Study on the Shear Strength Index of Rock Mass Based on the Rock Mechanics Backpack Experimental System

Overseas survey projects are subject to many restrictions by the host countries. Many countries lack laboratories, or their testing standards differ substantially from those in China, which is a crucial factor affecting the implementation of overseas projects. To obtain rock mass mechanical parameters for a mine overseas, indoor rock tests are conducted at a mine in Central Asia using a rock mechanics backpack experimental system in accordance with relevant domestic specifications. Independent tests are carried out on rocks from different regions and with different lithologies to obtain raw data including rock density, rock uniaxial compressive strength (natural and saturated), and rock triaxial compressive strength (natural and saturated). The Hoek-Brown failure criterion is applied to reduce rock mass parameters and obtain rock mass shear strength indices. Finally, an inversion analysis is performed on the landslide body to determine rock mass shear strength indices, which are then compared with the experimentally obtained indices. The results show that the error between the obtained rock mass shear strength indices and the inversion-derived rock mass shear strength indices is within 3%, verifying the feasibility of using the backpack experimental system to obtain rock mass shear strength indices. This study has reference value for similar projects.