it free of roughness and gradually smooth. 4) After the 50-mesh grinding is completed, use a 150-mesh resin grinding disc for grinding. After grinding, use a high-power vacuum cleaner to suck up the mud and sewage on the surface of the base layer. 5) Sprinkle water on the surface of the base layer and grind it with a 300-mesh resin grinding disc (the ground should be ground evenly in a grid pattern, and the machine's pushing speed should be one step per second to grind off the remaining materials and fine scratches on the ground). After grinding, grind it with a 500-mesh grinding disc. Then, use a vacuum cleaner to suck up the wastewater and ventilate to dry the base layer. 6) After the base layer is dry, if the surface turns slightly white, apply the concrete sealant and hardener. Sprinkle the material evenly and spread it evenly with a mop. Keep the base layer surface moist for 30 minutes. If there is rapid penetration in some areas and it has dried, sprinkle the material again and use a mop to evenly moisten the base layer. 7) After 30 minutes, the surface of the concrete sealant and hardener begins to thicken. Water should be sprinkled on its surface and pushed back and forth with a long-bristled brush or floor scrubber to dilute the excess hardener and better penetrate into the base layer. After one hour, the excess material and water should be sucked dry with a vacuum cleaner to ensure that the base layer is dry for more than 12 hours. 8) After 12 hours, sprinkle water on the base surface of the completed construction material, and grind it with a 500-mesh resin grinding disc to remove the excess material. Then, grind it with a 1000-mesh grinding process. After grinding, use a vacuum cleaner to suck up the wastewater. 9) After 12 hours, the base layer has basically dried. Then, it is ground and polished with a 2000-mesh resin grinding disc to gradually give its surface a lustrous appearance. 10) For each mesh size, the grinding discs should be cross-ground 3 to 5 times in both the longitudinal and transverse directions. 11) Special treatment ① Corner and edge treatment: Large machinery can only be used for large-scale grinding. For corner and edge positions, a portable Angle grinder should be used for grinding and polishing, following the same method as for large-scale construction. When the base layer has poor strength and severe sanding, it is necessary to reinforce the base layer first, and then proceed with the normal construction process. First, use a 300-mesh resin grinding disc to remove the floating slurry on the surface of the base layer. Then, evenly sprinkle the concrete sealant and hardener to ensure it fully wets and penetrates into the base layer. After 12 hours, when the concrete sealant and hardener has cured and the strength of the base layer has improved, follow the normal process: 50-mesh grinding (water grinding) → 150-mesh grinding (water grinding) → 300-mesh grinding (water grinding) → construction materials → 12-hour drying and curing → 500-mesh grinding (water grinding) → 1000-mesh grinding (water grinding) → 2000-mesh grinding (dry grinding). The aesthetic effect of the floor cannot be achieved without meticulous control during the construction process. Besides strictly adhering to the corresponding techniques and methods, the prevention of common quality problems also requires attention. If the construction is not done properly, many problems will occur during later use. Now let's talk about the common quality problems of the diamond sand wear-resistant floor and how to prevent them. Prevention of Common Diseases 1. Color difference There are mainly three reasons for the color difference of corundum: 1) Material selection issues; 2) The materials were not spread in several portions, the amount of materials used was insufficient, and the thickness was uneven. 3) Maintenance issues: The use of covering with plastic film for maintenance led to uneven evaporation of ground moisture. The area where the film comes into contact with the floor is whitish, while the area where it does not touch the floor is normal in color. Preventive measures Choose a manufacturer with stable and reliable product quality and a good reputation. 2) The spreading of materials should be carried out strictly in accordance with the requirements of the briefing in several portions, with a usage of no less than 5kg/m². 3) Plastic film curing is strictly prohibited. During summer construction, water spraying curing can be adopted in several batches (with an interval of 2 to 3 hours). 2. The ground flatness is out of tolerance The allowable deviation of ground flatness is ≤2.5mm/2m in both longitudinal and transverse directions. The reasons for the deviation during construction are: 1) The template setup is out of tolerance; 2) The concrete part was not leveled in accordance with the standard. 