Hotel underground parking garage renovation project: finite element analysis of deep excavation induced effects

The soil disturbance caused by deep excavation of adjacent buildings will have adverse effects on building foundation. This will threaten the stability of superstructure and engineering safety. In this paper, a three-dimensional finite element model is established by taking the renovation project of underground parking garage near a hotel as an example. The calculated results of the model agree well with the measured data, which verifies the validity of the model. On this basis, the construction mechanical behavior of deep excavation of adjacent buildings is studied. The research content mainly includes the stress and deformation characteristics of soil and structural members. The results show that the stress and deformation characteristics of soil and structural members are sensitive to the excavation depth of deep excavation. It increases with the increase of excavation depth. The vertical displacement of soil at the bottom of deep excavation is mainly uplift. When the excavation is completed, the maximum uplift value is 26.9 mm. The displacement of strip foundation is mainly settlement. The maximum vertical displacement of the foundation of buildings A and B is − 5.2 mm and − 10.98 mm, respectively. In general, the vertical displacement of column foot shows the deformation law of “slope”. The maximum displacements of diaphragm wall 1 and 2 are 6.09 mm and − 6.56 mm respectively. The maximum values of XX direction stress and YY direction bending moment are − 494.2 kN/m and − 746.1 kN m/m, respectively. The axial force of the internal support is mainly pressure. The maximum value is − 1225.9 kN. The total maximum axial force shows a trend of “increasing”. When the excavation is completed, the total maximum axial force is − 2748.3 kN. The deformation and internal force distribution of soil and structural members at the bottom of deep excavation have obvious spatial characteristics. The closer to the center of the deep excavation, the greater the value. Therefore, attention should be focused and necessary measures should be taken.