单项选择题
A.少扰动、早支撑、晚撤换、快衬砌 B.少扰动、早支撑、快撤换、多衬砌 C.少扰动、早支撑、慎撤换、快衬砌 D.少扰动、早支撑、慎撤换、多衬砌
A.孔径允许偏差±10mm B.孔距允许偏差±100mm C.成孔倾角允许偏差±0.5% D.孔深允许偏差±100mm
A.5~15m B.15~30m C.30~50m D.5~25m