Subway cross-passage excavation,Reinforcement of soft soil,Crown displacement,Cement mixing," />
Simulation Analysis of the Excavation Deformation of a Reinforced Subway Cross-Passage in Soft Soil
Abstract A case of reinforcement and excavation of a subway cross-passage in alluvial soft soil at the Pearl River Delta is studied, for which the 3D finite element model is used to simulate the excavation process under the different reinforcement options of a deep mixing pile or advance grouting condulet, and the crown displacements of the cross-passage under different options are calculated and analyzed. The results show that the deep mixing pile is highly adaptable and may strengthen the soil and control excavation deformation by different proposals, while the advance grouting condulet is incompetent. A combined application of the cement mixing pile and advance grouting condulet can efficiently reduce construction costs and ground deformation caused by the excavation of underground works in soft soil. The magnitude of deformation depends on the overall strength of the soil mass after reinforcement, and the affect of advance rate on deformation is greater compared with that of support time if the strength of the soil mass reaches a certain value, otherwise the opposite is true. For these reasons, the excavation method and procedure can be rationalized to shorten the construction time.
Abstract：
A case of reinforcement and excavation of a subway cross-passage in alluvial soft soil at the Pearl River Delta is studied, for which the 3D finite element model is used to simulate the excavation process under the different reinforcement options of a deep mixing pile or advance grouting condulet, and the crown displacements of the cross-passage under different options are calculated and analyzed. The results show that the deep mixing pile is highly adaptable and may strengthen the soil and control excavation deformation by different proposals, while the advance grouting condulet is incompetent. A combined application of the cement mixing pile and advance grouting condulet can efficiently reduce construction costs and ground deformation caused by the excavation of underground works in soft soil. The magnitude of deformation depends on the overall strength of the soil mass after reinforcement, and the affect of advance rate on deformation is greater compared with that of support time if the strength of the soil mass reaches a certain value, otherwise the opposite is true. For these reasons, the excavation method and procedure can be rationalized to shorten the construction time.
.Simulation Analysis of the Excavation Deformation of a Reinforced Subway Cross-Passage in Soft Soil[J] MODERN TUNNELLING TECHNOLOGY, 2013,V50(5): 129-134
2013, Vol. 50 