Project Overview

Macao Special Administrative Region Nanguang Trading Co., Ltd. plans to transform an industrial building to which it belongs. It will be transformed from a comprehensive industrial building for office and industrial purposes into a commercial cold storage with an ideal capacity of about 1,000 tons. The building is named CTS Industrial Building. The structure is a cast-in-place reinforced concrete frame structure system, and all floors are cast-in-place reinforced concrete slabs. The frame structural column, beam, and slab concrete have a strength grade of B225, and the strength of reinforced steel is A40N. The frame structure filling wall uses brick masonry. The original structure design foundation form of the building is the under-column platform plus drive-in precast square pile pile foundation. The gross area of the building is 3685.15 square meters, with an average gross area of about 650.00 square meters per floor. There are five floors above the ground, no basement, and the roof water tank is partially six floors. The height of the first floor of the building is 5.00m, the height of the second to fifth floors is 3.50m, the height of the roof cornice is 19.00m, and the height of the partial roof of the water tank is 4.20m.

Old building structure test

The overall strength of the building structure is good, which meets the safety and load-bearing capacity requirements of structural transformation, but there is a certain degree of development of concrete carbonization and steel bar corrosion in local locations, which has certain hidden dangers to the normal use conditions after structural transformation. During structural transformation, a comprehensive investigation should be conducted on the crack development of the structure and the carbonization of the concrete. The corrosion of the steel bar should be fully investigated. The local position of the concrete carbonization development and the development of the steel bar corrosion should be pressure-infused with epoxy resin to prevent the further development of the steel bar corrosion . For the man-made damage parts that have occurred in the building, structural repairs should be carried out to restore normal use function.

Reinforcement plan

1.The vertical and diagonal cracks at the bottom of the beam and the slab affect the bending capacity of the reinforced concrete with carbon fiber cloth for reinforcement;

2.Reinforced concrete with vertical cracks on the upper part of the beam and plate that affects the negative bending moment bearing capacity is reinforced with carbon fiber cloth pasted on the upper part of the beam and plate

3.The beams with diagonal shear cracks in the original beams are reinforced with carbon fiber cloth U-shaped hoop;

4.The primary and secondary beam joints with cracks are reinforced with carbon fiber cloth U-shaped hoop;

5.The newly opened floor slab opening is reinforced with carbon fiber cloth at the side of the opening.

Selection of materials for structural reinforcement

Horse carbon fiber 200g and epoxy

In conclusion

Carbon fiber cloth reinforcement technology is a relatively new reinforcement technology. In the reinforcement of concrete structures, carbon fiber cloth is mainly used to share the stress of the steel bars, that is, the main function of carbon fiber cloth is to improve the tensile strength of structural members. Carbon fiber reinforcement is easy to construct, reduces labor costs, and has good corrosion resistance, saving maintenance costs. At present, due to its excellent reinforcement effect, carbon fiber reinforcement can be more and more widely used in Hong Kong and Macau.