Analysis of Surface and Building Deformation by Shield Tunneling through Geology

Abstract

The research in this paper relies on the Baochang shield construction section of Jinan Metro Line R2 and uses MIDAS GTS and MIDAS GEN to construct a three-dimensional calculation model to numerically simulate the process of shield tunneling through abrupt geology. The main research focuses on surface settlement and building deformation during excavation, as well as monitoring of building deformation and surface settlement after adopting settlement control measures. The research results are as follows: The maximum settlement of tunnel excavation from hard rock to soft rock and from soft rock to hard rock occurs at the longitudinal center of the tunnel, with values of 1.66 mm and 4.82 mm. The excavation direction has a significant impact on surface deformation. The tunnel is excavated from hard rock to soft rock and the maximum deformation values in the vertical and horizontal directions of the building are 2.04 mm and 1.92 mm. After adopting settlement control measures, surface settlement and deformation of buildings were monitored. The monitoring results showed that the deformation monitoring values of the surface and buildings, after adopting engineering measurements, were lower than the values of numerical simulation. This indicates that the engineering control measures adopted can effectively constrain surface settlement and the deformation of buildings.

Research on Shield Tunneling across a River Using a Scale Model

“…A spe cial unidirectional connection of the tunnel model is set up to reduce the impact of th pre-buried tunnel on the unexcavated soil in front. When the shield traverses complex strata, it is necessary to assess the risks encountered in the project in advance and formulate a response plan [17,18]. Traditional assessment methods mainly depend on engineers' experience and computer simulation, which cannot ensure reliability [19].…”