幸福河南站防渗墙与灌注桩施工时序优化OA

To investigate the stress distribution characteristics and displacement evolution of the concrete cutoff walls and bored piles in the pump room of Xingfu River South Station,where the soil exhibits insufficient strength and poor seepage stability.This study optimized the coordinated construction sequence of the walls and piles to mitigate the mutual disturbance effects caused by overlapping operations.A three-dimensional numerical model was established using the geotechnical finite element software Midas GTS,enabling systematic simulation of the stress distribution and displacement evolution of the concrete cutoff walls and bored piles under different construction sequences.Under the"wall-first,pile-later"scheme,the maximum tensile stress in the cutoff wall was 0.26 MPa(well below the design value of 1.27MPa),and the displacement at the wall top was 15 mm(less than the code limit of 20 mm),indicating that the structural stability meets the requirements.In contrast,under the"pile-first,wall-later"scheme,the maximum tensile stress in the bored reached 2.14 MPa(49.7%above the design value),and the pile displacement was 32 mm(approaching the critical limit),indicating insufficient safety margin.The study indicated that adopting the"cutoff wall first,bored pile later"construction sequence could effectively control foundation stress and deformation,which was more favorable for project safety.The findings can serve as a reference for similar foundation treatment projects.