When building structural component beams, slabs, columns and other diseases occur, treatment measures shall be taken in time, and reinforcement construction shall be carried out when necessary. In actual projects, it is often necessary to make holes in the concrete floor that has been completed, and the hole has a relatively large impact on the floor. After the hole is opened, the stress conditions of the slab have changed, and the rigidity and bearing capacity of the slab will be reduced, and it is usually necessary to adopt reinforcement treatment. So what are the slab reinforcement methods?

Generally, there are several situations where board reinforcement is needed:

1. Insufficient bearing capacity of the floor (usually increased load on the floor, such as adding equipment;

2. The strength of floor slab concrete is unqualified;

3. Renovation of floor openings.

The following reinforcement methods are usually used to reinforce the floor slab:

1.Enlarge the section of the plate to strengthen the method.

The method of increasing the slab section reinforcement is to add a post-pouring layer of reinforced concrete with a thickness of not less than 40mm on the slab surface or the slab bottom. In order to facilitate the construction, the slab surface pouring is often used to form a rigid floor and roof. If it is necessary to use the bottom of the slab to pour the laminated layer, the bottom of the slab must be chiseled and sprayed for construction. The reinforcing steel bars shall be hot-rolled steel bars, and the diameter of the stressed steel bars of the plates shall not be less than 8mm.

2. The floor slab is reinforced with carbon fiber cloth.

The board-bonded carbon fiber cloth reinforcement method is to paste the carbon fiber cloth along the span direction of the board to the tensioned part of the board bottom through structural glue, and the end must be reliably anchored. The advantage is that the carbon fiber cloth has light weight and high strength, and can be pasted in multiple layers. After reinforcement, the weight of the original member is basically not increased, and the structure shape is not affected. It can not only improve the structural bearing capacity but also enhance the rigidity of the structure.

3. The method of sticking steel plate to plate.

In addition to the basic assumption of the bearing capacity of the normal section, the plate-bonded steel plate method to strengthen the flexural member plate should also meet the following requirements:

①. When considering the influence of the secondary force, the hysteresis strain of the steel plate should be determined according to the initial condition of the reinforced member.

②. Before reaching the ultimate state of flexural load-bearing capacity, none of the externally bonded steel plates and the concrete shall be bonded and peeled off.

③. After the reinforced concrete structural member is reinforced, the increase in the bending bearing capacity of its normal section shall not exceed 40%, and its shear bearing capacity shall be checked. Avoid the increase in the flexural bearing capacity, which leads to the shear failure of the member before the flexural failure.