Comparative analysis of foam concrete and ceramsite concrete materials

Foam concrete energy-saving insulation material uses ordinary Portland cement, foaming agent, and water as the main raw materials. In the production process, physical and mechanical methods are used to send the foaming agent aqueous solution into the high-pressure vessel, and the foaming agent aqueous solution is fully foamed through the foaming system to prepare foam, and then the foam is evenly mixed with the stirred cement slurry, and the cement The silicate molecules in the slurry adhere to the foam liquid film and solidify after 15 to 60 minutes of initial setting to form a porous foam concrete material (the stability of the foam should support the silicate molecules not to burst during the initial setting period and not deformation). The material has unique performance characteristics such as being lightweight, inorganic and environmentally friendly, and can be cast in place. The flame retardant level is Class A (non-flammable).

Foam concrete roofing materials and ceramsite concrete Roofing materials are both lightweight concrete materials, with basically the same design structure and functions (different thicknesses), but there are big differences in product performance and production processes.

1. Comparison of main technical performance:

Comparison of ceramsite concrete and foam concrete materials

Note: 1. Reference standard: “JGJ 51- 2002 “Lightweight Aggregate Concrete Technical Regulations”, “Q/NHT001-2007 Foam Concrete Products” Enterprise Standard, “Foam Concrete” National Product Industry Standard – Draft for Comments;

2. Ceramic Concrete Material Cushion Applicable densityThe grade is 600~700;

3. The applicable density grade of foam concrete material cushion is 300~600 (grade A03~A06).

It can be seen from the above table that there are some differences in the performance of the two materials. Ceramsite concrete uses ceramsite, cement, sand, and water as the main raw materials. The strength and density of ceramsite concrete vary depending on the quality of the ceramsite. Generally, it is not less than 560KG/m3. The relative thermal conductivity is large, but the strength is good. ; Foam concrete uses cement, water, and foaming agent as the main raw materials. It is mechanized and operated. The density control is relatively accurate (300~500KG/m3). The thermal conductivity is low and is more suitable for energy-saving building requirements. Its compressive strength is above 0.4Map. Meets general underlay requirements.

It can be seen from the above comparison that using foam concrete as roof insulation and slope finding material is lighter and more energy-saving.

2. Construction technology comparison

1. Ceramic concrete roof construction technology

① Base treatment: Before pouring the ceramsite concrete cushion, the concrete floor base layer To deal with it, use a chisel to remove loose concrete, mortar, etc. bonded to the base layer, brush off the cement slurry with a wire brush, and then sweep it away with a broom.

② Find the elevation control line to bounce horizontally: According to the +50cm horizontal elevation line on the wall, measure the cushion elevation downwards. If possible, bounce it on the surrounding walls.

③Ceramsite sieving and water blocking: In order to remove debris and fine powder in the ceramsite, the ceramsite must be screened twice after entering the site. Use a large pore size sieve (sieve hole 30mm) for the first pass, and a small pore size sieve (sieve hole 5mm) for the second time to control the 5mm particle size content to no more than 5%. Before pouring the cushion, the pottery Water the grain pile evenly to suffocate the ceramsite. The time of water suffocation should be no less than 5 days.

④ Stirring: First, measure the aggregate, cement, water and admixtures by weight. The allowable measurement deviation of aggregates should be less than ±3%, and the allowable measurement deviation of cement, water and admixtures should be less than ±2%. Since the ceramsite is water-stuffed in advance, the water content of the mix ratio is adjusted based on the moisture content of the ceramsite before mixing. The mixing time is slightly longer than ordinary concrete, about 3 minutes.

⑤Laying, vibrating or rolling: The thickness of the poured ceramsite concrete cushion shall not be less than 60mm, and the strength grade shall not be less than C10. Sprinkle water on the cleaned base to moisten it. Apply a cement slurry bonding layer with a water-cement ratio of 0.4 to 0.5. Spread the mixed ceramsite concrete, use a shovel to spread the concrete on the base, use the prepared leveling pier as a standard to spread the ash, 3mm higher than the leveling pile, and then use a flat vibrator to vibrate and level. If the thickness is thin, you can use a shovel and a special wooden clapper to compact it as you lay, and then level it with a large bar, rub it flat with a wooden trowel, or compact it with an iron roller. When joining the joints, a cement slurry (W/C is 0.4~0.5) bonding layer should be applied to the construction joints before pouring continues.

⑥Sprinkling and curing should be carried out after pouring. The next process can only be carried out after the strength reaches 1.2MPa. During winter construction, the ceramsite should not be exposed to freezing when sprinkled with water, and should be covered with sufficient insulation materials. The indoor operating temperature should be above +5°C.

2. Foam concrete roof construction technology

① Base layer treatment: Clean the roof debris and sweep it with a broom. No oil stains are allowed on the surface.

② Find the elevation control line to bounce horizontally: According to the +50cm horizontal elevation line on the wall, measure the cushion elevation downwards. If possible, bounce it on the surrounding walls.

③Use a special machine for foam concrete to put the cement into the loading machine, prepare the foaming agent at the same time, start the equipment to make foam concrete slurry and pump it to the working surface to achieve the corresponding thickness.

④ Use a ruler to smooth the foam concrete slurry and find the slope according to the position of the spring line.

⑥After the pouring is completed, it will be cured naturally, and the next process can be carried out after 72 hours. Sprinkling and curing are required 24 hours after pouring is completed in summer. During winter construction, the uncured foam concrete materials must not be frozen and should be covered with sufficient insulation materials.

It can be seen from the above chart that during the construction process: in the construction process of ceramsite concrete roofing, ceramsite sifting, mixing and other processes require manual operations. The laying process requires the use of racks, hanging trays and other facilities at the construction site, and the construction time is long; the foam concrete roof construction is made mechanically, and is directly pumped to the working surface, and can be sloped and leveled directly with ruler rods, without occupying racks, hanging trays, etc. Dishes and other facilities. It saves a lot of labor and time and improves work efficiency. </p