A kind of concrete self-curing type micro-expansion agent and using method

Abstract

The invention relates to the technical field of cement concrete products, and relates to a concrete self-curing micro-expansion agent and a use method thereof. The concrete self-curing micro-expansion agent of the present invention is composed of metakaolin (mass fraction 50%~80%), Mg‑Al‑CO3 intercalated hydrotalcite (mass fraction 5%~20%), bentonite (mass fraction 10%~30%) %), CaSO4 (mass fraction 2%~8%), and the rest is tricalcium phosphate, whose total mass meets 100%. Among them, metakaolin and Mg‑Al‑CO3 intercalated hydrotalcite are all calcined at a certain temperature. , the self-curing micro-expansion agent is mixed with 4%~15% to replace cement or other cementitious materials. After the concrete is mixed and formed, it no longer needs external water supplementation for maintenance, and the concrete can achieve micro-expansion effect and related properties. Meet the requirements of GB 2349-2009 "Concrete Expansive Agent".

Description

technical field [0001] The invention relates to the technical field of cement concrete products, and relates to a concrete self-curing micro-expansion agent and a use method thereof. Background technique [0002] With the rapid development of concrete technology, the demand for expansive concrete in the construction market is increasing, which also promotes the development of expansive agents. For different types of expansive agents to play an expansive effect in concrete, their early adequate maintenance is very important, and some concrete structures are difficult to meet the curing requirements of expansive agents, and the structure itself requires concrete to have certain expansive properties. Typically, if the application is more Concrete-filled steel tube structures are becoming more and more widespread. In order to prevent the shrinkage of the concrete in the structure from causing the concrete to separate from the inner wall of the steel tube, the design usually requ...

AI Technical Summary

Problems solved by technology

For different types of expansive agents to play an expansive effect in concrete, their early adequate maintenance is very important, and some concrete structures are difficult to meet the curing requirements of expansive agents, and the structure itself requires concrete to have certain expansive properties. Typically, if the application is more Concrete-filled steel tube structures are becoming more and more widespread. In order to prevent the shrinkage of the concrete in the structure from causing the concrete to separate from the inner wall of the steel tube, the design usually requires the use of micro-expansion concrete. At present, most concrete companies can only try to achieve micro-expansion of concrete by adding ordinary expansion agents. , and because the surface of steel pipe concrete is closed by steel pipes, water cannot be replenished. At the same time, due to the low water-binder ratio of concrete (the concrete grade of steel pipe concrete structure is usually higher), the water in the system is insufficient, so ordinary expansion agents cannot be effectively maintained. play its due role