"Code for Construction of Concrete Structure Engineering" Article 54.Article 7: Rebar binding shall comply with the following provisions:
The lashing lap joints of the steel bars should be firmly tied with iron wires in the center and at both ends of the joints
The intersection points of each vertical surface reinforcement mesh in the reinforcement skeleton of walls, columns and beams should be fully tied;The intersection of the reinforcement mesh at the upper part of the plate should be fully tied, and the bottom reinforcement mesh can be staggered at intervals except for the edge part;
3. The stirrup hook of the beam and column and the welding joint of the welded closed stirrup should be staggered along the direction of the longitudinal stressed steel bar
The longitudinal reinforcement of the structural column should be tied synchronously with the load-bearing structure;
5. The starting distance between the stirrups in the beam and column, the horizontal distribution of steel bars in the wall, and the steel bars in the plate from the edge of the component should be 50mm.
"Code for Construction of Concrete Structure Engineering" Article 54.Explanation of Article 7:
This article specifies the detailed structure of the reinforcement binding. The reinforcement mesh of each vertical surface in the reinforcement skeleton of the wall, column and beam does not include the reinforcement mesh at the top and bottom of the beam. The edge part of the reinforcement mesh at the bottom of the plate needs to be firmly tied, and the middle part can be staggered and fastened at intervals.
The requirements for the arrangement of welded joints of stirrup hooks and welded closed stirrups are to ensure that there is no obvious weak force direction of the components. The longitudinal reinforcement of the structural column and the reinforcement of the load-bearing structure are synchronously tied, which can make the structural column and the load-bearing structure reliably connected and penetrate up and down, so as to avoid the quality and safety hazards caused by the construction of post-planting reinforcement.
During concrete pouring construction, the main stressed structures such as frame beams and columns can be poured first, and the concrete of the structural column can be poured later.
The 50mm provision in paragraph 5 is based on engineering experience, and the specific scope of application is: the position of the first stirrup at the end of the beam, the position of the first stirrup at the bottom of the column, and also includes the edge members of the dark column and the shear wall;Position of the first rebar on the side of the floor slab;The position of the first horizontal distribution of reinforcement and dark column stirrups at the bottom of the wall.
Code for the Design of Concrete Structures Article 84.2 of a kind:The longitudinal stress reinforcement of axial tension and small eccentric tension members shall not be lashed and lapped;When the steel bars in other components are tied and lapped, the diameter of the tensile steel bar should not be greater than 25mm, and the diameter of the compression steel bar should not be greater than 28mm.
Article 84.3, paragraph 3:When the parallel ribs are connected by lashing lap, they should be connected in the way of staggered lap connection of each single rib. The joint area percentage should be calculated based on all individual bars in the same connection section. The lap length of the reinforcement in the parallel reinforcement should be calculated separately according to the single reinforcement.
Code for the Design of Concrete Structures Article 84.2 Articles:
Due to the improvement of the strength of steel bars in recent years and the development of various mechanical connection technologies, the application scope and diameter restrictions of lashing lap connection steel bars are appropriately tighter than those of the original specification.
Article 84.Paragraph 3 of Article 3 provides for the following:
The overlap joint mode of dispersion and staggered reinforcement is conducive to the uniform transition of the internal force transmission of each steel bar, and improves the force transmission performance and crack state of the lap reinforcement. Therefore, the parallel reinforcement should be connected in the way of dispersion and staggered lap joint, and the lap length and joint area percentage should be calculated according to each single reinforcement in the cross-section.