岩石の破壊および降伏条件
新方式の三軸試験法による研究
1971 年 20 巻 209 号 p. 143-150
詳細
1971 年 20 巻 209 号 p. 143-150
A new triaxial compression technique has made it possible to make studies on laws of fracture and yielding of rocks under general triaxial stress states, in which all the three principal stresses are different. By this new method, the effects of the stress states to fracture and yielding of rocks were experimentally studied.
Fracture and flow properties of rocks are markedly affected not only by the least compression σ3, but also by the intermediate compression σ2. The stress states, which produce fracture and yielding, are determined by the following formulas:
τoct=f1(σ1+σ3) for fracture,
τoct=f2(σ1+σ2+σ3) for yielding,
where f1 and f2 are functions of monotonic increase. The failure criteria, corresponding to von Mises' criteria generalized, are physically interpreted as follows: fracture or yielding will occur when the distorsional strain energy reaches a critical value which increases monotonically with the effective mean pressure: (σ1+σ3)/2 for fracture and (σ1+σ2+σ3)/3 for yielding.