3) The wear-resistant material is not evenly spread. Preventive measures 1) Strictly calibrate the elevation lines. Set up steel rods every 2 meters or so. The elevation of the steel rods should be the same as that on the longitudinal seam formwork. Check with a level. 2) The joints should be roughened and leveled in advance. When pouring new concrete, the levelness should be consistent with that of the already poured ground. Any low-lying areas should be replenished and filled in a timely manner. 3) Wear-resistant aggregates should be spread in two portions. The first dosage should be two-thirds of the total dosage. Ensure that the mixture falls evenly. Do not throw it forcefully to avoid the separation of aggregates and cement. After the wear-resistant material has absorbed a certain amount of moisture, it is ground and dispersed with a grinding machine and then combined with the base concrete slurry. For the second spreading, apply the remaining one-third in a direction perpendicular to that of the first spreading. When spreading, first use a straightedge or a straight scraper to measure the levelness, and adjust the uneven areas of the first spreading. After spreading, immediately smooth and polish it, and repeat the grinding machine operation at least twice. When the grinding machine is in operation, it should be carried out alternately in the longitudinal and transverse directions, evenly and orderly, to prevent material accumulation. The third time mainly involves repair treatment. For low-lying areas, materials are replenished and leveled. For corners and edges that cannot be covered by the grinding machine, manual flattening and smoothing are adopted. 3. Ground cracks There are the following situations regarding ground cracks: If the initial setting time of concrete is not well controlled and the diamond sand wear-resistant aggregate is scattered when the moisture content of the concrete is relatively low, it is easy to cause cracks after the construction is completed. 2) Improper construction methods, insufficient thickness of the wear-resistant layer (corundum layer), rapid water loss (such as excessive construction environment atmosphere, etc.), resulting in volume shrinkage and linear shrinkage, causing cracks or hollowing. 3) Improper maintenance: After the completion of construction, the ground was not maintained within the prescribed time or was not adequately watered for maintenance. When the concrete temperature is relatively high, pouring cold water for curing can also cause cracks. Note: When using only the diamond sand floor, it is recommended to use a maintenance agent (oily and film-forming effect) to maintain the floor. If the corundum is reinforced (or epoxy), water curing can be directly adopted. 4) The contraction joint was cut late, and cracks appeared due to thermal expansion and contraction. Under normal circumstances, it is advisable to cut the expansion joints 24 to 48 hours after the completion of the construction of the corundum floor. If it is too late, as the hardness of the floor gradually increases, the floor is prone to "cracking" and developing cracks during the cutting process. 5) If the spacing of the division joints is too large, cracks may also occur. Preventive measures 1) Strictly control the time of the first sprinkling of materials; 2) The concrete layer and the wear-resistant layer (corundum) are constructed simultaneously. 3) The curing time shall be no less than 14 days; 4) Reasonably control the cutting time; The spacing of the division joints should generally not exceed 6m*6m. 4. The ground is sandy, peeling or pitted Cause of formation 1) The roughening and polishing processes are rough. 2) Inadequate maintenance and insufficient maintenance time; 3) The spreading time of wear-resistant aggregates is not well controlled. Preventive measures 1) Use a grinding machine to thoroughly smooth, compact and roughen the ground for no less than three times, and use a floor trowel to thoroughly smooth and level the ground for no less than three times. 2) The curing time shall be no less than 14 days; 3) Strictly control the spreading time of wear-resistant materials. The timing of spreading wear-resistant materials varies as needed, depending on factors such as climate, temperature, and concrete mix ratio. Spreading too early will cause the wear-resistant material to sink into the concrete and lose its effect. If it is spread too late, the concrete will gradually lose its adhesive force due to solidification, preventing the wear-resistant material from fully bonding with it. The most convenient way to determine the time for spreading wear-resistant materials is to let your feet sink about 5mm when stepping on the ground, and then you can start the first spreading work. The moisture at the edges of walls, columns, doors and formwork disappears more quickly. It is advisable to prioritize the application of water to prevent the effect from being reduced due to water loss. 5. Remedial Measures 1. Local damage: Clean the damaged area thoroughly, soak it in water to moisten it, then repair it with a putty made of styrene-butadiene latex mixed with water and a hardener material that has screened out the aggregates. Finally, apply the styrene-butadiene latex mixed with water emulsion. 