14th World Congress in Computational Mechanics (WCCM) ECCOMAS Congress 2020 19 – 24 July 2020, Paris, France

THE SIMULATION OF ROCKFILL IN A CHARACTERISTIC OF THREE-DIMENSIONAL STRENGTH

Xuefeng Li1, Ruijie Li1,2 1 Solid Mechanics Institute, University, No. 489, Helanshan West Road, Xixia , , Ningxia, P. R. , 750021, [email protected] 2 Highway Construction Authority of Ningxia Hui Nationality Autonomous Region, No. 715, Beijing Middle Road, Jinfeng district, Yinchuan, Ningxia, P. R. China, 750011, [email protected]

Key Words: Rockfill, Three-dimensional strength characteristic, Fabric, Anisotropy, Simulation.

In order to simulate the three-dimensional strength characteristics of rockfill material under anisotropic state, it introduced the anisotropic state variable into the Mohr-Coulomb failure criterion, and obtained the failure criterion describing the three-dimensional strength of rockfill in exponential form in this paper. Based on the consideration of the fabric of original rockfill particles, the anisotropic state variables were established. The strength and test characteristics were simulated by the consolidation drainage triaxial shear test. The results shown that (1) The fractal theory can be used to quantitatively describe the rockfill particles crushing with all kinds of grades under different stress levels. The test results also indicated that the rockfill particles crushing degree increased as the confining pressure and the fine gradation of the initial rockfill materials increased. (2) The critical state line of rockfill was unique on the qp−  surface, and its critical state experimental points shown a linear change trend. (3) The fabric of rockfill particles was closely related to the three-dimensional strength characteristics. (4) As an important parameter to describe the degree of anisotropic state of rockfill, the orthotropic amplitude parameters reflected the strength characteristics from a microscopic perspective. The larger the anisotropic amplitude, the more obvious the anisotropy and the weaker the yield strength. Based on the grain arrangement fabric, the results also shown that the anisotropic state variables can describe the three-dimensional strength characteristics of rockfill well.

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