4.3.1. Introduction to technology.
Foam concrete is a new type of lightweight and high-strength insulation material containing a large number of closed pores formed by mixing and stirring through the foaming system of the foaming machine, fully foaming the foaming agent by mechanical means and adding the foam to the slurry made of cement, aggregate, admixture, admixture and water, mixing and stirring, and then carrying out cast-in-situ construction or mold forming through the pumping system. The foam concrete is filled with a large number of closed, uniform, fine circular pores, low density, light weight, low elastic modulus, good thermal insulation performance, sound absorption and sound insulation performance and shock absorption performance, in addition, foam concrete is cement as the main material, sand and gravel as auxiliary materials, good fire resistance, good pumpability in the construction process, a large number of industrial waste residue, low cost, waste into treasure, environmental protection and other advantages. It is suitable for building structures such as internal and external walls, roofs, floors, columns, etc., and is a new type of building energy-saving material that is waste-relieving, environmentally friendly, energy-saving, inexpensive and non-combustible.
4.3.2 technical points.
Before pouring foam concrete, sprinkle water to moisten the floor base layer to ensure the cohesiveness of the foam concrete and the floor base layer, and the sprinkling water is even, and it is advisable to have no water on the ground.
The foam concrete pouring should be operated in a certain order, and the height of the discharge port from the base should not exceed 1m. When the concrete is poured in a large area, the method of partition and piece by piece pouring is adopted, and the construction surface is divided into a number of small pieces with a template to be constructed piece by piece, so as to prevent the flow of surface foam concrete from affecting the laying thickness and the light collection effect. It is also possible to adopt the pouring method of segmented layering and comprehensive layering, and the thickness of a pouring should not exceed 20cm, otherwise it should be poured in layers, so as to avoid the collapse of the lower lightweight foam concrete slurry under excessive pressure, and after its initial setting, the secondary pouring is carried out. When the roof slope is 2%, the slope finding construction with foam concrete needs to be assisted by formwork.
When the foam concrete poured in the separation area reaches the calibrated height, it is scraped flat with an aluminum alloy scraper, and the place with honeycomb is repeatedly scratched several times to eliminate the honeycomb, and the height is controlled within 1cm to ensure that the pouring surface is smooth. When the foam concrete is paved with sectional flow operation, the paving thickness is 1 2 1 3 times of the actual thickness, and then scraped flat with an aluminum alloy scraper. During summer construction, due to the high outdoor temperature, when the pouring thickness reaches the calibrated height, it is necessary to collect the light immediately, so as to avoid the surface of the foam concrete due to the rapid loss of water and the appearance of surface matte surface.
After scraping, it should not be disturbed before the final setting, and after the initial setting of the foam concrete, cover the plastic sheet in time to keep the slurry moisture to prevent cracking.