ANALYSIS ON THE MECHANICS AND DEFORMATION OF SIDE PILE STRUCTURE IN METRO STATION WITH THE PBA METHOD

There is limited research on the interaction mechanism between the buckling load of the side pile top and the soil pressure behind pile (SPP) with the side pile. As the side pile serves as a crucial component of the lining structure in the metro, using the pile -beam -arch (PBA) method, it plays a vital role in maintaining the mechanical stability and deformation control of the station's lining system. Based on the Guangzhou Metro Line 11 project, this paper delves into the impact of mechanical characteristics and deformation of the side pile using the PBA method. It considers various factors such as different buckling loads, including horizontal load of arch (HLA), vertical load of arch (VLA) and SPP and offers corresponding construction suggestions. Our findings indicate that the lateral displacement and deformation of the side pile are primarily influenced by the HLA. The optimal HLA value stands at 1200kN. As the HLA increases, the side pile undergoes a transformation from a forward -inclined deformation mode to a belly distension deformation mode when moving towards the station's interior. The influence of HLA on bending moments about the side pile surpasses that of axial force. The VLA exerts a more significant effect on vertical settlement of the side pile, yet its impact on lateral pile body deformation is minimal. An increase in HLA significantly impacts the axial force of the side pile, but has minimal effects on bending moments. The SPP holds significant influence on the stability of the side pile; hence, it is recommended to implement appropriate lining measures to guarantee stability when dealing with exceptionally high SPP values.