Numerical Tests Research on Mechanical Parameters of Rockmass considering Structural Plane Combination Characteristics

Abstract

It is essential to determine rockmass mechanical parameters in stability assessment. The structural z is the main factor in this regard, and we know little about the relationship between mechanical parameters and multiple structure planes. In this paper, we have conducted a series of numerical tests to obtain mechanical parameters for a dam foundation in Southwest China. The biaxial numerical test was performed based on the discrete element method. This numerical test considers the spacing, types, dip angles, and size effect. We established a relationship of mechanical parameters between small size lab samples and large size field samples. We forecasted the strength parameters for a spillway slope in Southwest China. The dip angle has a significant effect on the slope strength and stability. In this case, the rockmass fracture stress-dip angle curve forms a U-shaped distribution. The X-shaped double structure plane demonstrates severe strength weakening relative to a single structure plane. As structure plane spacing reaches a certain level, its influence on rockmass strength diminishes. The elementary volume of the rockmass for dam foundation analysis is about 4 m × 4 m × 4 m.

Simulation Study on the Size Effect of Secant Modulus of Rocks Containing Rough Joints

“…For this research, Chen et al [17] analyzed the size effect of the degree of rock mass block and determined the REV size of the rock mass. Wei et al [18] obtained the rock characteristic size of a particular engineering case, which was 4 m. Loyola et al [19] evaluated the REV of fractured rocks based on the central limit theorem (CLT). Peng et al [20] analyzed the size effect through PFC software and obtained an REV size of 16 m. Hu et al [21] obtained the characteristic size expression of the elastic modulus by simulating the uniaxial compression of rocks with rough joints.…”