Corrosion resistant cast-in-place pile concrete in high and cold soft ground regions

Abstract

The invention provides corrosion resistant cast-in-place pile concrete in high and cold soft ground regions. The concrete is characterized by being prepared from Portland cement, a mineral admixture of fly ash accounting for 15-20% of Portland cement by weight and ground slag accounting for 25-30% of Portland cement by weight, a water reducing agent which has water-binder ratio less than 0.4 and accounts for 1% of Portland cement by weight, and air entraining agents accounting for 3 / 10000 of Portland cement by weight by a traditional process. The prepared concrete has strength grade of C30 or C40, air content of (2.5+ / -0.5)%, total alkali content not more than 3.0kg / m<3>, impermeability grade not less than P10, freezing resistance not less than F50, sulfate corrosion resistance coefficient not less than 0.75 and 28d diffusion coefficient of chloride ion (D<RCM>) not more than 6X10<-12>M<2> / s. The compactness of the concrete can be effectively improved, permeation of ions with corrosivity can be prevented, the freezing resistance of the concrete can be improved, and the requirement for durability can be met, thus the concrete cast-in-place pile foundation with the strength grade of (C30, C40) is applied to high and cold soft ground regions with corrosive media such as SO4<2-> and Cl<->.

Description

technical field [0001] The invention relates to an anticorrosion method for the foundation of a power transmission line, in particular to a concrete anticorrosion formula for cast-in-situ pile foundations in the high cold and strong corrosive geological conditions of the power transmission line. Background technique [0002] The power transmission line project located in the northwest region where saline soil is widely distributed will inevitably pass through the soft ground area with strong corrosive geological conditions. The use of traditional excavated foundations in these areas not only has a large construction area and a long period, but also seriously damages the natural soil, which is not conducive to environmental protection. It is hoped that the cast-in-place pile foundation with undisturbed soil can effectively solve these problems; However, in the current "Code for Anti-corrosion Design of Industrial Buildings" GB 50046-2008, Article 4.9.5 stipulates: in S...

AI Technical Summary

Problems solved by technology

The use of traditional excavation foundations in these areas not only has a large construction area and a long period of time, but also seriously damages the natural soil, which is not conducive to environmental protection. It is hoped that the cast-in-place pile foundation with undisturbed soil can effectively solve these problems; However, in the current "Code for Anti-corrosion Design of Industrial Buildings" GB 50046-2008, Article 4.9.5 stipulates: in SO4 2- , Cl - Under the action of medium, if the corrosion level is strong corrosion, the concrete pouring pile foundation should not be used