Special composite cementitious material for high-grade concrete of bridge expansion joints and thin-shell structures

Abstract

The invention provides a special composite cementitious material for the high-grade concrete of bridge expansion joints and thin-shell structures. The invention aims to solve the problems that as the mixing amount of the admixture material of the common Portland cement is little and the corrosion resistance is poor, and the concrete of highways and railway bridge expansion joints is damaged. The key points of the material are as follows: the cementitious material mainly comprises ground general Portland cement clinker, fly ash, slag powder, volcanic ash, silicon ash and gypsum, which are homogenized and mixed to obtain the cementitious material, wherein the total weight of fly ash, slag powder, volcanic ash and silicon ash accounts for 50-60% of the total weight of the cementitious material. The invention has the following positive effects that: the mixing amount of the admixture material is increased, and the components of the cementitious material are changed while the performances are obviously increased.

Description

technical field [0001] The invention relates to a cement, in particular to a high-grade composite gelling material specially used for thin-shell structure concrete such as highways, high-speed railway bridge expansion joints, bridge decks, and anti-collision walls. Background technique [0002] At present, the cementitious material used in bridge concrete in my country is mainly ordinary Portland cement. According to the national standard GB175-2007, the mix ratio is as follows: the sum of clinker and gypsum accounts for 80-95%, and the balance is admixture (the admixture mentioned in this article refers to materials other than clinker and gypsum in cement), Generally, it is one or more of granulated blast furnace slag, slag powder, pozzolanic admixture and fly ash, accounting for 5-20%. [0003] With the continuous development of highway and railway construction, the traffic volume and vehicle load increase, the bridge load is getting heavier and heavier, resulting in vary...

AI Technical Summary

Problems solved by technology

Ordinary Portland cement mixture has a small amount, a single component, and low quality and poor compactness, resulting in weak carbonation and erosion resistance of concrete, and insufficient durability, resulting in damage to highways, railway bridge expansion joints, etc., and this It also causes greater repeated load impacts on heavy-duty vehicles, worsens the driving conditions, and sharply reduces the service life of the bridge

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