NUMERICAL SIMULATION ANALYSIS OF DEEP FOUNDATION PIT SUPPORT FOR THE STABILITY OF ADJACENT BUILDING FOUNDATION

Deep foundation pit engineering plays an important role in urban construction. To implement deep foundation pit engineering in a densely populated city center, not only ensures the safety and stability of the foundation pit itself, but also ensures the stability of the adjacent building foundation. Taking a deep foundation pit support as an example, combined with the finite element software-Midas GTS NX,the modified-molar Coulomb constitutive model is used to establish a three-dimensional finite element model using two support forms to analyze the deep foundation pit excavation and support, including the self-supporting structure, the soil surrounding the foundation pit and the deformation law of the adjacent building foundation. The results show:(1)During the excavation of the foundation pit, the two types of support forms has little difference to the adjacent building's raft foundation, but there are significant differences in the internal forces of the two supporting structures. (2)The maximum surface settlement during the excavation of the foundation pit is not at the edge of the foundation pit, but occurs at a position about 2m from the edge of the pit. (3)The surface settlement during foundation excavation is approximately linear with the distance from the edge of the foundation pit.