A.1.5% B.0.8% C.1.2% D.1%
A.0.15～0.4m/s B.0.25～4m/s C.0.35～4m/s
A.三心拱形 B.半圆拱形 C.梯形 D.三心拱形、半圆拱形和梯形
A.20～40min B.15～30min C.30min D.60min
A、锚网 B、锚杆 C、锚注 D、扶棚
