Concrete composite expanding agent

Abstract

The invention discloses a concrete composite expanding agent which is prepared from the following mixed substances in parts by weight: 35-42 parts of coal ash, 12-15 parts of gypsum powder, 3-5 parts of quick lime, 2-8 parts of alunite and 16-22 parts of calcium sulphoaluminate. The concrete composite expanding agent has the beneficial effects that the admixture amount is low, the expansion rate is more than the expansion rate of UEA (in market) with the admixture amount of 12%, the alkali amount is far lower than the alkali amount of 1.7-2.2% of a U-shaped expanding agent, which is of great significance; as the admixture amount is reduced, the early-stage strength and the later-stage strength are not affected, and the purpose of equivalent substitute for cement is achieved in deed; the concrete slump loss is not increased, and good construction properties are achieved.

Description

Technical field [0001] The invention involves a concrete composite expansion. Background technique [0002] The expansion is a chemical exterior, which is added in the cement. When the cement is condensed and hardened, the volume expansion, the rejuvenation contraction and the stress of the tensioned steel bars and the full filling of the cement gap.The traditional expansion agent has low expansion rate and high alkali content, which is easy to adversely affect the later intensity. Invention content [0003] The purpose of the present invention is to provide a composite expansion agent with a high expansion rate and low alkali content in the above existing technologies. [0004] In order to achieve the above purposes, the technical solution provided by the present invention is: a concrete composite expansion agent, which is obtained by mixing the following substances according to the weight of the weight: 35-42 copies of the ash, 12-15 parts of gypsum powder, 3-5 raw lime 3-52-8...

AI Technical Summary

Problems solved by technology

The traditional expansion agent has low expansion rate and high alkali content, which will easily have an adverse effect on the later strength