A.基底為堅(jiān)硬均勻的硬黏土 B.持力層明顯不均勻 C.淺部有軟弱下臥層 D.有淺埋坑穴,支接觀察難以發(fā)現(xiàn)
A.分段開(kāi)挖 B.分段支護(hù) C.一次挖就再行支護(hù) D.按設(shè)計(jì)要求進(jìn)行開(kāi)挖及支護(hù)
A.開(kāi)槽支撐 B.先挖后撐 C.分層開(kāi)挖 D.嚴(yán)禁超挖