|
|
|
| Stability analysis of slurry shield excavation face of Yellow River Tunnel in Jinan |
| SHI Zongtao
|
| China Railway 14th Bureau Group Co., Ltd., Jinan 250101, Shandong, China |
|
|
|
|
Abstract In order to study the stability of excavation face of Jinan Yellow River Tunnel with large diameter slurry balance shield passing through permeable sand layer, a three-dimensional calculation model was established according to the relevant parameters of typical nodes of the project. Combined with the fluid-soild coupling theory, the variation of water seepage, pore water pressure distribution, soil displacement and soil stress under different slurry pressure were analyzed. The results showed that the displacement of the excavation face changed suddenly in the process of the slurry pressure reducing. The excavation face was actively damaged, the displacement expanded upward, and the instability form conformed to the wedge model. Due to the effect of soil arch, the horizontal stress of the soil increased. In the process of slurry pressure decreasing, the height of soil arch area expanded to the surface. According to the analysis of the displacement and stress state of the soil on the excavation face, the lower limit of the slurry pressure to maintain the stability of the excavation face was 0.34 times of the water and soil pressure. It was consistent with the existing test results, which was larger than that without considering the fluid-solid coupling.
|
|
Received: 10 December 2021
Published: 20 March 2022
|
|
|
|
|
|
|
|
