In the shotcrete of Dalian mesh, the welding mesh of ribbed steel bar is set in it, which is beneficial to improve the shear and bending strength of shotcrete, the punching and bending resistance of concrete, the integrity of shotcrete, the shrinkage crack of shotcrete and the local falling off.
At present, the design strength of a large number of round steel bars is 210n / mm (Pinggang), while the design strength of welded steel fabric is 360n / mm (Pinggang). According to the principle of equal strength replacement, and considering the comprehensive factors, the use of welded steel fabric can save more than 30% of the use of steel bars. And the steel mesh needs to be processed after being transported to the construction site, so there is no loss. It is made by automatic and intelligent production line.
The mesh size, reinforcement specification and quality are strictly controlled. The utility model can avoid the omission of artificial binding net, and the binding part is firm. The situation of mistakes in helping and cutting materials occurs. The mesh has large rigidity, good elasticity, uniform and accurate spacing, and high strength of welding points. Therefore, the project quality is greatly improved. When the expansion joint connecting the concrete pavement and the fixed structure cannot be provided with a dowel bar.
The double-layer welded steel mesh can be arranged in the end of the slab adjacent to the structure, or the slab thickness can be increased by 20% gradually within the range of 6-10 times of the slab thickness. According to the technical specification, the welded mesh should be made of crb550 cold-rolled ribbed steel bars or crb510 cold drawn plain steel bars. A welded mesh should be welded with the same type of reinforcement.
According to the shape and specification, the welded mesh can be divided into two types: setting and customization. The spacing and diameter of the reinforcement in two directions of the shaped welded mesh can be different, but the reinforcement in the same direction should have the same diameter, spacing and length, which has been stipulated in the relevant standards and regulations. Installation of bottom net at column corner.