Factory column reinforcement

Project Overview 

The factory building in an industrial zone was originally an 8-story frame structure with a reinforced concrete column section of 500mmx500mm, a concrete grade of C30 strength, and a total of 12 grade II steel bars with a diameter of 25 along the periphery of the column. The original structural load-bearing and anti-seismic fortification of the factory building could not meet the requirements.

After the structural reinforcement design, it is planned to use carbon fiber reinforcement technology to reinforce the flexural strength of some columns of floors 1-2. At the same time, due to the long-term erosion of acid and alkali gas, the protective layer of concrete has been partially peeled off, and the stirrups have been partially rusted. It is necessary to reinforce the lateral restraint of the concrete.

Reinforcement plan

This kind of reinforcement technology is mainly used because the carbon fiber cloth reinforcement has the following advantages:

1. High strength, thin and light, hardly increase the structural weight and cross-sectional dimensions. The tensile strength of carbon fiber sheets is 7 to 10 times that of equivalent cross-section steel plates. The thickness of the finished sheet is only 0.11mm ~ 0.167ram, and its bulk density is 1/4 ~ 1/5 of the steel. And good flexibility, easy to cut, and a wide range of applications. Suitable for any shape

2. Anti-corrosion of acid, alkali and salt media, fatigue resistance, creep resistance, material size stability. After reinforcement, it can greatly improve the corrosion resistance and durability of the structure. It can be applied to the reinforcement of components in various working environments.

3. The construction is simple and fast. The carbon fiber sheet can be directly pasted and wrapped on the surface of the building. The process is simple, without the need for templates and large-scale lifting equipment. It has low requirements on the construction site and is suitable for narrow space operations. Easy to operate. Economical.

4. It can effectively close the cracks of the concrete structure and prolong the service life of the structure.

 5. The use of carbon fiber sheet for reinforcement can maintain the appearance of the original structure to the maximum extent, without affecting the surface decoration, and minimize the traces of repair.

The scheme of pasting two layers of carbon fiber cloth is: the first layer is pasted longitudinally along the axis of the column to improve the bending strength of the column. The second layer is wrapped horizontally along the column to enhance the column's compressive strength, ductility and seismic performance. Considering that the same amount of carbon fiber cloth is used, the effect of stripe wrapping is better than that of the whole wrapping. At the same time, it was bonded to the cross-sectional dimensions of the column, and it was decided to stick a carbon fiber cloth with a width of 300 mm to each side along the axis of the column, with a lap length of 250 mm. The carbon fiber cloth with a width of 300mm is wrapped every 100mm along the column height, and the overlap length is 250mm.