3.1.2 The quality, position and number of joints in the same section of the control key reinforcement connection joints shall comply with the relevant specifications, procedures and basic provisions; The spacing of horizontal reinforcement, stirrup spacing and stirrup densification zone must meet the requirements of design and relevant specifications, procedures and basic regulations; The binding wire of reinforcement shall be inward to avoid exposed rust; The wall column shall be added with positioning T-shaped reinforcement to ensure the thickness of reinforcement cover.
And ensure that the screw threads of the reinforcement and the connecting sleeve are clean and intact.
Operation is not allowed when the power supply voltage drops more than 5%.
2.3.3 The quality requirement is that the lap length of single side welding is 10d, and that of double side welding is 5d; The effective thickness of the weld shall not be less than 30% of the diameter of the main reinforcement, and the width of the weld shall not be less than 80% of the diameter of the main reinforcement; The welds shall be uniform and full without air holes.
3.2 Structural beam reinforcement 3.2.1 Process flow: stirrup spacing positioning – setting beam stirrup – passing through the bottom longitudinal bar of main beam – passing through the bottom longitudinal bar of secondary beam – passing through the upper longitudinal bar of main beam – binding according to the stirrup spacing – passing through the upper longitudinal bar of secondary beam – setting beam bottom cushion block – inspection..
The reinforcement shall be screwed into the sleeve in accordance with the axis, and the sleeve shall be tightened with a special pipe wrench, so that the two screw heads are mutually tightened at the center of the sleeve.
Before use, it shall be dried.
Originated from | Arrangement of China Construction Third Engineering Bureau and Baidu Library | Section I Reinforcement Works of Douding Construction 1.
When the reinforcement with different diameters is welded, the upper and lower reinforcements shall be on the same axis.
Reinforcement installation 3.1 Wall column reinforcement 3.1.1 Process flow: setting out – reinforcement positioning – stirrup set – vertical reinforcement connection – column stirrup binding – horizontal reinforcement binding – hook hanging – cushion block setting – correction.
The distance from the bending point to the end of the reinforcement joint shall not be less than 10 times of the reinforcement diameter.
The tightening torque value shall comply with the general technical specification for mechanical connection of reinforcement.
3.
The welding flux shall be stored in a dry warehouse to prevent dampness.
Welders shall hold valid work licenses and wear necessary articles such as welding shoes and gloves before welding.
When the ambient temperature is lower than – 20 °, welding is not suitable.
After the joint is welded, it should be stopped for 20~30s (when welding in cold areas, the stop time should be extended appropriately) before the welding flux can be recovered and the welding fixture can be removed.
2.1.3 The quality requirement is that each end of the sleeve shall not have more than one complete thread exposed.
When it is recycled repeatedly, the slag and sundries shall be removed, and it shall be mixed with the new welding flux before use.
Reinforcement processing 1.1 Process flow: reinforcement blanking calculation – reinforcement mobilization acceptance – reinforcement straightening and cutting – reinforcement welding – reinforcement cold bending 1.2 Control points 1.2.1 Hook method For general structural members, the bending angle of the stirrup hook should not be less than 90 °, and the length of the straight section after bending should not be less than 5 times of the reinforcement diameter; For structural members with seismic fortification requirements or special design requirements, the bending angle of stirrup hook shall not be less than 135 °, and the length of straight section after bending shall not be less than 10 times of stirrup diameter and the larger value of 75mm.
for processing the reinforcement thread must be consistent with the thread shape and thread pitch of the connecting sleeve, and they must be inspected as qualified by the matching gauge; 10% of the processing batches of each specification shall be randomly sampled for the qualified steel wire heads through self inspection, and no less than 10 shall be sampled; Put a plastic protective sleeve on the thread processed at the end of the reinforcement to avoid damage to the thread or contamination by dirt.
When welding is necessary, effective shielding measures should be taken.
The qualified joints shall be identified.
2.3 Arc welding connection 2.3.1 Process flow: check equipment – select welding parameters – test welding – determine welding parameters – welding – quality inspection.
1.3 Quality requirements The allowable deviation of the reinforcement after bending and forming is: full length ± 10mm; The starting point displacement of bent reinforcement is 20mm; Inside diameter of stirrup ± 3mm 2.
After welding, it is strictly prohibited to smash the reinforcement joints, and water the newly welded streets to promote cooling.
1.2.2 Before threading the straight thread processing reinforcement, the end shall be cut flat with a toothless saw and shall not be inclined or bent; The thread head, thread shape, thread pitch, etc.
2.1.2 When connecting reinforcement with control points, the specification of reinforcement and sleeve shall be consistent, and the type, pitch and outer diameter of reinforcement thread shall match the sleeve.
Rain, snow and wind above level 6 (including level 6) should not be used for open air welding.
If there are no specific requirements in the design, it shall not be greater than 50% in the tensile zone; The joint shall not be in the stirrup densification area.
In the same connection section, the joint rate of longitudinal load-bearing reinforcement shall meet the design requirements.
The power supply shall meet the requirements.
2.2 Electroslag pressure welding connection 2.2.1 Selection of welding parameters in the process flow → installation of clamps and reinforcement → placement of arc strike wire balls → placement of welding boxes and filling of welding flux → trial welding → determination of welding parameters → welding → recovery of welding flux → removal of clamps → quality inspection 2.2.2 The cutting length of the grade diameter of the reinforcement in the control points must meet the requirements of the material table, the end should be straight without horseshoe bending, bending, twisting and deformation, the end should be 200mm free of corrosion, and the concrete slurry.
Reinforcement connection 2.1 Straight thread connection 2.1.1 Process flow: reinforcement blanking – reinforcement head processing – reinforcement head inspection – reinforcement connection – reinforcement connection joint inspection.
2.3.2 During overlap welding of control points, the reinforcement at the welding end should be pre bent, and the diameters of the two reinforcements should be on the same line; After welding, the surface welding slag shall be cleaned timely.
The joints that are not cooled after welding should avoid rain and snow.
2.2.3 The quality requirement is that the welding package shall be uniform, and the thickness of the welding package shall not be less than 4mm when the diameter of the reinforcement is 25mm and below, and shall not be less than 6mm when the diameter of the reinforcement is 28mm and above; The contact between reinforcement and electrode shall be free of burn defect; The bending angle at the joint shall not be greater than 2 °; The axis offset at the joint shall not be greater than 1mm.
