One-step forming construction method of high-precision wear-resistant floor without cutting based on concrete laser leveling technology

Ⅰ. Features of the method

1. High precision:

- Using laser leveling technology, the laser transmitter generates a precise and stable plane reference. The laser receiver is installed on the leveling machine to sense the deviation in real time, so that the leveling machine automatically adjusts the scraper height to ensure that the floor flatness error is extremely small, which can generally be controlled within ±1.5mm, and can meet the needs of high-end industrial plants, electronic chip manufacturing workshops and other places with strict requirements on flatness.

2. No cutting seams:

- Optimize the concrete mix ratio, add appropriate amounts of expansion agents, fibers and other admixtures, reduce the shrinkage stress during the hardening process of concrete, and cooperate with the carefully designed construction process, so that the floor does not need to set expansion joints in a large area, which is not only beautiful but also reduces the later maintenance cost, and avoids the accumulation of dust and debris caused by cutting seams.

3. Good wear resistance:

- In the initial setting stage of concrete, wear-resistant materials such as corundum and metal aggregates are evenly spread, and a special trowel is used to closely combine with the floor to form a hard and wear-resistant surface layer. The wear resistance can be several times higher than that of ordinary concrete floors. It is suitable for places with frequent wear and tear such as heavy traffic areas, warehouses, and logistics centers.

4. One-time molding:

- From base treatment, concrete pouring, leveling to wear-resistant material spreading, troweling and finishing, the processes are closely connected and completed in one go, avoiding the problem of poor interlayer bonding caused by layered construction, improving the overall strength and durability of the floor, and reducing the construction period. It can usually shorten the construction period by 1/3 - 1/2 compared with traditional processes.

Ⅱ. Scope of application

Applicable to indoor and outdoor concrete floor projects with large areas and high requirements for flatness and wear resistance, such as various large industrial plants, logistics storage centers, airport terminals, exhibition halls, parking lots, etc., especially suitable for places where obvious expansion joints are not expected to affect the appearance or use function.

Ⅲ. Process principle

1. Laser leveling principle:

- The laser transmitter emits a rotating laser beam to form a high-precision horizontal control surface. The laser receiver installed on the leveling machine continuously captures the laser signal, compares the actual elevation of the floor with the laser plane benchmark, and transmits the generated deviation signal to the control system. The control system drives the hydraulic actuator of the leveling machine to adjust the scraper, vibrator and other components in real time to accurately level and vibrate the concrete to achieve high-precision leveling.

2. Seam-free principle:

- On the one hand, by optimizing the concrete mix ratio, selecting low-hydration hot cement, adding an appropriate amount of expansion agent (such as calcium sulfoaluminate expansion agent) to compensate for concrete shrinkage, adding polypropylene fiber to enhance concrete toughness and inhibit the generation of microcracks; on the other hand, during the construction process, strictly control the concrete pouring temperature, vibration method and curing conditions, reasonably arrange the construction sequence, reduce the temperature difference between the inside and outside of the concrete and stress concentration, so that the floor itself has the ability to resist shrinkage and deformation, thereby meeting the requirements of no seam cutting.

3. Abrasion-resistant principle:

- The surface of concrete in the initial setting stage has a certain viscosity. At this time, the spread wear-resistant material can be embedded in the surface of the concrete. With the subsequent leveling and finishing operations, the wear-resistant material and the concrete form a solid whole. Wear-resistant materials such as corundum and metal aggregates have high hardness and strong wear resistance, forming a wear-resistant protective layer on the surface to protect the main concrete of the floor from wear.

Ⅳ. Construction process and operation points

1. Construction preparation:

- Technical preparation: Familiar with the construction drawings and technical specifications, formulate detailed construction plans, and conduct technical briefings.
- Site preparation: Clean up the site debris and accumulated water, level the base layer, and if the base layer is soft soil, it needs to be reinforced; set up a temporary drainage system for construction; plan the concrete pouring and leveling route according to the site area and shape.
- Material preparation: Purchase high-quality cement, sand, gravel, admixtures, wear-resistant materials, etc. according to the design requirements, inspect the raw materials to ensure that they meet the quality standards; prepare sufficient construction water and electricity.
- Equipment preparation: Debug concrete laser leveling machine, concrete mixing equipment, transportation equipment, wear-resistant material spreader, trowel, etc. to ensure the normal operation of the equipment; calibrate the laser system so that the laser plane it emits is consistent with the designed elevation of the floor.

2. Base treatment:

- Thoroughly clean the surface of the base to remove pollutants such as dust and oil; compact the base with a roller or tamping machine to achieve a compaction degree of more than 90%; repair and fill local low-lying areas and potholes with concrete or mortar to ensure that the flatness error of the base does not exceed ±10mm.

3. Concrete pouring:

- Accurately weigh the raw materials according to the designed mix ratio, use a forced mixer to mix the concrete, and the mixing time is not less than 90 seconds to ensure the uniformity of the concrete; transport the concrete to the construction area by pumping or unloading, control the pouring speed, avoid concrete segregation, and the pouring thickness is slightly higher than the designed floor elevation by 10-20mm to reserve space for leveling.

