Nowadays the problem of soil loss during construction of shield driving has attracted much attention, especially in sandy silt. Moreover, it is easy to cause ground subsidence and destruction of surrounding environment because of the soil’s sensitivity and disturbing characteristic. Factually, existing tunnel has high control standards for deformation as well as its deformation occurs easily when shield tunnel overpasses it at short distance, so it has always been valued the highest risk. This article will take Xuzhou Metro Line 3 first-stage project as the background and it adopt numerical method to consider the whole process of tunneling construction, including the effect of external pressures of segment. On the one hand, the evolution mechanism of soil displacement field and the responses on displacement and stress of the existing tunnel under various loads will be studied during the construction of shield tunnel overpassing existing tunnel. On the other hand, the optimal reinforcement scheme will be explored according to the different responses of the vault, the haunch and the arch bottom of the tunnel. And the validity of reinforcement design parameters combined with sandy silt’s characteristics will be researched furtherly. As a result, the paper can provide the theoretical basis for the similar project design and construction of subway tunnel overlapping tunnel.

LOKASI: Ruang Koleksi Umum
Rak: 2