How to deal with the possible faults and problems during the leveling process of concrete laser leveling machine?

 

  At the moment when the construction field is constantly innovating, the pursuit of flatness, strength and construction efficiency in large-area floor construction has reached a new height. Traditional construction methods are difficult to accurately control flatness when dealing with large-scale ground operations, and the construction period is long. The use of concrete laser leveling machine Beton – Laser – Nivelliermaschine to implement one-time forming construction has become an effective solution to break through these bottlenecks and provide strong guarantees for creating high-quality ultra-flat wear-resistant floors. Excellent precision: With the help of advanced laser systems, Macchina livellatrice laser per calcestruzzo has extremely high control accuracy for ground elevation, and can control flatness deviation within a very small range, far exceeding traditional construction methods, and meeting the stringent requirements of high-standard ultra-flat floors. Efficient operation: The equipment has a leading degree of automation, and a large area of ​​ground leveling can be completed in a single operation. Compared with traditional manual leveling, the construction period is greatly shortened and the construction efficiency is greatly improved. Material optimization: With precise elevation control, it can effectively avoid the situation of too much or too little concrete laying, reduce material waste and construction costs. Performance enhancement: Uniform vibration during the leveling process makes the internal structure of the concrete more compact and uniform, significantly enhances the strength and wear resistance of the ground, and extends the service life of the ground. This method is widely used in various large-area places with high requirements for ground flatness and wear resistance, such as industrial plants that need to withstand the operation of heavy equipment; logistics warehouses, where frequent cargo handling causes great damage to the ground; large shopping malls, where there is a large flow of people and the ground needs to be beautiful; parking lots, where vehicles frequently enter and exit and test the durability of the ground, etc. The core of Extendedoras de hormigón lies in the collaborative work of high-precision laser transmitters and receivers. The laser transmitter emits a stable horizontal laser beam, just like building a precise reference plane in the air. The laser receiver is installed on the leveling machine frame to capture the laser signal in real time and quickly transmit it to the control system. The control system automatically and accurately adjusts the height of the screed blade according to the received signal to ensure accurate leveling of the concrete surface during the process. At the same time, the vibrating device equipped with the screed works synchronously to fully vibrate the concrete, ensure its density, and lay the foundation for high-quality ground. Base treatment → measurement and layout → installation of formwork → concrete pouring → laser leveling machine leveling → surface treatment (smoothing, spreading wear-resistant materials, etc.) → maintenance Base treatment Thoroughly remove debris, dust, oil and other pollutants on the surface of the base to ensure that the surface of the base is clean and flat, providing a good foundation for subsequent construction. Use compaction machinery to compact the base. For weak foundations, effective measures such as replacement and reinforcement piles are required to improve the bearing capacity of the base and prevent later ground settlement. Measurement and layout Use precision measuring instruments such as total stations to accurately measure and lay out the elevation control lines and construction boundaries of the floor according to the requirements of the design drawings. Set firm control points at a certain distance (usually 3-5 meters) on the base. These control points serve as key references for the initial positioning and calibration of the laser leveling machine to ensure the accuracy of the equipment's running trajectory and elevation control. Install the formwork Install the formwork strictly according to the measured layout position. The formwork should be made of materials with high strength and good rigidity, such as high-quality steel formwork or reinforced wooden formwork. Use a level to accurately adjust the elevation of the top surface of the formwork so that it is completely consistent with the design elevation. The joints of the formwork should be tight, and sealing strips or tapes can be used to seal to prevent leakage during concrete pouring and affect the quality of the ground. Preferably use commercial concrete, and its mix ratio needs to be professionally optimized according to factors such as engineering design strength, durability, and construction environment to ensure that the concrete performance meets the construction requirements. Concrete is efficiently transported to the construction area through equipment such as concrete pump trucks or mixer trucks. Pour in layers and sections from one end to the other. The pouring thickness should be 2-3 cm higher than the design elevation, and space for leveling should be reserved. During the pouring process, use an inserted vibrator or a flat vibrator to vibrate the concrete in time. The vibration points should be evenly distributed to avoid leakage or over-vibration and ensure the density of the concrete. Laser leveling machine leveling After the