2. Large-scale damage: According to actual needs, lines can be drawn and sawn on the damaged area, the surface layer and part of the base layer can be chiseled off, then the area can be cleaned and moistened, the plain cement slurry can be swept, concrete can be poured, and finally the surface layer of the diamond sand hardener can be applied. 3. Floor peeling: The surface of the wear-resistant diamond sand floor curls and peels. Remedial measures: Cut and chisel off the peeling area (chiseling it into a pitted surface), spray water on the pitted area to moisten it, then apply repair mortar of the same grade as the concrete and press it down to level the ground. Finally, apply a curing agent. 4. Remedial measures for cracks in diamond sand floor: 1) Cracks in areas with requirements for anti-seepage, impact resistance and wear resistance on the surface should undergo surface treatment. 2) For cracks that can affect the integrity, strength, impermeability and steel bar corrosion of the structure, grouting treatment should be carried out. 3) For cracks that endanger the safe operation of buildings, in addition to grouting treatment, other reinforcement measures should also be taken when necessary. 4) Cracks that are sensitive to temperature should be treated when the crack opening is relatively large in the later stage of the low-temperature season. 5) Flexible materials must be used to treat active cracks. Note: The parameters provided in this document are for reference only and are not mandatory. Due to differences in technical characteristics between different brands and models of laser levelers, please consult the manufacturer for a suitable solution before actual operation. This reference document assumes no responsibility for any issues arising from failure to follow the manufacturer's instructions.

In the field of construction engineering, leakage has always been a core threat to structural safety and functional experience – moisture in basements leads to moldy decoration, roof seepage erodes steel bars, and wall leakage affects living comfort, and it will also accelerate the carbonation of concrete and the aging of the structure. Traditional waterproofing techniques (membranes, coatings) rely on external additional layers, which are prone to failure due to material aging, construction hollowing, and temperature difference deformation. Although ordinary self-waterproofing structures enhance their impermeability by optimizing the density of concrete, they are difficult to deal with micro-cracks caused by temperature stress and load fluctuations in the later stage. Self-healing structural self-waterproofing technology, with its innovative mechanism of "actively repairing micro-cracks", has achieved a leap from "passive anti-seepage" to "active self-healing", and has become a core waterproofing solution for high-end buildings and special projects. This article, based on the technical practices of the three major brands, Pengneichuan (Penetron), Sika, and liwei, systematically analyzes the technical key points, brand differentiation solutions, and engineering application norms of self-healing structure self-waterproofing. I. Technical Definition and Core Logic of Self-healing Structure Self-waterproofing 1. Concept: Self-healing structural self-waterproofing is based on the "material improvement – construction control – structure optimization" of ordinary structural self-waterproofing. By adding self-healing functional components (such as active crystallization agents, capsule repair agents, microbial agents, etc.), after the concrete generates micro-cracks with a width of ≤0.3mm, it can be triggered by moisture, air or chemical conditions. A technical system for independently completing crack filling and restoring impermeability performance. 2. Core logic: "Hazard Prediction – Proactive Response – Performance Reset" (1) Hidden danger prediction: During the service of buildings, due to temperature changes (thermal expansion and contraction), load fluctuations (dynamic load impact), and dry-wet cycles, 0.1-0.3mm micro-cracks are bound to occur (the crack resistance of ordinary concrete is limited, and such cracks are hard to avoid), and cracks are the main channels for water seepage. (2) Active response: The "self-healing components" pre-installed inside the concrete (such as Pengnei Chuan's active crystalline particles and Sika's capsule repair agent) are activated when cracks occur – either reacting with water to form a gel, or breaking to release the repair agent, or being metabolized by microorganisms to produce crystals; (3) Performance reset: Self-healing products fill the cracks and re-form a dense impermeable barrier, restoring the original impermeability of the concrete. This technology is particularly suitable for scenarios with extremely high requirements for waterproofing reliability and durability, such as subway tunnels, nuclear power plants, water conservancy projects, and basements of super high-rise buildings. Ⅱ. Key technical Links of Structural Self-waterproofing The implementation of self-healing structure self-waterproofing should revolve around "self-healing material selection – construction adaptation – performance verification", and the core technical links should comply with the "Technical Code for Self-Healing of Concrete Structures" (CECS 378-2021) and relevant national standards: 1. Material selection: Core component of self-healing waterproof concrete The performance key of self-healing waterproof concrete lies in the "self-healing functional components". Currently, the mainstream technical routes are divided into three categories, and the appropriate solution should be selected according to the engineering scenario: Self-healing technology route Internal admixture self-healing agent Microbial self-healing Fiber-reinforced self-healing In addition, the base concrete should meet the following requirements: strength grade ≥C35, impermeability grade ≥P8, and the admixtures should be Grade I fly ash (with a content of 15%-20%) or mineral powder (with a content of 25%-30%) to enhance the density of the concrete and the compatibility with self-healing components. 2. Construction control: Specialized requirements adapted to self-healing characteristics The construction of self-healing concrete should, on the basis of the self-waterproofing of ordinary structures, strengthen the "uniformity of self-healing components" and "crack induction control", with key control points: (1) Mixing and pouring: For capsule-type self-healing agents, the "post-mixing method" (adding them in the last 30 seconds of concrete mixing) should be adopted to prevent capsule rupture. Microbial agents need to be added simultaneously with the aggregates, and the stirring time should be extended to 120-150 seconds to ensure the uniform distribution of the agents. The thickness of the layered pouring should be no more than 400mm, and the spacing of the vibration rods should be no more than 350mm to prevent the aggregation or damage of self-healing components. (2) Curing and crack induction: Within 24 hours after pouring, adopt "water storage + film covering" curing (humidity ≥90%, temperature ≥15℃), and extend the curing period to 21 days – sufficient moisture can activate self-healing components (such as microbial metabolism, expansive agent reaction); For large-volume concrete, "induction joints" (with a spacing of 8-10m and a depth of 50-80mm) should be reserved on the surface to guide the formation of cracks at the preset positions, facilitating the concentrated repair of self-healing components. (3) Construction joint treatment: In addition to the conventional waterstop steel plate, a "self-healing interface agent" (such as microbial agent slurry, with a application rate of 0.3kg/㎡) should be applied to the interface of the construction joint to enhance the self-healing ability of the new and old concrete bonding surface and prevent interface leakage. 3. Construction Synergy: Auxiliary design for enhancing self-healing effects (1) Moisture guidance structure: Set up "micro-seepage water channels" (10-15mm in width and 0.5% in slope) on the basement floor and roof slabs. When micro-cracks occur, guide the moisture to contact the self-healing components, accelerating the repair reaction. (2) Monitoring and supplementary repair nodes: Pre-embed "crack monitoring sensors" (with an accuracy of 0.01mm) at key locations such as tunnels and water pools to monitor the crack width in real time. If the crack exceeds the self-healing range (> 0.3mm), self-healing slurry (such as microbial agent slurry) can be injected through the pre-embedded grouting pipe to achieve artificial auxiliary repair. (3) Node reinforcement: The part where the pipe passes through the wall plate adopts "self-healing waterproof sleeve" (the inner wall of the sleeve is coated with permeable crystalline paint, and the gap is filled with expansive self-healing sealant), providing dual protection for the impermeability of the node. Ⅲ. Performance Comparison between Self-healing Structural Self-waterproofing and structural Self-waterproofing as well as Traditional waterproofing From the three dimensions of anti-seepage, repair and lifespan, the self-waterproofing advantages of the structure are significant. The specific comparison is as follows: Comparison dimension Traditional waterproofing (membrane/coating Ordinary structure self-waterproofing Self-healing structure is self-waterproof Crack treatment capacity The crack cannot be repaired and