Abstract: In the construction of overlapping tunnels in waterrich strata, the ground deformation induced by stress releasing and water seepage has adverse impact on the tunnel structure and the surrounding buildings. The ground deformation rules are analyzed, with the construction of a mined overlapping tunnel of Shenzhen Metro as an example. The results show that: 1) The lower tunnel should be built before the upper tunnel, which is favorable for the stability of the tunnel structure; 2) The main causes for the ground deformation are the ground water seepage and stress releasing occurring after tunnel excavation. 

Key words: overlapping tunnel, waterrich strata, monitoring, ground deformation