A self-locking ecc-clad reinforced concrete column reinforcement method

Abstract

The invention provides a self-locking method for reinforcing reinforced concrete columns with ECC cladding, including fixing the first angle steel and the second angle steel on the four corners of the reinforced concrete column; spacing several steel strands at a certain distance from top to bottom Evenly surround the reinforced concrete column and fix it on the second angle steel to form a steel strand network; apply prestress to each steel strand; spray or smear ECC on the surface of the reinforced concrete column 1, and ECC covers the first angle steel and the second angle steel And a number of steel strands, fill the gap, and complete the reinforcement. Among them, the weight ratio of each component in ECC to cement is fly ash: 0.5~3; fine sand: 0.5~1.5; silica fume: 0~0.1; water: 0.5~2; PVA fiber: 0.02~0.1; water reducer: 0.005~0.02; accelerator: 0.01~0.1, this method can increase the bearing capacity of reinforced concrete columns, and has a greater restraint effect on reinforced concrete columns. And it can effectively prevent the intrusion of water and chloride ions, effectively inhibit the corrosion of steel bars, and also improve the fire resistance of reinforced concrete columns.

Description

technical field [0001] The invention relates to the field of building construction, in particular to a method for reinforcing a self-locking ECC clad reinforced concrete column. Background technique [0002] At present, a large number of reinforced concrete columns in active service in my country have structural performance degradation problems. The main reasons are chemical corrosion (chloride ion corrosion), physical damage (impact), natural disasters such as floods, fires, and earthquakes, and some components have design or construction errors. meet specification requirements. The above problems have seriously affected the safety and usability of the structure. Therefore, the damaged reinforced concrete columns need to be reinforced. [0003] Common reinforced concrete column reinforcement methods include FRP reinforcement method, enlarged cross-section reinforcement method, and bonded steel method. The FRP reinforcement method is to use light and high-strength materials...

AI Technical Summary

Problems solved by technology

The FRP reinforcement method is to use light and high-strength materials such as carbon fiber cloth and glass fiber cloth, combined with epoxy resin glue to paste and wrap on the surface of the column, which acts as a circumferential constraint and improves the bearing capacity of the reinforced column. However, this reinforcement method is limited. Due to the poor high temperature resistance and fire resistance of epoxy resin glue, the glass transition temperature of epoxy resin glue is generally 50-80°C. When the ambient temperature exceeds the glass transition temperature, epoxy resin glue will fail, and FRP will lose its The foundation of the joint action of concrete columns cannot play its role; the method of enlarging the cross-section is to pour a new layer of reinforced concrete reinforcement outside the original column. This method can greatly increase the bearing capacity of the reinforced column, and the construction is simple, but Its disadvantage is that the enlarged cross-sectional area is large and occupies the building area; the steel bonding method is a reinforcement method by pasting steel plates or angle steels outside the structure. The essence of this method is an external reinforcement, which improves the overall reinforcement ratio of the structure. and hoop ratio

This method can obviously improve the bearing capacity, ductility and rigidity of the structure, and the construction is simple and fast, and has little influence on the shape of the structure. However, the structural adhesive used for bonding steel has poor fire resistance and is easy to age. It is easy to cause corrosion problems and affect its performance, so this reinforcement method also has certain limitations.

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