Abstract：To explore how the strength，deformation and failure characteristics of layered rock mass change with bedding angle and specimen scale，3D printing technology is adopted to produce bedding specimens of different angles and scale，and the uniaxial compression test and Brazilian splitting test are conducted. Besides，the combined finite-discrete element method(FDEM) is employed to testify the laboratory results. Three findings are reported as below. Firstly，compressive strength，elastic modulus and deformation modulus have a“U-shaped” curve relationship with bedding angle，respectively. When bedding angle is 90°，the values of these three factors are obviously higher than the results under the condition of other bedding angles. Tensile strength has a negative correlation with bedding angle. When bedding angle is 0°，the tensile strength is apparently lower than that of homogeneous specimens. Secondly，the specimens subjected to uniaxial compression load feature tension- dominated failure(with the bedding angles of 0°and 90°) and shear-dominated failure(with the bedding angles of 45°and 67.5°). As bedding angle increases，failure mode gradually transits from ductile failure to brittle failure. The specimens suffering from Brazilian splitting test show tension-dominated failure and the fractures assume linear-type(with the bedding angles of 0° and 90°) and arc-type(with the bedding angle of 45°). Lastly，as specimen scale gradually increases，compressive strength tends to be stable and peak strain decreases gradually and tends to stabilize around 0.005. Tensile strength and specimen scale have an“inverted U-shaped”curve relationship，elastic modulus and deformation modulus fluctuates around 2.1 GPa，and these three factors don?t show stable tendency.
田永超1，何 璠2，殷 源2. 基于3D打印和FDEM算法的层状岩体力学特性研究[J]. 岩石力学与工程学报, 2023, 42(S1): 3331-3343.
TIAN Yongchao1，HE Fan2，YIN Yuan2. Study on mechanical properties of layered rock mass based on 3D printing technology and FDEM algorithm. , 2023, 42(S1): 3331-3343.
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2023, Vol. 42 