leakage is prone to occur at the crack Relying on the inherent density of concrete, micro-cracks are prone to develop into leakage channels Actively repair micro-cracks of ≤0.3mm to prevent leakage from spreading Service life 5 to 10 years (material aging) 30 to 40 years (cumulative failure due to micro-cracks) Have the same lifespan as the building (≥50 years, with continuous self-healing function) Environmental adaptability It is prone to aging at high or low temperatures and has poor resistance to acids and alkalis It has good weather resistance, but its resistance to chemical erosion is limited Acid and alkali resistant (microbial type), high and low temperature resistant (-30℃ to 80℃) Later maintenance cost The maintenance cost is approximately 60% of the initial cost every 10 years Grouting repair is required every 20 years, with a cost of approximately 30% of the initial No regular maintenance is required. Only in extreme cases is auxiliary repair needed Applicable scenarios Roofs and bathrooms of civil buildings General basements and factory buildings Subways, nuclear power plants, water conservancy hubs, super high-rise buildings Ⅳ. Common Misunderstandings about Structural Self-Waterproofing Misconception 1: Self-healing concrete can repair all cracks At present, the mainstream technology can only repair micro-cracks with a width of no more than 0.3mm. If the crack width is greater than 0.3mm (such as structural cracks caused by loads), epoxy resin grouting and sealing should be used first, and then the micro-branch cracks should be repaired by self-healing components. The self-healing function cannot be relied on completely. Misconception 2: Self-healing concrete does not require acceptance testing It is necessary to add a "Self-healing performance special Test" : ① Artificial jointing test (prefabricate 0.2-0.3mm cracks on concrete test blocks, and test the permeability after 28 days of water storage, which should be ≤0.01L/m² · h); ② On-site core sampling inspection (drill a core sample of Φ100mm and observe the crack healing condition. The healing rate should be ≥80%). Misconception 3: Self-healing types are too costly and not suitable for civil buildings Although the initial material cost is 15% to 20% higher than that of ordinary self-waterproofing structures, the total life cycle cost is lower. Calculated based on a 70-year building lifespan, ordinary self-waterproofing structures require 2 to 3 repairs, and the total cost is approximately 1.8 times that of self-healing types. At present, in civil buildings, some high-end residential basements and roofs have adopted a composite solution of "microbial self-healing + penetrating crystallization", and its cost performance is gradually improving. Ⅴ. Key Points for Engineering Application and Acceptance of Structural Self-Waterproofing 1. Application cases and key points of new construction projects (1) Metro tunnel: Use "capsule-type self-healing agent + fiber reinforced" waterproof concrete (C40/P10), with a self-healing agent dosage of 1.0kg/m³ and a fiber dosage of 1.2kg/m³. During construction, the reserved spacing of the induction joints is 8 meters, and the curing period is 21 days. One year after the opening to traffic, the micro-crack healing rate of the tunnel lining reached 92%, and there was no leakage. (2) Water conservancy water pool: "Microbial self-healing concrete" (C35/P12) is adopted, with a microbial agent concentration of 10⁹ CFU/mL and a nutrient carrier dosage of 2.0kg/m³. Through the monitoring of pre-embedded sensors, the 0.2mm crack was completely healed within six months, and the permeability coefficient dropped below 1×10⁻¹¹ m/s. 2. Application in the renovation of existing buildings When applying self-healing structural self-waterproofing to old buildings, it is necessary to first carry out the process through three steps: "crack detection – interface treatment – self-healing enhancement". (1) Crack detection: Use an ultrasonic detector to scan the walls and floor slabs, mark the location and width of the cracks. For cracks larger than 0.3mm, grouting and sealing are carried out first. (2) Interface treatment: Chisel off the original concrete surface layer (with a depth of 30-50mm), and apply a "self-healing interface agent" (such as a mixture of silica fume and microbial agent slurry). (3) Construction of self-healing reinforcing layer: Pour 50-80mm thick self-healing fine aggregate concrete (C35/P8, mixed with 0.8kg/m³ expansive self-healing agent), and conduct a water-tightness test after 14 days of curing to ensure there is no leakage. 