100% substituted rate recycled aggregate concrete with low slump loss

Abstract

The invention provides 100% substituted rate recycled aggregate concrete with low slump loss, and belongs to the technical field of recycled concrete in constructional engineering. The recycled aggregate concrete includes cement, water, fly ash, granulated blast-furnace slag powder, yellow sand, gel-treated recycled coarse aggregate and a high-effective water reducer according to certain ratio, wherein a gel treatment solution is prepared from a calcium material, a silicon material and water according to certain ratio. Compared with conventional recycled aggregate concrete, the concrete is high in aggregate replacement rate (100%), so that effective utilization of the recycled aggregate is achieved. In addition, the concrete has good initial flowability, and is far lower than regular whole-substituted recycled aggregate concrete in slump time loss, thus satisfying engineering application demand.

Description

technical field [0001] The invention belongs to the technical field of recycled concrete in construction engineering, in particular to a recycled aggregate concrete with a low slump loss and 100% replacement rate. Background technique [0002] It is an important way to realize the effective utilization of waste concrete by screening, crushing and shaping the waste concrete to produce recycled aggregate for the production of recycled concrete. However, judging from the current utilization of recycled aggregate, it is not ideal. Recycled concrete made with recycled aggregates usually has low strength, poor fluidity, and large slump loss over time. The main reason is that recycled aggregates usually have poor grain shape, old mortar and a lot of impurities attached to the surface. The old mortar on the surface will cause the water absorption rate of the recycled aggregate to far exceed that of the natural aggregate, which will affect the fluidity of the concrete, and the poor...

AI Technical Summary

Problems solved by technology

However, judging from the current utilization of recycled aggregates, it is not ideal

Recycled concrete made with recycled aggregates usually has low strength, poor fluidity, and large slump loss over time.

The main reason is that recycled aggregates usually have poor grain shape, old mortar and a large amount of impurities attached to the surface

The old mortar on the surface will cause the water absorption rate of the recycled aggregate to far exceed that of the natural aggregate, which will affect the fluidity of the concrete, and the poor particle shape will also cause the cement slurry to not completely wrap the recycled aggregate, resulting in a decrease in the fluidity of the concrete

In addition, the continuous water absorption of recycled aggregates also causes the slump loss of recycled concrete to far exceed that of natural aggregate concrete

These unfavorable factors above lead to a low substitution rate (usually ≤ 30%) when the mixing station uses recycled aggregates, and the preparation strength is generally not high (C20~C30)

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