浅埋地铁车站基坑防渗墙支护体系稳定性分析
作者简介:
伦冠栋,工程师,硕士,E⁃mail: lunguandong@ 163. com
作者单位:
中铁十八局集团第三工程有限公司,河北涿州 072750
基金项目:
∗中国铁建股份有限公司 2022 年度科技研究开发计划( 2022⁃C1);中铁十八局集团有限公司 2022 年度科研创新项目(C2022⁃051)
摘要:
针对浅埋地铁车站建设需求,提出采用防渗墙结合明挖法的施工方案,该方案在位移控制要求严格的工程场景中具有显著优势。以济南地铁 4 号线浆水泉路站为例,车站净长 248.7m,标准段净宽为 20.2m,具有浅埋(地下水位偏高)、软土地层、大跨度结构设计等典型特征。针对特殊地质条件引发的支护体系稳定性与地表变形控制难题,研究采用有限元法对施工全过程进行数值模拟及地层响应分析。首先通过工法比较选择确定防渗墙⁃中间隔墙⁃结构楼板协同支护体系,继而优化各构件的几何参数(防渗墙嵌入深度、墙厚度、板厚度)。数值模拟结果表明:开挖过程中地表沉降曲线呈典型凹槽形态,最大沉降值 18.2mm 出现在防渗墙附近区域,该分布规律与现场监测数据吻合。

English:
A construction scheme of a anti⁃seepage wall combined with an open⁃cut method is proposed,aiming at the construction demand of shallow buried subway stations. This scheme has significantadvantages in engineering scenarios with strict displacement control requirements. The JiangshuiquanRoad Station of Jinan Metro Line 4,with a net length of 248.7meters and a net width of the standardsection of 20.2meters,was taken as an example. It has typical characteristics such as shallow burial(high groundwater level), soft soil layer, and large⁃span structure design. Aiming at the problem ofsupporting system stability and surface deformation control caused by special geological conditions, thefinite element method was adopted to simulate the whole construction process and analyze the formationresponse. Firstly, the collaborative support system of anti⁃seepage wall⁃intermediate partition wall⁃structure floor was determined by comparison of construction methods, and then the geometric parametersof each component ( embedded depth of anti⁃seepage wall,wall thickness, and plate thickness)wereoptimized. The numerical simulation results indicate that the surface settlement curve shows a typicalgroove shape during the excavation process, and the maximum settlement value of 18.2mm appears in thearea near the wall. The distribution law is consistent with the field monitoring data.