A.5-10m B.10-15m C.15-20m D.20-25m
A.φ48㎜×3.5㎜ B.φ50㎜×3.5㎜ C.φ55㎜×4.5㎜ D.φ48㎜×2.2㎜
A.沉管成孔 B.泥漿護(hù)壁鉆孔 C.人工挖孔 D.振動沉管成孔