1. Main technical content

Welded steel mesh is a kind of mesh steel products welded by a special welding machine in the factory. The longitudinal and transverse steel bars are arranged perpendicular to each other at a certain interval, and all intersections are welded by resistance spot welding. The production is automatically controlled by a computer with a multi-head spot welding machine. The mechanical properties of the steel bars before and after welding hardly change.

At present, CRB550-grade cold-rolled ribbed steel bars and HRB400-grade hot-rolled steel bars are mainly used to make welded mesh. Welded mesh projects are widely used and the technology is mature. Mainly include steel straightening and cutting technology, steel mesh production and distribution technology, mesh design and construction and installation technology.

The use of welded mesh can significantly improve the quality of steel reinforcement projects, greatly reduce on-site steel reinforcement installation man-hours, shorten the construction period, appropriately save steel, and have better comprehensive economic benefits. It is especially suitable for large-area concrete projects.

2. Technical indicators

The technical indicators of welded steel mesh should comply with "Welded Steel Mesh for Reinforced Concrete" GB/T1499. And the "Technical Specification for Reinforced Welded Mesh Concrete Structure" JGJ114. The diameter of cold-rolled ribbed steel bars should be 5-12mm, and the standard value of strength is 550N/mm2; the diameter of hot-rolled steel bars should be 6-16mm, and the standard value of yield strength should be 400N/mm2.

  The spacing of steel bars in the production direction of the welded mesh should be 100, 150, 200mm, and the spacing of the steel bars perpendicular to the production direction should be 100-400mm. The maximum length of the welded mesh should not exceed 12m, and the maximum width should not exceed 3. 3m. The shear strength of the welding joint shall not be less than 0 of the specified yield strength of the tensile steel bars of the specimen.

  3 times.

3. Scope of application

Cold rolled ribbed steel welded mesh is widely used in the reinforcement of cast-in-situ reinforced concrete structures and prefabricated components, especially for the floor slab, roof slab, floor, wall, beam and column stirrup cage and bridge deck pavement of the house And the pier anti-cracking net. Reinforcement of double-piece sleeper, track slab base and top surface paving layer of high-speed railway.

    In addition, it can be used for reinforcement of tunnel linings, water pipelines, seaports, piles, etc.

HRB400 grade steel welded mesh has better ductility, so in addition to general reinforced concrete slab structures, it is more suitable for reinforcement of components with higher seismic fortification requirements (such as the bottom reinforcement area with strong potential).

4. Typical Engineering Applied

There are a large number of various projects using welded meshes in China, and the most used areas are the Pearl River Delta, the lower Yangtze River (including Shanghai), and Beijing and Tianjin. Such as Beijing Bairong World Trade Center, Shenzhen Civic Center Project, etc.