Mechanical Experimental Study of Rough Fractured Rock Mass Based on Layered Pouring

To accurately study the fracture damage evolution law of deep shale, natural fracture surfaces of deep shale are obtained based on three-dimensional scanning. Using 3D modeling, 3D printing, and rock-like materials, we prepared rough fracture surfaces and rock matrices of deep shale. Further, we fabricated rock samples containing fracture surfaces with different angles and roughness through layered pouring. True triaxial compression tests were conducted to investigate the influence of different fracture angles and mechanical loading methods on the mechanical properties and failure modes of the rock samples. The experimental results indicate that: (1) Rock-like samples prepared using 3D printing technology and layered pouring can substitute deep shale for studying the collapse failure law of wellbores. (2) The influence of different fracture angles on the compressive strength of rock samples generally shows a "U" shaped trend, with the strength first decreasing and then increasing. (3) Different mechanical loading methods significantly affect the compressive strength and failure modes of rock samples. Different loading methods lead to changes in the free surface of the rock samples, thereby altering their compressive strength and failure modes. The research results can provide a reference for the preparation of rock-like samples and indoor studies.