concrete pouring is completed, the laser leveling machine should be driven into the construction area as soon as possible to avoid the initial setting of the concrete affecting the leveling effect. Start the laser transmitter and laser leveling machine in turn, calibrate and debug the equipment comprehensively, and check whether the laser signal reception, scraper lifting control, and vibration device operation are normal. The operator sets a reasonable leveling machine route and speed according to the shape and area of ​​the construction site. The general speed is controlled at 1-3 meters per minute. During the leveling machine's movement, pay close attention to the equipment's operating status and the concrete surface. If local unevenness, depressions or convexities are found, stop the machine immediately and use manual filling or shoveling to repair. Surface treatment For ordinary floors, use a trowel machine for mechanical troweling after the initial setting of the concrete and before the final setting. The trowel machine operates in a horizontal and vertical cross-pattern, and generally needs to be troweled 3-5 times until the ground surface is flat, smooth, and free of smear marks. For wear-resistant floors, when the concrete is initially set, the wear-resistant materials (such as metal aggregates and non-metallic aggregate wear-resistant materials) selected according to the design requirements will be evenly spread on the concrete surface, and the spreading amount will be determined according to the material description and design requirements. After spreading, use a trowel to smooth the surface so that the wear-resistant materials and concrete are fully integrated to form a solid and wear-resistant floor surface. Maintenance After the ground construction is completed, maintenance work should be carried out immediately. Sprinkling maintenance can be used. The number of sprinkling times per day is determined according to the temperature and humidity, generally not less than 3-5 times, to keep the ground moist; plastic film can also be covered to prevent water evaporation and maintain the internal humidity of the concrete; curing agent can also be sprayed to form a protective film on the ground to achieve the maintenance effect. The curing time is usually not less than 7-14 days, and the specific duration is determined according to the concrete strength growth and relevant specifications. During the maintenance period, it is strictly forbidden for people and vehicles to walk or roll on the ground to prevent damage to the ground strength growth process and ensure that the final strength of the ground meets the design requirements. Concrete: must strictly meet the design strength grade requirements, have good workability, fluidity and durability, and ensure easy pouring and vibration during construction. Wear-resistant materials: accurately select wear-resistant materials according to the actual needs of the project and design standards. Metal aggregate wear-resistant materials have the characteristics of high hardness and high strength; non-metal aggregate wear-resistant materials have excellent performance in impact resistance and anti-static, and can be selected as needed. Formwork materials: steel formwork has the advantages of high strength and high turnover; wooden formwork has certain advantages in shape adaptability and splicing flexibility. Appropriate formwork materials can be selected according to construction conditions and cost considerations, but their strength and rigidity must meet construction requirements. Extendedoras de hormigón: According to the size of the construction site, the complexity of the shape and the ground design requirements, reasonably select equipment models with power, leveling width and accuracy. Laser transmitter and receiver: Closely matched with laser leveling machine, laser transmitter emits stable and accurate laser beam, receiver accurately captures signal, the two work together to ensure high precision of elevation control, and their performance directly affects the quality of ground leveling. Concrete delivery equipment: Concrete pump truck has strong mobility and is suitable for concrete delivery in different site conditions; mixer truck can ensure the uniformity and working performance of concrete during transportation, and can be reasonably used according to the construction site conditions. Trowel machine: Divided into hand-held type and driving type, selected according to the ground area and construction efficiency requirements. Its high-speed rotating trowel compacts and smoothes the ground to make the ground flat and smooth. Measuring instruments: Total station is used for large-area high-precision measurement and layout; level can accurately measure elevation; theodolite assists in determining angles and verticality. These measuring instruments jointly provide accurate data support for positioning and elevation control during construction. Quality management system construction: Set up a professional quality management team to clarify the specific responsibilities of each member in the stages of construction preparation, construction process and quality acceptance. Formulate a detailed quality management system and set clear and quantifiable quality goals, such as controlling the ground flatness deviation within ±2 mm. Raw material quality control: Each batch of raw materials such as concrete and wear-resistant materials entering the site shall be inspected and tested strictly in accordance with relevant standards. Concrete needs to be tested for slump, compressive strength and