地铁深基坑工程抗突涌准幕灌浆技术研究

杭州某地铁深基坑工程由于地连墙在圆砾层中成槽困难，使得地下连续墙（以下简称“地连墙”）插入深度减小，不能满足承压水抗突涌稳定性要求，基于此，依托该地铁深基坑实例，通过现场灌浆对比试验，确定帷幕灌浆参数，并按此参数设置帷幕灌浆，填充地连墙未隔断的圆砾层，与地连墙搭接形成封闭的阻水帷幕，解决承压水抗突涌问题。研究表明：圆砾层的孔隙度大、渗透性好，可进行灌浆处理；帷幕灌浆能够节省工期，节约造价，有效地解决圆砾层的承压水抗突涌问题。

Study on Curtain Grouting Technology for Preventing Water Gushing in Works of Metro Deep Foundation Pit

Some difficulties occurred in trough work in the round gravel layer for metro deep foundation pit with floor- wall transition make the floor-wall insert depth reduced, therefore it can not meet the requirements on the stability under the pressure of water gushing. Based on these and by taking a metro deep fbundation pit as an instance, curtain grouting parameters are determined after the cornparison tests on the field grouting. The parameter is set to guide curtain grouting, fill the floor-wall no- separated gravel layer, and to form a closed water-blocking curtain of the floor-wall overlap to solve the problems occurred in pressure water to stop water gushing. The study shows that the satisfactory round gravel porosity and permeability help grouting treatment; and curtain grouting shortens construction duration with less cost, effectively providing gravel layers some solutions on pressure water preventing-gushing issues.