Self-sealability of fractures in rock and its application to fracture and strength control

对裂隙的封闭性进行了一系列的试验研究，并探讨了裂隙封闭性在岩土工程中的应用。首先，分析了环境对岩石亚临界裂纹扩展的影响，阐明了裂纹扩展的机理。其次，研究了岩石类材料在水中的裂缝自封闭过程，阐明了自封闭机理。再次，对裂缝扩展过程进行了数值分析，提出了控制裂缝扩展的设计方法，根据这些结果，提出了一种估算岩石长期强度的方法。指出岩石强度可以通过控制环境条件来控制。

A series of experimental studies on the sealability of fracture has been performed and its application to geotechnical engineering has been discussed. Firstly, analyzing the influence of environments on the sub-critical crack growth in rock, the mechanism of crack growth has been clarified. Secondarily, the self-sealing process of fracture in the rocklike material in water was investigated and the mechanism of self-sealing was clarified. Thirdly, the process of fracture propagation was analyzed numerically and a design method to control fracture propagation, i.e., crack orientation and so on. From these results, a method to estimate the long-term strength of rock has been proposed. Furthermore it is pointed out that the strength of rock can be controlled by controlling the environmental condition.