The underground structure construction of car-dumper shed is long and complicated.It will be some problems by layered and zoned construction with post-casting zone,such as dense steel in the zone,difficult for worker entering and ensuring construction quality etc.We replace part of the post-casting zone with the expansion reinforcing zone,and pour the concrete as the original construction sections at the same time.The technology is combining the expansion reinforcing zone and the post-casting zone as a whole.The concrete out the zone is compensating shrinkage,and the concrete in the expansion reinforcing zone and post-casting zone is filling compensation shrinkage concrete.It can solve the problem about anti-crack and anti-leakage of concrete,reduce the construction time,and bring better economy benefit.