It is important to calibrate micro-parameters for applying partied flow code(PFC)to study mechanical characteristics and failure mechanism of rock materials.Uniform design method is firstly adopted to determine the mi...It is important to calibrate micro-parameters for applying partied flow code(PFC)to study mechanical characteristics and failure mechanism of rock materials.Uniform design method is firstly adopted to determine the microscopic parameters of parallel-bonded particle model for three-dimensional discrete element particle flow code(PFC3D).Variation ranges of microscopic of the microscopic parameters are created by analyzing the effects of microscopic parameters on macroscopic parameters(elastic modulus E,Poisson ratio v,uniaxial compressive strengthσc,and ratio of crack initial stress to uniaxial compressive strengthσci/σc)in order to obtain the actual uniform design talbe.The calculation equations of the microscopic and macroscopic parameters of rock materials can be established by the actual uniform design table and the regression analysis and thus the PFC3D microscopic parameters can be quantitatively determined.The PFC3D simulated results of the intact and pre-cracked rock specimens under uniaxial and triaxial compressions(including the macroscopic mechanical parameters,stress−strain curves and failure process)are in good agreement with experimental results,which can prove the validity of the calculation equations of microscopic and macroscopic parameters.展开更多
A new micromechanics constitutive model for pure dilatant transformation plasticity of structure ceramics is proposed in this paper.Based on the thermodynamics,micromechanics and microscale t→ m trans- formation mech...A new micromechanics constitutive model for pure dilatant transformation plasticity of structure ceramics is proposed in this paper.Based on the thermodynamics,micromechanics and microscale t→ m trans- formation mechanism analysis of the TZP and PSZ ZrO2-containing ceramics,an analytic expressions of the Helmholtz and complementary free energy of the constitutive element for the case of pure dilatant transforma- tion is derived for the first time in a self-consistent manner.By the analysis of energy dissipation in the for- ward and reverse transformations,the mieromechanics constitutive law is derived in the framework of Hill-Rice’s internal variable constitutive theory.展开更多
基金Projects(51474251,51874351)supported by the National Natural Science Foundation,China。
文摘It is important to calibrate micro-parameters for applying partied flow code(PFC)to study mechanical characteristics and failure mechanism of rock materials.Uniform design method is firstly adopted to determine the microscopic parameters of parallel-bonded particle model for three-dimensional discrete element particle flow code(PFC3D).Variation ranges of microscopic of the microscopic parameters are created by analyzing the effects of microscopic parameters on macroscopic parameters(elastic modulus E,Poisson ratio v,uniaxial compressive strengthσc,and ratio of crack initial stress to uniaxial compressive strengthσci/σc)in order to obtain the actual uniform design talbe.The calculation equations of the microscopic and macroscopic parameters of rock materials can be established by the actual uniform design table and the regression analysis and thus the PFC3D microscopic parameters can be quantitatively determined.The PFC3D simulated results of the intact and pre-cracked rock specimens under uniaxial and triaxial compressions(including the macroscopic mechanical parameters,stress−strain curves and failure process)are in good agreement with experimental results,which can prove the validity of the calculation equations of microscopic and macroscopic parameters.
基金The project is supported by the National Natural Science Foundation of Chin
文摘A new micromechanics constitutive model for pure dilatant transformation plasticity of structure ceramics is proposed in this paper.Based on the thermodynamics,micromechanics and microscale t→ m trans- formation mechanism analysis of the TZP and PSZ ZrO2-containing ceramics,an analytic expressions of the Helmholtz and complementary free energy of the constitutive element for the case of pure dilatant transforma- tion is derived for the first time in a self-consistent manner.By the analysis of energy dissipation in the for- ward and reverse transformations,the mieromechanics constitutive law is derived in the framework of Hill-Rice’s internal variable constitutive theory.