other indicators; wear-resistant materials need to be tested for their wear resistance, hardness and other properties to ensure that the quality of raw materials fully meets the design and specification requirements and ensure the quality of the project from the source. Construction process quality supervision: Arrange professional quality management personnel to supervise the entire construction process and strictly follow the established construction process and operation points. Focus on monitoring whether the laser operation is standardized, including equipment calibration, travel speed and route control; whether the concrete pouring and vibration meet the requirements, such as pouring sequence, vibration time and depth, etc.; the timing of polishing in the surface treatment process, the uniformity of wear-resistant material spreading, etc., and timely rectification when problems are found. Quality acceptance: After the construction is completed, the ground is comprehensively inspected in accordance with the current relevant national specifications and standards. Use professional measuring tools to detect the flatness and elevation deviation of the ground; use equipment such as rebound testers to detect the ground strength; and use wear resistance testers to test the wear resistance of wear-resistant floors. Only after all indicators meet the requirements after testing can the project quality be determined to be qualified. Building a safety management system: Develop a complete safety management system covering all aspects such as construction site safety protection, equipment operation specifications, and personnel safety training. Clarify the safety responsibilities of personnel in various positions, and implement safety responsibilities at all levels from project managers to front-line construction personnel. Safety education and training: Regularly organize construction personnel to participate in safety education and training, including safety regulations, safety operating procedures, accident case analysis, etc. New employees must undergo three-level safety education and training and pass the assessment before they can take up their posts. Special types of work (such as electricians, welders, machine operators, etc.) must be certified to work, and continuously improve the safety awareness and operating skills of construction personnel. Safety protection at the construction site: Set up obvious safety warning signs at the entrance of the construction site and dangerous areas (such as deep foundation pits, high-altitude working areas, etc.). Set up protective railings and safety nets for high-altitude working surfaces; equip construction workers with qualified personal protective equipment such as safety helmets, safety belts, safety shoes, and supervise their correct wearing and use. Equipment safety management: Establish a regular inspection and maintenance system for construction equipment such as laser levelers and concrete conveying equipment, conduct equipment appearance inspections and performance tests before and after each use, and conduct regular comprehensive maintenance and repairs. During the operation of the equipment, operators must strictly abide by the operating procedures, and illegal operations are strictly prohibited to prevent safety accidents caused by equipment failures or improper operations. Construction dust control: Harden the main roads in the construction site, and arrange special personnel to sprinkle water to reduce dust regularly. Sand, stone and other materials that are prone to dust are stored in closed silos, or covered with dustproof nets to reduce dust pollution. Construction noise control: Plan construction time reasonably to avoid high-noise operations during residents' rest time (such as 22:00 to 6:00 the next day). Take noise reduction measures for high-noise equipment such as concrete pumps and vibrators, such as installing silencers and setting up soundproof covers, to reduce the impact of construction noise on the surrounding environment. Waste treatment: Set up classified trash cans and waste storage sites at the construction site to classify and collect construction waste and domestic waste generated during the construction process. Recyclable waste (such as scrap steel, waste wood, etc.) is recycled and reused; non-recyclable waste is transported to designated locations for proper disposal in accordance with the requirements of local environmental protection departments to prevent environmental pollution.   Economic benefits: The one-time forming construction method of the laser leveling machine has greatly improved construction efficiency, shortened the construction period, and correspondingly reduced labor costs and equipment rental costs. Accurate leveling effectively reduces concrete waste and saves material costs. Comprehensive calculations can significantly improve the economic benefits of the project. Social benefits: The high-quality, ultra-flat, wear-resistant floor created by this method can effectively improve the performance and durability of the building, reduce the cost of later maintenance and renovation, provide the society with better building space, and create good social benefits. Environmental benefits: By implementing a series of environmental protection measures, such as dust control, noise control, and reasonable disposal of waste, the pollution of the surrounding environment during the construction process is reduced, which conforms to the concept of green environmental protection and sustainable development, and produces positive environmental benefits.  

