暗挖地铁车站穿越软弱地层注浆设计优化研究

Research on grouting design optimization of underground metro station crossing through weak strata

基于多孔介质流固耦合原理,考虑岩土体压缩性、孔隙率、渗透率以及体积应变等因素,研究富水断层破碎带地层注浆加固前后,围岩与加固圈的塑性区分布、拱顶沉降以及渗水量的变化规律。研究发现,变形量和渗水量随着注浆加固圈厚度增加而减少,当加固圈厚度达到一定值后减少量趋缓,据此确定地铁车站注浆加固圈的合理厚度为5~6 m。研究成果成功应用于青岛地铁某暗挖车站注浆工程中,通过对比现场实测数据,验证了注浆设计以及数值模拟的可靠性。

Based on the principle of fluid-solid coupling in porous media and considering the factors like compressibility,porosity,permeability and volume strain of soil,this paper analyzed the changing principle of the plastic zone distribution of surrounding rock and reinforcement ring,the settlement of arch crown and the water permeability before and after grouting reinforcement in the strata of water rich fault fractured zone.It was found that the amount of deformation and seepage decreases with the increase of grouting reinforcement circle’s thickness.When the thickness of reinforcement circle reaches a certain value,the amount of reduction slows down.The reasonable thickness of grouting reinforcement circle of metro station was determined to be 5~6 m.The research results had been successfully applied in the grouting project of an underground excavation station of Qingdao Metro.The reliability of grouting design and numerical simulation had been verified by comparing with the field measured data.