DOT has the characteristics of special section and relatively large area of excavation face. Its propulsion will cause large formation disturbance. But too much soil disturbance usually leads to a series of environmental diseases. 3D elastoplastic FDM model was applied to analysis the dynamic construction process relying on a DOT project in Shanghai. Surface displacement field and the distribution of the stress field caused by the double circle shield tunneling were calculated and analyzed. And the numerical model calculation results and field monitoring data are compared and verified comprehensively. The results show that the transverse distribution of surface deformation caused by the double circle shield construction is basically in line with the normal distribution. And the influence area is mainly concentrated in the 2 times of the width of the shield on both sides of the axis. At the time of the incision, the surface of the earth was raised, while the surface of the earth was sinking after the shield tail left. The vertical settlement of the ground surface is stabilized gradually from 20 rings. The influence of shield tunneling on the lower soil is relatively small, and the earth pressure at the bottom of the shield is the least, and the earth pressure increment is maximum in the upper part of the shield. The research results can provide some theoretical basis and prophase guidance for similar projects in the future.

LOKASI: Ruang Koleksi Umum
Rak: 2