Experimental and constitutive modeling investigations on marble in Jinping Underground Laboratory

The Jinping Underground Laboratory is the deepest and largest underground laboratory in the world, with a maximum buried depth of approximately 2400 m. The objective is to study the brittle‐ductile transition of marble through a combination of experimental research and constitutive modeling. Triaxial compression and triaxial cyclic loading tests are initially conducted to explore the accumulation of pre‐peak plastic strain and the deterioration of stiffness of the marble. Then, a specific constitutive model is developed to accurately reflect the pre‐peak plastic hardening and post‐peak strain softening behaviors based on the deformation and failure mechanism of the marble. The incremental constitutive relationship of the proposed model is subsequently derived in detail, and the model parameters are calibrated using data obtained from the test results. Finally, the effectiveness of the proposed model is assessed by comparing its results with the experimental results of the marble. The findings show that the proposed model accurately predicts the behavior of the marble, and its results are in good agreement with the test data.