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
提出了一种建立非饱和土体宏-细观参数之间关系的方法,来建立在不同孔隙比和含水率等初始条件下非饱和土在不同应力路径下的离散元计算模型;通过编制离散元程序,基于接触粘结模型,对现有的PFC3D(Particle Flow Code in three dimensions...提出了一种建立非饱和土体宏-细观参数之间关系的方法,来建立在不同孔隙比和含水率等初始条件下非饱和土在不同应力路径下的离散元计算模型;通过编制离散元程序,基于接触粘结模型,对现有的PFC3D(Particle Flow Code in three dimensions)离散元程序进行改进,从而对在不同颗粒间粘结强度下的离散元试样进行一维固结的数值模拟试验来确定其结构屈服应力,并以结构屈服应力为桥梁建立颗粒间粘结强度随含水率变化的函数关系,最后建立能够反映真实非饱和土试样颗粒级配和在不同含水量下的离散元数值模型,为通过PFC3D等三维离散元软件研究非饱和土的基本力学特性提供思路.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.
文摘提出了一种建立非饱和土体宏-细观参数之间关系的方法,来建立在不同孔隙比和含水率等初始条件下非饱和土在不同应力路径下的离散元计算模型;通过编制离散元程序,基于接触粘结模型,对现有的PFC3D(Particle Flow Code in three dimensions)离散元程序进行改进,从而对在不同颗粒间粘结强度下的离散元试样进行一维固结的数值模拟试验来确定其结构屈服应力,并以结构屈服应力为桥梁建立颗粒间粘结强度随含水率变化的函数关系,最后建立能够反映真实非饱和土试样颗粒级配和在不同含水量下的离散元数值模型,为通过PFC3D等三维离散元软件研究非饱和土的基本力学特性提供思路.