    The determination of the initial setting time of concrete and the entry timing of laser levelings are directly related to the quality, efficiency and cost of floor construction. Now I will provide you with a detailed analysis of these two core points. The "initial setting" of concrete is a physicochemical process, referring to a point in time when concrete begins to transform from a plastic state to a solid state, rather than a period of time. In terms of standards, the initial setting time refers to the period from the moment water is added and mixed until the concrete loses its fluidity and begins to set. Judgment methods and criteria This is the method stipulated in the national standard (GB/T 50080), which is usually carried out in the laboratory or at important construction sites. Method: Use a penetration resistance meter to penetrate the mortar screened out from the concrete mixture at a specified speed. When the penetration resistance reaches 3.5MPa, the corresponding time is the initial setting time. Advantages: The data is precise, objective and reliable. Disadvantages: It requires dedicated equipment, the operation is rather complicated, and it is not suitable for on-site rapid judgment. In actual construction, workers and technicians mainly rely on the following empirical methods to make judgments: Acupressure method (the most classic) : Apply a slight pressure to the concrete surface (usually with the thumb). The criterion for judgment: If, after pressing with a finger, a clear mark about 2-3 millimeters deep can be left on the surface, and the concrete is not sticky to the hand, with no obvious water marks or slurry overflow around, it is considered to have reached the initial setting state at this time. State analogy: It feels like moist clay or plasticine. Scratch method Make a mark on the concrete surface with a nail, a screwdriver or your finger. The criteria for judgment: The scratch marks are clear, the edges are neat, and the bottom of the scratch can maintain its shape and will not be quickly filled and healed by the slurry. Footprint method A person walks on the concrete and observes the footprints. Judgment criteria: The depth of the footprints should be around 5 to 10 millimeters, and there should be no obvious cracking or excessive bleeding around the footprints. Vibration rod insertion method Insert the small vibrator into the concrete and then pull it out. The criterion for judgment: The hole formed after being pulled out can basically remain in its original state and will not collapse and close rapidly. Important note: The on-site experience method requires construction personnel to have certain experience. The best practice is to make a comprehensive judgment by combining multiple methods and compare it with the estimated initial setting time provided by the laboratory. The entry timing of the laser leveling must be closely coordinated with the setting state of the concrete. Entering the market too early or too late can lead to serious problems. Question Sinking: The tracks or wheels of the leveling may get stuck in the concrete, causing deep ruts and disrupting the flatness. Bleeding: The equipment's rolling will force water and fine particles to float up, forming a surface slurry layer, which leads to dusting, sanding and insufficient strength in the later stage. The concrete cannot support the weight of the equipment, and the leveling head cannot be effectively leveled. Instead, it will disrupt the concrete. Condition description: The fingerprinting mark is very deep (>5mm), or the footprint is deeply sunken, and the scratch heals rapidly. Question Construction difficulties: The resistance of the leveling machine's movement is huge, the engine load is high, and it may even be unable to move. Poor surface quality: The flat head cannot effectively smooth out the already hardened surface, leaving marks of roughening and cracking, which damages the integrity of the surface. Poor joint: It cannot bond well with the subsequent poured concrete, resulting in cold joints. Ineffective compaction: The concrete has lost its plasticity, and the vibration of the leveled head cannot make it compact again. Condition description: There is almost no mark when pressed by finger, or a very strong force is needed to leave a shallow mark. The edge of the scratch will crack. The laser leveling should be put into operation when the concrete reaches the initial setting state, or slightly earlier than the initial setting (that is, close to the initial setting but not yet fully reached). Specific timing to grasp Core standard: When using the finger press method and the depth of the finger press impression is around 3-5mm, it is the best time for the leveling to enter the site. Operation process connection: The ideal construction process is: The preparatory processes: concrete spreading, initial vibration, and leveling with scraping bars have been completed. Wait for the right moment: Let the concrete stand naturally, bleed water and evaporate, gradually developing towards the initial setting state. During this period, workers can carry out manual operations such as edge and corner treatment. Judgment and entry: The construction supervisor continuously observes the condition of the concrete. Once it reaches the aforementioned "golden finger pressure standard", they immediately direct the laser leveling machine to enter the site. High-efficiency operation: The leveling, with its highly efficient functions of scraping, vibrating and leveling, can quickly complete large-scale operations when the concrete is still plastic but capable of supporting the weight of the equipment at its optimal state. Prediction is key: Before construction, it is necessary to understand the mix ratio of the concrete to be used and the estimated initial setting time measured in the laboratory (for example, at 20℃, the initial setting time of ordinary concrete is approximately 4 to 6 hours). This provides a time reference for on-site judgment. Environmental factors: Temperature, humidity and wind speed have a significant impact on the initial setting time. High temperature, strong wind and low humidity will shorten the initial setting time. It is necessary to prepare in advance to reduce the waiting time. Conversely, it will be extended. Personnel and Communication: A designated person (such as a foreman or technician) must be assigned to determine the initial setting time and maintain smooth communication with the equipment operator. It's better to arrive a little earlier than too late: When it's impossible to make an accurate judgment, entering the site a little earlier (the concrete is slightly softer) might just require dealing with the track indentations. However, if the entry is too late and the concrete becomes too hard, the quality problems caused are almost irreversible and the handling cost is extremely high. In short: When you "feel" the concrete with your hand and it feels like a moist and solid piece of clay, that's the best time for the laser leveling to shine. Accurately seizing this opportunity is the core technology for creating high-level and high-quality concrete floors. 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.