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Abstract The deformation and failure characteristics of brittle-ductile-plastic transition，which is shown in the post-peak stage for Jinping deep marble，was simulated by clumped-particle model(CPM) of particle flow code(PFC)，and studied from the micro view. After a long process of trial-and-error calibration of laboratory test results，a set of micro parameters for Jinping deep marble were obtained. It is shown that a series of macroscopic mechanical properties of the synthetic rock，including the elastic modulus，Poisson?s ratio，uniaxial compressive and crack initiation strengths，stress-strain curves，the peak and residual strength envelops，the ratio of tensile to uniaxial compressive strength，and the failure patterns of synthetic rock samples，all agree well with the test results of Jinping deep marble. Study of regularities of crack development in synthetic rock samples at different confining pressures indicates that：The significant difference of development features of microcracks at different confining pressures is the main reason which leads to Jinping deep marble appearing brittle-ductile-plastic transition character；and the development of large number of tension cracks determines the brittle failure pattern of medium，while the rapid growth of shear cracks prompts the failure patterns of medium transition from brittle to ductile or plastic.
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Received: 08 June 2012
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2013, Vol. 32 