3. Special acceptance criteria The following acceptance items should be added in accordance with the "Technical Code for Self-Healing of Concrete Structures" (CECS 378-2021) : (1) Detection of self-healing component dosage: The sampling and weighing method is adopted to ensure that the dosage of self-healing agent and bacterial agent meets the design requirements (deviation ≤±5%). (2) On-site self-healing performance testing: Pre-fabricate 0.2mm cracks on the structural surface. Observe no leakage after 24 hours of water storage. After 28 days, test the crack healing rate to be ≥80%. (3) Long-term monitoring data: The embedded sensors need to provide a report on the change in crack width within six months to ensure that no new cracks occur and the old ones continue to heal. The self-healing structural self-waterproofing technology, through an innovative mechanism of "actively repairing micro-cracks", addresses the pain points of traditional waterproofing, such as "easy failure", and ordinary structural self-waterproofing, such as "difficult crack resistance". It is particularly suitable for engineering scenarios with extremely high requirements for waterproofing reliability and durability. With the decline in material costs and the maturation of technology, it will gradually be popularized in civil buildings in the future. Note: The parameters provided in this document are for reference only and are not mandatory. Due to differences in technical characteristics between different brands and models of laser levelers, please consult the manufacturer for a suitable solution before actual operation. This reference document assumes no responsibility for any issues arising from failure to follow the manufacturer's instructions.

When you leap with all your might on the sports field and your running shoes draw graceful arcs on the track, the ground beneath your feet is your most loyal "invisible guardian". The sports ground is not merely a "flooring material", but a precise system that integrates materials science, ergonomics and sports mechanics. NO.01 The concept of sports flooring Sports flooring refers to the ground material layer specially designed and constructed for various sports competitions and fitness activities. It needs to meet the requirements of elasticity, anti-slip, wear resistance, shock absorption and environmental protection for sports, and adapt to the technical requirements of different sports. NO.02 Classification of sports flooring Ⅰ. Plastic Track Floor: 1. Concept: The plastic track floor is an elastic ground material made of synthetic resins such as polyurethane (PU) and polyvinyl chloride (PVC) as the main binders, mixed with rubber particles and other raw materials. It is also known as an all-weather sports floor and is commonly seen in basketball courts, badminton courts and other venues. Due to its good elasticity, anti-slip and wear-resistant properties, it has become the mainstream choice for modern sports venues. 2. Advantages: Excellent elasticity, good anti-slip performance, high rebound rate, wear-resistant and shock-resistant, customizable according to the needs of different sports venues, and highly practical. 3. Disadvantages: Large initial investment, may release a slight odor at high temperatures, improper construction is prone to problems such as bulging and delamination, and the difficulty of later repair is relatively high. 4. Applicable venues: ball game venues, various types of track and field tracks, comprehensive sports venues in schools and stadiums, simple sports venues in communities and parks. Ⅱ. Acrylic Sports Flooring Concept: Acrylic flooring is a new type of environmentally friendly flooring material composed of acrylic resin as the core component, combined with pigments, fillers and additives. 2. Advantages: Green, environmentally friendly and pollution-free, with excellent weather resistance and anti-aging ability, stable structure and not easy to fall off, long-term stable and reliable material performance, and simple construction process, short cycle and quick effect, suitable for a wide range of scenarios 3. Disadvantages: It has high requirements for the flatness of the base layer. An uneven base layer can easily lead to cracking and peeling of the coating. It has a relatively weak ability to resist the impact of heavy objects and is prone to damage when subjected to long-term heavy pressure or sharp object impacts. The stain resistance is average. Stubborn stains need to be cleaned up in time; otherwise, it is easy to leave marks. In low-temperature environments, its toughness decreases. Long-term use in extremely cold regions may lead to brittle cracking, and color differences are likely to remain after repair. 