The results show that vertical stress is equal to overburden stress at shallow level. Maximum principal stress is sub horizontal stress in the NE direction.
结果表明：显德汪煤矿垂直应力近似等于上覆岩层的自重应力，最大主应力为北东方向，且为近水平压应力。
2
The beginning of crack is vertical along the orientation of maximum horizontal principal stress.
初裂缝是沿着最大水平主应力方向的垂直缝。
3
Reinforcement type and steel plate type are the two principal forms of the vertical shearing joints of the underground diaphragm Wells by casting in place.