Reinforcing mesh is a mesh made of longitudinal and transverse reinforcement crossed by tying or welding, which is one of the contents of “10 new technologies to be promoted and applied in the construction industry in 2005” by the Ministry of Construction.
Theoretical weight of rebar mesh (KG) = length of rebar used in rebar mesh (M) * wire diameter (MM) * wire diameter (MM) * 0.00617 (φ10 rebar 0.616539kg/m)
Reinforcing mesh is used in industrial and civil housing beams, columns, floors, roof covers, walls, concrete pavements, bridge decking, airport runways, tunnel linings, box culverts, quay flooring, prefabricated elements and other fields.
The welding process is automatically controlled by a computer. The welded mesh is of good quality and the mechanical properties of the bars before and after welding remain almost unchanged.
The reinforcement mesh is preferably made of CRB550 grade cold rolled ribbed steel bars or HRB400 grade hot rolled ribbed steel bars, or CPB550 grade cold-drawn smooth-faced steel bars.
Rebar mesh can be classified according to the raw material: cold rolled ribbed steel mesh, cold drawn round steel mesh and hot rolled ribbed steel mesh, of which cold rolled ribbed steel mesh is the most widely used. According to the grade, diameter, length and spacing of the reinforcing bars, there are two types of reinforcing bars: custom-made reinforcing bars and fixed reinforcing bars.
Reinforcing mesh series: welded steel mesh, welded construction mesh, ribbed welded mesh, welded coal mine mesh, welded coal mine mesh, welded stainless steel mesh, decorative mesh, ribbed reinforcement, hoop bars, brick belt mesh, welded wire mesh, geothermal mesh, etc.
Significantly improve the quality of reinforcement work
Significantly increase the speed of construction
Increased crack resistance of concrete
Have better overall economic benefits
1、The application of reinforcement mesh in highway cement concrete pavement project
The minimum diameter and maximum spacing of reinforcing steel mesh for reinforced concrete pavement shall conform to the provisions of the current industry standard “Design Specification for Highway Cement Concrete Pavement” JTG D40. When using cold-rolled ribbed reinforcement, the diameter of the reinforcement should not be less than 8mm, the spacing of longitudinal reinforcement should not be greater than 200mm, and the spacing of transverse reinforcement should not be greater than 300mm. the longitudinal and transverse reinforcement of the welded mesh should be of the same diameter, and the protective layer thickness of the reinforcement should not be less than 50mm. the welded mesh for reinforced concrete pavement reinforcement can be executed according to the relevant provisions of the welded mesh for reinforced concrete pavement.
(1), concrete pavement and fixed structures connected to the expansion joint can not be set up when the transmission bar, can be adjacent to the structure within the end of the plate configuration of double reinforcement network; or in the length of about 6 a 10 times the plate thickness of the range gradually increase the plate thickness by 20%.
(2), concrete pavement and bridge connection, the bridge head with a lap plate, should be set in the lap plate and concrete surface plate between the length of 6 a 10mm reinforced concrete surface transition plate. When the bridge is diagonally intersected, the reinforced concrete slab should be reinforced with reinforcement mesh at the sharp corners.
(3), concrete surface layer under the box-shaped structure lateral crossing, its top surface to the bottom surface of the distance of less than 400mm or embedded in the grass-roots level, in the top width of the structure and both sides, the concrete surface layer should be laid within a double layer of reinforcement mesh, the upper and lower layer of reinforcement mesh each from the top surface and bottom surface 1/4 a 1/3 thickness.
Concrete surface layer under a circular tubular structure lateral crossing, its top surface to the bottom surface of the distance of less than 1200mm, in both sides of the structure, the concrete surface layer should be laid within a single layer of reinforcing steel network, reinforcing steel network is located at 1/4 a 1/3 thickness from the top surface of the surface layer.
From the industry standard “Design specification for cement concrete pavement of highway” JTG D40-2002
2、The application of reinforcement mesh in bridge engineering
Mainly used in municipal bridges and highway bridge deck pavement, old bridge deck renovation, bridge pier anti-cracking, etc.. Through the domestic application of thousands of bridges project quality acceptance shows that the use of welded wire mesh significantly improve the quality of the bridge deck pavement layer, the protection layer thickness pass rate of 97% or more, the bridge deck flatness improved, almost no cracks in the bridge deck, pavement speed increased by more than 50%, reduce the cost of bridge deck pavement project about 10%. The reinforcement mesh for the bridge deck paving layer should be welded or prefabricated cold-rolled ribbed reinforcement mesh, not tied reinforcement mesh. The diameter and spacing of the reinforcement mesh for bridge deck paving should be determined according to the structural form of the bridge and the load level. The spacing of the reinforcement mesh can be 100-200mm, its diameter should be 6-l00mm. longitudinal and transverse reinforcement mesh should be used with equal spacing, welded mesh from the top surface of the protective layer thickness should not be less than 20mm.
3. The application of reinforcing steel mesh in tunnel lining
According to the national standard “highway tunnel design specification” JTGD70-2004 provisions.
In the shotcrete should be provided with ribbed reinforcement mesh, which is conducive to improving the shear and bending strength of shotcrete, improving the punching and cutting resistance of concrete, bending resistance, improving the integrity of sprayed concrete, reducing the shrinkage cracks of sprayed concrete, and preventing the local falling blocks. The reinforcement mesh should be arranged in a rectangular shape with a reinforcement spacing of 150 to 300 mm. 150 mm x 150 mm, 200 mm x 200 mm, 200 mm x 250 mm, 250 mm x 300 mm, 300 mm x 300 mm can be used in combination. The lap length of the reinforcement mesh should not be less than 30d (d is the diameter of the reinforcement).
The thickness of the protective layer of shotcrete of the reinforcement mesh shall not be less than 20mm. When a double layer of reinforcement mesh is used, the distance between the two layers of reinforcement mesh shall not be less than 60mm.
