Numerical Simulation Analysis of Segmental Excavation Method for Deep Well Pit

In order to study the change of shear stress and plastic zone in the construction of deep foundation pit with large "aspect ratio" using segmental sequential excavation, the article relies on the Jiangxinzhou intermediate air shaft foundation pit project, and simulates the excavation process of the foundation pit by using FLAC3D software to analyze the effect of segmental sequential excavation on the construction process of the large "aspect ratio" deep well foundation pit. aspect ratio" deep well pit construction process. The results show that: the maximum shear strain of the foundation pit mainly occurs in the "proximity" edge surface inside the foundation pit; after the simulation of the foundation pit excavation process is finished, the existing shear damage zone inside the foundation pit mainly exists at the joints between the edge of the excavation pit and the ground wall, and the existing tensile damage zone mainly exists at the proximity edge of the excavation pit; there are fewer plastic zones around the diaphragm wall. The plastic zone is less. When using segmental sequential excavation method for foundation pit construction, special attention should be paid to the critical edge surface inside the foundation pit to avoid collapse hazards; at the same time, diaphragm wall can effectively avoid the collapse of the soil layer outside the foundation pit, and it should be used as much as possible under the circumstance of controlling the cost.