The experimental results show that the behavior of the shear compression failure mode is quite different from the diagonal tension failure mode although both shear failure modes are sudden and brittle.

This paper tells the influence on city environment of unhealthy geology tendencies caused by the under-ground acitivity in city,such as the surface subsidence,surfance sink,slope destruction and the badly affect of the groundwater and its pollution,and it also puts forward the preventive strategy.

Fuzzy cluster analysis and evaluation on coal mine shaft destruction;