4. Applicable venues: Indoor and outdoor basketball courts, tennis courts, badminton courts and other professional sports venues as well as sports venues for leisure and entertainment. Ⅲ. Artificial Turf 1. Concept: Artificial turf can be classified into two major categories based on the production process: injection-molded artificial turf and woven artificial turf. (1) Injection-molded artificial turf: It adopts an integrated injection molding process, where plastic particles are extruded into shape in a dedicated mold at one time. Subsequently, professional bending techniques are used to make the grass leaves present a naturally curved shape. The arrangement of its grass leaves follows the rule of equal spacing and equal quantity, maintaining a completely uniform height, with excellent flatness and regularity. (2) Woven artificial turf: With synthetic fibers that imitate the shape of natural grass leaves as the core material, the fibers are precisely implanted into the woven base fabric through specialized equipment, and then a fixed coating is evenly applied to the back to enhance structural stability. It has a high degree of simulation, excellent toughness and is applicable in a wide range of scenarios. 2. Advantages and disadvantages: (1) The injection molding type adopts an integrated injection molding process, featuring regular grass leaves, low cost, wear resistance and easy maintenance. Its safety is suitable for children's scenarios, but its simulation degree and elasticity are average. (2) The woven type involves embedding synthetic fibers into the base fabric and applying a fixed coating. It features high simulation, comfortable foot feel, and excellent elasticity, making it suitable for professional venues. However, it has a relatively high cost and requires regular maintenance 3. Applicable scenarios (1) Injection-molded artificial turf can be used in multiple aspects such as activity areas in kindergartens, auxiliary areas of sports fields, balcony decoration, urban greening projects, and the laying of sand and gold fields. (2) Woven artificial turf can be widely applied in professional sports fields, leisure activity areas, golf courses, courtyard floor laying and urban greening projects, etc. Ⅳ. Silicon PU Court Floor 1. Concept: The silicon PU court floor is composed of elastic base material for the court, wear-resistant surface material, topcoat, marking lines and other parts 2. Advantages: It features outstanding wear resistance, weather resistance and anti-fouling properties. Moreover, the surface layer of the court can be adjusted to various colors as needed to beautify the environment and bring visual enjoyment. 3. Disadvantages: Higher initial investment cost, strict environmental requirements for construction, slight yellowing may occur when exposed to strong light for a long time, affecting the consistency of appearance, weak resistance to scratches from sharp objects, easy to leave marks when scratched by hard objects, and there may be color differences after repair. 4. Applicable scenarios: It is suitable for professional sports venues such as indoor and outdoor basketball courts, tennis courts, and badminton courts. It is also compatible with activity areas in kindergartens, school playgrounds, leisure and fitness areas, and children's play areas. Ⅴ. Suspended Modular Floor 1. Concept: Suspended modular floor, also known as modular sports floor, is made of high-strength polypropylene environmentally friendly material at its core. It does not require professional bonding and can be directly laid on flat base surfaces such as cement and asphalt. Through the unique locking structure of the floor itself, it can be quickly assembled and fixed. 2. Advantages: It features environmental friendliness, durability, convenience, portability, cold and heat resistance, anti-aging, comfort, safety and health, as well as excellent sports performance 3. Disadvantages: It relies on the flatness of the base layer, the lock buckle is prone to loosening due to high-intensity use or temperature changes, the texture is relatively hard, the movement buffering performance is average, the anti-slip performance will decline with the passage of time, and it is prone to cracking at low temperatures. 4. Applicable scenarios: It can be used to lay ideal high-performance basketball courts, tennis courts, roller skating courts, table tennis courts, and multi-functional courts such as volleyball and badminton courts. It can also be used in various domestic sports venues and playgrounds and sports fields in kindergartens and primary schools. The texture, safety and comfort of sports fields are all hidden in every detail of the floor. Whether it is the wear resistance and elasticity required for professional events or the environmental protection and anti-slip features valued in school playgrounds and community leisure areas, high-quality floors silently protect every run, jump and laugh, laying a solid foundation of peace of mind for sports moments in different scenarios. Note: The parameters provided in this document are for reference only and are not mandatory. Due to differences in technical characteristics between different brands and models of laser levelers, please consult the manufacturer for a suitable solution before actual operation. This reference document assumes no responsibility for any issues arising from failure to follow the manufacturer's instructions.