石家庄地区无水砂层渗透注浆数值模拟研究

Numerical Simulation of Seepage Grouting in Anhydrous Sand in Shijiazhuang Area

石家庄地铁矿山法施工地段需要穿越大范围中粗砂和粉细砂等无水砂性地层,这类地层的土体强度低,自稳能力差,为保证隧道施工安全,限制隧道变形及地表沉降,需进行超前注浆加固。以石家庄地区中粗砂地层为研究对象,考虑浆液粘度时变性,配置不同水灰比的水泥浆液进行室内试验,测试其粘度,得到不同水灰比的水泥浆液粘度的时间变化函数,并将粘度时变函数引入到有限元软件COMSOL Multiphysics中,研究不同注浆压力、浆液粘度、介质孔隙率等参数对注浆的影响规律,优化了注浆设计参数,研究成果对于指导工程施工,具有重要借鉴意义。

The construction area of Shijiazhuang subway mining method needs to pass through the anhydrous sand strata such as coarse sand and fine sand in a large range.This kind of stratum has low strength and poor self-stability.In order to ensure the safety of tunnel construction and control the deformation around the tunnel and surface subsidence,it is necessary to carry out advance grouting reinforcement.In this paper,medium coarse sand stratum in Shijiazhuang area was taken as the research object,and the time-varying slurry viscosity was taken into consideration.Cement slurry with different water-cement ratios was used for indoor tests to test its viscosity.The time-varying function of cement slurry viscosity with different water-cement ratios was obtained,and the time-varying function of viscosity was introduced into the finite element software COMSOL Multiphysics.The influence law of different grouting pressure,slurry viscosity,medium porosity and other parameters on grouting were studied,and the grouting design parameters were optimized.The research results have important reference significance for guiding engineering construction.