Mechanical behaviors of fractured rock masses based on synthetic rock mass simulation

• Main Authors: Hua-En Zheng, 鄭華恩
• Other Authors: Yong-Ming Tien
• Format: Others
• Language: zh-TW
• Published: 2019
• Online Access: http://ndltd.ncl.edu.tw/handle/ge7cn3

碩士 === 國立中央大學 === 土木工程學系 === 107 === This paper presents the mechanical behaviors of fractured rock masses for various geometrical conditions by using the Particle Flow Code (PFC3D). A specified rock mass size is assigned by software FracMan to generate discrete fracture network (DFN) then the fracture data were input into smooth joint model (SJM), combing with bonded particle model (BPM) by PFC3D to produce synthetic rock mass (SRM). SRM was used to simulate the mechanical behaviors based on macroscopically isotropic/anisotropic rock under triaxial test, calculating major principal stress, young's modulus, crack numbers, stress-axial strain relationship and volumetric strain-axial strain relationship. The research projects are including: (1) Set a series of parameters to study the effect of the fracture intensity and the fracture size on the mechanical behaviors of the fractured rock mass. (2) Select one set of in-situ fracture data which was uniformly random distribution (κ = 0) to generate isotropic rock for triaxial test then observe the failure process and the failure mode. Compare our result with the uniaxial test observations of Basu et al. (2013), and the triaxial test result of Bieniawski (1967), Wawersik and Fairhust (1970) and Elliott (1982). (3) Set up single fracture set of seven angles to generate anisotropic rock for triaxial test then observe the failure process and the failure mode. The experimental results of Tien et al. (2006) and Khanlari et al. (2014) were compared with the failure mode of the test, and the maximum principal stress of the test results was compared with the failure criteria proposed by Tien and Kuo (2006). (4) To verify the conceptual model proposed by Hoek and Brown (1980, 1988), generating SRM with one to four sets of fracture then act the uniaxial test. Furthermore, to verify the accuracy of the Young’s modulus of the transversely isotropic rock mass of one set of fracture, using the method proposed by Amadei (1983) to determine elastic constants of the transversely isotropic rock mass.