A NEW ANALYSIS ON GROUND PRESSURES AROUND OPENINGS
圆形巷道围岩变形压力新解法

The strength of failing rockmass on its stress-strain curve is regarded as a plastic soft strength and a general solution is put forward to analyze the radius and stresses of the plastic zone around a circle tunnel. The surrounding rock of tunnel is considered as a kind of strength softening mass as its strain developing. The general solution is also suitable for analysis of the ground pressure around openings in the rockmass characterized by ideal elasto-plastic, strength-softening and strength-hardening behaviour. Therefore,the results could be applied into practical tunnel engineerings. The famous H. Kastner formula is one of the special solutions in this paper under the condition of the ideal elasto-plastic model.