富水复合地层中土压平衡盾构掘进参数控制

摘要

When earth pressure balance shield tunneling is in water rich complex strata,especially in the upper water rich sand and gravel stratum and lower mudstone formation, it is difficult for the shield tunneling parameters to control,that both can have the risk of spiral spew, and the risk of mud cakes. According to the buried depth of shield and hydrogeological conditions,through timely adjustment of the earth pressure and the use of high-quality foam polymer and the optimal combination,it can avoid spiral cutter gushing risk. Meanwhile,through adding soil flushing device for cutter and chamber to control the mud cake. Practice shows that through reasonable parameters control and necessary auxiliary equipment optimization measures,it can effectively control the ground settlement limit risk induced by spiral jet and shutter mud cake during earth pressure balance shield tunneling in water rich strata, which can assure construction safety.%土压平衡盾构在富水复合地层中掘进,尤其在上部富水砂砾地层、下部泥岩的地层中掘进,盾构掘进参数控制难度较大,既有发生螺旋机喷涌的风险,又有刀盘、土仓结泥饼的风险.根据盾构埋深与水文地质情况,及时调整土仓压力,利用优质泡沫与高分子聚合物优化组合有效规避螺旋机喷涌风险;增加刀盘、土仓冲洗装置,掘进中同步冲洗刀盘、土仓,达到泥饼防控的目的.实践证明,通过合理的参数控制并辅助必要的设备优化措施,可以有效控制土压平衡盾构在富水复合地层掘进中因螺旋机喷涌、刀盘(土仓)结泥饼引起的地面沉降超限(坍塌)风险,保证盾构施工安全.