RESEARCH ON PROGRESSIVE DAMAGE CONSTITUTIVE MODEL AND ITS APPLICATION TO DEEP ROCK

The disaster control of the deep rock is closely related to the constitutive model of the rock. Based on the failure process and failure mechanism of rock, the localized progressive damage constitutive model is developed. In this model, the representative volume element (RVE) is divided into the elastic zone and localized shear band, and the deformation process of the localized shear band is again separated into cohesion weakening and friction strengthening phases. The emphasis in establishing the model is placed on the failure essence of the rock, ie., the cohesion weakening and friction strengthening phases should be exerted in tandem. Moreover, the chain model in localized band and homogenization method are adopted to combine the meso characteristics with the macro mechanical properties in this localized progressive damage constitutive model. Furthermore, based on the experimental results of Yumlu & Ozbay, the localized progressive damage constitutive model is well validated. Finally, the localized progressive failure characteristics of the deep rock are analyzed by changing the model’s parameters. The intrinsic reasons and influence factors of “size effect”, “shape effect”, strain softening phenomena and type II stress-strain curves are pointed out.