1. The length of reinforcement at the pile head is insufficient, indicating that the anchorage length does not meet the requirements. If the diameter of reinforcement at the pile foundation is less than 25mm, lap welding can be considered to extend the anchorage length. Weld length: single-sided welding 10d, double-sided welding 5d. If the weld quality cannot be guaranteed to be qualified, it can be lengthened appropriately.

2. The lap joint of ground beam reinforcement can be welded or bound, and the joints should be staggered as far as possible. The welding lap length is the same as above. If binding lap, it depends on several factors such as concrete grade and steel bar type. If it is C30, secondary steel, the percentage of joint area is less than 50%, and the lap length is 35d* 1.2* (seismic grade correction coefficient). If it is an ordinary civil building, the seismic grade is generally Grade III, and the correction coefficient is 1.05.

(Note: This lap length algorithm is implemented according to the construction acceptance specification)