1. The joint should be set at less stress place of steel bar. Two joints should not be set in a steel bar. The joints of longitudinally stressed steel bars in the same reinforcement members should be staggered from each other.

2. It is strictly forbidden to use overlapping joints diameter over 16mm steel bars, which should take welded connection or mechanical connection.

Illustrate:

1. Lap joint connection: The lap joint length should meet the design and specification requirements, and the adjacent steel bar joints should be staggered by 50%; the joint stagger height should be 1.3 times over the lap joint length.

2. Mechanical connection: the finished concrete surface of the joint should over 50cm, and the joints of adjacent steel bars should be staggered by 50%; the height of joint stagger should not be less than 35d.

3. Welding connection: the finished concrete surface of the joint should not be less than 50cm, and the adjacent steel bar joints should be staggered by 50%; the height of the joint stagger should be over35d and not less than 50cm.