What is cement cushion block? Introduction to concrete bearing capacity of cement cushion block

Many people do not know what the cushion block is, but it plays an unimaginable role because a small cushion block carries the weight of the whole building. If you want to build a solid building, you must have a small cushion block.

The cushion blocks used in different scenarios also have certain differences, such as cement cushion blocks, concrete cushion blocks, reinforcement cushion blocks, etc. The cement cushion block manufacturers take various scenarios into consideration during the R&D and manufacturing process.

What is the cement cushion block?

Cement cushion block It refers to the use of pins and adhesives to fix on the back of the stone plate to provide protection and a concealed horizontal support surface. Let's take a closer look.

1. Maintenance of structural durability: the thin protective layer in the concrete is easy to penetrate damp gas and water, which may cause corrosion and expansion of reinforcement, thus causing damage to the concrete and affecting the use and structural safety.

2. The protective layer under the action of external force has anchoring force to the reinforcement. The anchoring force between concrete and reinforcement is used to closely combine the two and participate in the work together. When the protective layer is too thin or missing, its anchoring force will be reduced, thus reducing the resistance of the structure to axial force and bending moment. If the protective layer is too thick, the concrete surface is easy to produce cracks, which will affect the stress of reinforcement in the concrete.

3. Calculation formula of flexural bearing capacity from normal section

M ≤ a l fcbx (h0 - x/2)+fy'AS' (ho - a s') - (σ pO '- fpy') A p '(ho - a p'), it can be seen that when the effective height h0 of the section decreases due to the excessive thickness of the gluten protective layer, the bending bearing capacity of the section will be reduced. It can be seen that the thickness of the protective layer is an important factor affecting the bearing capacity of the structure.

4. The concrete of the fire protection layer has a certain heat insulation effect, which can protect the steel bars that are easy to soften in case of fire. If the thickness of the protective layer is too thin, it is easy to crack in the high temperature environment, resulting in the strength reduction of the steel bars due to overheating, thus damaging the overall structure. In 2003, a project in Hengyang, Hunan Province, due to the high temperature and high heat generated by the fire, the reinforcement softened and collapsed, causing heavy casualties.