A kind of preparation method of pottery sand for freeze-thaw resistant concrete

Abstract

The invention provides a preparation method for frost-resistant concrete. The preparation method comprises the following steps: soaking pottery sand in glycol or glycerol; then sprinkling an aqueous polyvinyl alcohol solution onto the surface of the pottery sand so as to coat the surface of the pottery sand with a layer of an organic film; and then coating the surface of the pottery sand with a layer of cement paste. According to the invention, the anti-freezing agent glycol or glycerol with substantial low temperature resistance is applied to the concrete, so the freezing point of the aqueous solution is allowed to drop to dozens of degrees lower than 0 DEG C; so the concrete is prevented from liquid-solid phase change of the solution at low temperature; and thus, ice swelling pressure is not generated and a freezing-thawing cycle does not cause destructive damage to the concrete.

Description

technical field [0001] The invention relates to a method for preparing pottery sand for freeze-thaw resistant concrete, which belongs to the technical field of new building materials. Background technique [0002] With the rapid development of social economy, the durability requirements of concrete for buildings are constantly increasing, and the freeze-thaw resistance is an important durability index of concrete. At present, there are two main technical means to improve the freeze-thaw resistance of concrete: one is to lower the freezing point of water by adding some salts to the admixture, and the other is to relieve the ice swelling caused by the solid-liquid phase transition of water by entraining air stress. These two methods have certain limitations. Salts do not lower the freezing point of water much, and generally can only be maintained at a few degrees below zero without freezing. However, when the air-entraining amount is too large, the mechanical properties of c...

AI Technical Summary

Problems solved by technology

These two methods have certain limitations. Salts do not lower the freezing point of water much, and generally can only be maintained at a few degrees below zero without freezing.

However, when the amount of air-entraining is too large, the mechanical properties of concrete will be reduced. If the amount of air-entraining is insufficient, the anti-freezing and thawing effect cannot be achieved. Even if the amount of air-entraining is moderate, the relief of the ice expansion stress can only be maintained within a certain limit.