Experimental study on rock mechanics characteristics of clastic reservoir with different stress paths

Abstract

At present, the development of clastic reservoir has become an important way to increase oil and gas productivity in China, and the exploitation of oil and gas will inevitably affect the mechanical properties of rocks. Therefore, it is of great significance to study the rock mechanical properties of clastic reservoir rock. In this paper, the path tests of axial pressure rising-confining pressure rising and axial pressure constant-confining pressure unloading are carried out on the clastic rock samples. The results show that the clastic rock exhibits obvious elastoplastic characteristics under the path of rising confining pressure, but has certain characteristics of elasticity and brittleness under the path of unloading confining pressure; The increase in confining pressure can effectively inhibit the expansion of the rock and increase its bearing capacity; At the same initial confining pressure, the loading failure is less severe than the unloading failure; In the unloading path, the damage of the rock sample during the deformation and failure process is higher; As the confining pressure increases, the degree of rock damage also increases.