The pile foundation steel bar processing entire process, the steel bar work must know（二）!

The finished steel bar must be lifted and lowered gently to avoid the deformation caused by the fall. The finished products after the inspection of specifications and dimensions shall be bolted with the material label according to the number; According to the name of the project, location and steel bar number, according to the order of use, to prevent the first used under pressure.

1) the steel bar cage is mainly made in the steel bar processing field. When the pile grows to 20m, it is processed in 2-3 sections to avoid the hoisting deformation of the steel bar cage. Un-stiffened stirrup binding is used to connect with the main steel bar of connection, in order to strengthen the overall form of reinforcing cage, in the proper place to spot welding (welding shall be carried out according to the requirements of the laboratory before sampling test), strengthen the stirrup used tower welding construction according to the size of design drawings (stirrup position according to the design drawing set, cannot be changed without permission).

2) the steel cage of pile foundation is mainly made in the steel bar processing field, and the longitudinal main bar is welded on both sides. The welding axis deviation of the whole steel cage length is no more than 10mm (refer to the axis deviation of the whole pile). Reinforcing stirrup adopts lap welding according to the design drawing size construction. The electrode used must be qualified material (the electrode shall be welded with the qualified electrode identified by the supervising engineer). The welded or bound joints of the stressed steel bar shall be set in a place with less internal force and staggered arrangement. For welded joints, within the joint length range (within the range of 35d length, that is 980mm, but not less than 500mm, and d is the diameter of reinforcement), there shall be no two joints for the same reinforcement. The section area of the joint is not more than 50% of the total section area.

3) relevant regulations for welding steel bars

(1) welding welding test must be conducted before, until they have passed the test of formal welding, steel welding, steel welded parts shall be removed and contact with the electrodes on the surface of the steel rusty spot oil pollution, sundry etc, reinforced the end if there is bent, and twisted, must be paid to the straightening or removed.

(2) the welded steel bars in the same working class shall be one batch, and 10% of the joints in each batch shall be drawn for appearance inspection, but not less than 10 pieces. The inspection results shall meet the acceptance standards.

(3) there shall be no transverse crack at the joint and no bending greater than 4 degrees.

(4) the steel axis deviation at the joint shall not be greater than 2mm.

(5) during lap welding, the steel bar at the welding end should be pre-bent and the axis of the two steel bars should be in the same line; Two points should be fixed for lap welding. The distance between the positioning weld and the lap end should be greater than or equal to 20mm. When welding, the arc shall be ignited in the weld formed by lap welding, and the arc pit shall be filled before the end end end arc re-arcing, and the main weld shall be fused with the beginning and end of the initial seam of the locating weld. The weld thickness of lap welding shall not be less than 0.3 times of the diameter of the main rib, i.e., it shall not be less than 8.4mm, and the weld width shall not be less than 0.7 times of the diameter of the main rib and shall not be less than 8mm.

4) relevant regulations on site binding of steel bars

(1) steel wire binding should be applied to strengthen the intersection of steel bars. If necessary, the overall shape of steel bar can also be strengthened by spot welding.