4. Laser leveling:

- Start the laser leveling machine and make it move forward at a uniform speed of 1-2m/min; the operator adjusts the scraper height and vibration frequency of the leveling machine in real time according to the feedback signal of the laser receiver to ensure that the concrete surface is flat and compacted; the leveling work of adjacent areas should be completed before the initial setting of the concrete, and the overlapping construction width should not be less than 10cm to ensure the integrity of the floor.

5. Spreading of wear-resistant materials:

- When the concrete is initially set (generally there are slight footprints when stepping on it, and the sinking depth is about 3-5mm), use a special spreader to evenly spread the wear-resistant materials on the floor surface according to the specified amount, and the spreading thickness is generally 3-5mm; during the spreading process, pay attention to controlling the spreading speed and direction to avoid accumulation or leakage of wear-resistant materials, and ensure that the spreading uniformity reaches more than 90%.

6. Smoothing and finishing:

- After spreading the wear-resistant material, use a trowel to smooth it immediately. The trowel should run in a crisscross pattern to fully blend the wear-resistant material with the concrete. The number of smoothing passes should be no less than 3 times. As the concrete continues to harden, when there is no water stain on the surface and it feels slightly hard when pressed with fingers, it should be smoothed manually. Aluminum alloy rulers, trowels and other tools should be used to make the floor surface bright and smooth.

7. Maintenance:

- After smoothing and finishing, the floor should be maintained in time by covering with plastic film, spraying curing agent or laying water straw mats. The maintenance time should be no less than 7 days. During this period, the concrete surface should be kept moist to avoid water loss and cracks. Warning signs should be set up during the maintenance period to prohibit vehicles and pedestrians from passing on floors that do not meet the strength requirements.

Ⅴ. Quality Control

1. Flatness Control:

- Calibrate the laser system before construction to ensure the accuracy of the laser plane; regularly check the flatness with a 2m ruler and a feeler gauge during construction, at least once every 100-200 square meters, and adjust the leveler in time if deviation is found; use a laser flatness meter to fully test the flatness of the floor after finishing to ensure that it meets the design requirements.

2. Wear Resistance Control:

- Strictly select wear-resistant materials according to design requirements and check the quality certification documents of wear-resistant materials; supervise the spreading amount and uniformity during spreading to ensure that the specified requirements are met; after maintenance, on-site wear resistance tests can be carried out, such as grinding a certain area with a grinding wheel, observing the wear condition, and judging whether the wear resistance meets the standard.

3. Shrinkage Crack Control:

- Optimize the concrete mix ratio, control the cement dosage and water-cement ratio; monitor the concrete pouring temperature to avoid high-temperature pouring; strengthen maintenance and control the temperature difference between the inside and outside of the concrete; regularly inspect the floor, and if fine cracks are found, use epoxy resin and other materials to repair them in time.

Ⅵ. Safety measures
 

1. Provide safety training to construction personnel to familiarize them with the operation methods and safety precautions of construction equipment, such as the safety operating procedures of laser levelers, concrete mixers and other equipment.
2. Set up obvious safety warning signs at the construction site to divide the construction area and non-construction area to prevent unrelated personnel from entering the construction danger zone.
3. Regularly check the safety performance of construction equipment, such as electrical insulation, mechanical protection devices, etc., to ensure the normal operation of the equipment and avoid safety accidents caused by equipment failure.
4. Provide construction personnel with necessary personal protective equipment, such as safety helmets, safety shoes, gloves, etc., to ensure the personal safety of construction personnel.

Ⅶ. Environmental protection measures
 

1. Classify and collect solid waste such as concrete residues and discarded wear-resistant material packaging bags generated during the construction process, and transport them to designated garbage disposal sites regularly.
2. Reasonably arrange construction time to avoid high-noise concrete mixing, equipment operation and other operations during residents' rest time. If necessary, take noise reduction measures, such as installing silencers on equipment.
3. Control dust on the construction site, such as covering the material storage area, closing the transport vehicles, regularly sprinkling water to reduce dust, and keeping the construction site clean.

Ⅷ. Benefit Analysis
 

1. Economic Benefit:

- The one-time molding process shortens the construction period, reduces labor costs, equipment rental costs, etc.; no cutting reduces the later maintenance costs, such as cutting, caulking material costs and labor maintenance costs; wear-resistant flooring increases the service life of the flooring, reduces the frequency of flooring replacement, and the overall economic benefits are significant.
 

2. Social Benefit:

- It provides high-quality flooring solutions for various large-scale projects, meeting the needs of rapid development of modern industry, logistics and other industries; it reduces noise, dust and other pollution during construction, which is conducive to environmental protection and sustainable development of urban construction.

Ⅸ. Application Examples
 

In a large electronic chip manufacturing plant construction project, this construction method was used to successfully create a high-precision, no-cutting, wear-resistant factory floor. The construction area reached 50,000 square meters, and the flatness error was controlled within ±1mm, meeting the stringent requirements of chip manufacturing equipment for floor flatness. In the subsequent years of use, the floor had good wear resistance and no obvious cracks appeared, providing a solid guarantee for the efficient production of the factory. For example, in a certain international logistics and warehousing center project, this construction method also performed well, and a large area of ​​floor was built quickly and efficiently. The seam-free design improved the aesthetics and practicality of the warehouse and was highly recognized by the owner.