HYBRID CONTINUUM - DISCONTIN UUM MODELLING OF ROC K FRACUTRE PROCESS IN BRAZILIAN TENSILE ST RENGTH TEST

Huaming An, Hongyuan Liu, Xuguang Wang, Jianjun Shi, Haoyu Han
2017 Civil Engineering Journal  
A hybrid continuum-discontinuum method is introduced to model the rock failure process in Brazilian tensile strength (BTS) test. The key component of the hybrid continuum-discontinuum method, i.e. transition from continuum to discontinuum through fracture and fragmentation, is introduced in detail. A laboratory test is conducted first to capture the rock fracture pattern in the BTS test while the tensile strength is calculated according to the peak value of the loading forces. Then the proposed
more » ... method is used to model the rock behaviour during BTS test. The stress propagation is modelled and compared with those modelled by finite element method in literatures. In addition, the crack initiation and propagation are captured and compared with the facture patter in laboratory test. Moreover, the force-loading displacement curve is obtained which represents a typical brittle material failure process. Furthermore, the stress distributions along the vertical direction are compared with the theoretical solution. It is concluded that the hybrid continuum-discontinuum method can model the stress propagation process and the entire rock failure process in BTS test. The proposed method is a valuable numerical tool for studying the rock behaviour involving the fracture and fragmentation processes. KEYWORDS Hybrid Continuum-Discontinuum, Brazilian Tensile Strength Test, Rock Failure Process, Crack Initiation and Propagation Numerical methods can be classified according to the hypothesis that the rock is modelled as a continuous or discontinuous materials. Therefore, there are three kinds of numerical methods, i.e. continuum method, discontinuum method, and combined continuum-discontinuum method. As the rock can be considered as continuous material before fractures and cracks occur while it can be treated as discontinuous material after fracture and fragmentation, the combined continuumdiscontinuum method might be a better choice to model the entire rock failure processes. Article no. 21 THE CIVIL ENGINEERING JOURNAL 3-20ZZ
doi:10.14311/cej.2017.03.0021 fatcat:tahjskoftrez7ef6ufdk6u55z4