Experimental Study to Design an Analog Material for Jinping Marble with High Strength, High Brittleness and High Unit Weight and Ductility

The rockburst and spalling problems encountered in the Jinping Underground Laboratory are to be investigated using 3-D physical model testing. New similarity relationships for the brittleness, brittle–ductile transition and ductility characteristics of deep hard rock are first established based on the characteristics of the deep rock mass, thereby providing guidance for the development of analog materials with new characteristics that are appropriate for investigating deep rock engineering disasters via large-scale 3-D physical model tests. Achieving similarity simultaneously among the multiple physical–mechanical properties of deep hard rock constitutes the major challenge of research on analog materials. Consequently, a new method for designing analog materials by controlling the aggregate characteristics is proposed. The test results indicate that the aggregates of the analog materials can be controlled to achieve properties that are similar to those of the original rock. The newly developed analog material exhibits basic mechanical parameters and properties that are similar to those of Jinping marble, including high strength, high brittleness, and high unit weight in addition to brittle–ductile transition and ductility characteristics and deformation and failure modes. The new analog material successfully simulates the major physical–mechanical properties of Jinping marble and overcomes the limitations of preexisting methods, which develop analog materials via cementing agents, in which the achievement of similarity simultaneously among multiple properties is impossible.