动水条件下砂卵石地层深孔注浆技术探讨

Discussion on Deep Hole Grouting Technique in Sandy Cobble Stratum Under Hydrodynamic Condition

某城市轨道交通区间隧道工程,隧道拱顶埋深21.40~24.17 m,进入承压水层且地质情况复杂,地层土体以富水细砂-中砂、砂卵石为主.因地处城市核心商业区,地理位置特殊,无地面降水条件,为保证无水施工环境,须在隧道开挖施工前进行全断面深孔注浆止水.如何保证在动水条件下砂卵石地层深孔注浆的止水效果,是该工程的难点问题.结合现场施工环境,通过对注浆工艺的试验研究,得出合适的注浆参数,保证了深孔注浆的止水效果,对类似工程具有参考意义.

Taking tunnel engineering of urban rail transit as an example.the buffed depth of vault is about 21.40~24.17 m.The tunnel is in the pressurized water layer and the geological condition is complex.The soil is mainly composed of fine sand—medium sand and sandy cobble.The tunnel is located in the core business district in the city,with special geographical location and no ground rainfall conditions.In order to ensure the construction without water,the whole·section deep hole grouting was used to stop water sealing before the tunnel excavation.How to ensure the watertight effect of deep hole grouting in sandy cobble stratum under the hydrodynamic condition was the key factor for the project.Combined with the site construction environment,the paper got the appropriate grouting parameters by experimental research of grouting process,and ensured the sealing effect of deep hole grouting.Research findings could provide guidance for similar projects.