The wide and rapid popularization and application of cold drawn ribbed steel bars and hot rolled grade III steel bars in Dalian provide a good material basis for the development of welded mesh. The formal implementation of welding net product standard and use rules has played a positive role in improving product quality and accelerating promotion and application.
Under the concrete surface, there is a box structure crossing transversely. When the distance from the top to the bottom of the surface is less than 400mm or embedded in the base course, the double-layer reinforced welded mesh shall be set in the concrete surface, and each of the upper and lower reinforced welded mesh shall be 1 / 4-1 / 3 thick from the top and bottom of the surface. The grid of welded steel mesh shall be arranged in rectangle, and the spacing between the steel bars of welded steel mesh shall be 150-300 mm.
The combination of 150 mm × 150 mm, 200 mm × 200 mm, 200 mm × 250 mm, 250 mm × 300 mm and 300 mm × 300 mm can be adopted. The overlapping length of welded steel mesh shall not be less than 30d (D is the diameter of steel bar). The shape and size of the customized welding network shall be determined by the supplier and the demander through consultation according to the design and construction requirements and the specific project conditions.
The longitudinal and transverse reinforcement of the welded mesh should be of the same diameter, and the thickness of the protective layer of the reinforcement should not be less than 50 mm. The welded mesh used for reinforcement of the reinforced concrete pavement can be implemented according to the relevant provisions of the welded mesh used for the reinforced concrete pavement. When the two meshes are overlapped, the center and both ends of the overlapping area shall be bound firmly with iron wire, and the overlapping method, buckle method or flat method shall be adopted for the overlapping of the reinforcement meshes to meet the requirements.
Production capacity of welded steel fabric. When the longitudinal and transverse reinforcement of the welded mesh are single reinforcement, the nominal diameter of the thinner reinforcement shall not be less than 0.6 times of the nominal diameter of the thicker reinforcement, that is, Dmin ≥ 0.6damx. The shear resistance (unit: n) of the welded joint of the welded mesh shall not be less than the product of 150 and the nominal cross-sectional area (unit: mm2) of the coarser reinforcement.