工程科学学报，第37卷，第7期：831838,2015年7月 Chinese Journal of Engineering,Vol.37,No.7:831-838,July 2015 DOI:10.13374/j.issn2095-9389.2015.07.002:http://journals.ustb.edu.cn 基于颗粒流程序的非定常西原体模型 杨振伟，金爱兵四，高永涛，王凯，孙浩 北京科技大学土木与环境工程学院，北京100083 ☒通信作者，Email:jinaibing@vip.sina.com 摘要为实现岩石试样蠕变全过程的准确模拟，并从细观角度探究蠕变过程中微裂隙的发生和发展规律，在二维颗粒流程 序(P℉℃)中开发出具有黏弹塑性特征的西原体流变接触本构模型，进一步提出包含两种非定常元件的非定常西原体模型， 推导了模型本构关系和蠕变方程.在P℉C2”中调用自定义西原体流变模型，通过参数调试，获得与真实试样具有相同强度特 性的数值试样.以室内单轴压缩矯变试验数据为基础，在Mb中对模型非定常参数进行拟合反演分析.在此基础上，进行 单轴压缩蠕变试验的模拟，计算过程中分别采用定常和非定常两种模型，并对微裂隙进行监测.对比分析结果表明：定常模 型仅适用于衰减和稳定蠕变阶段：非定常模型也可用于描述加速蠕变阶段，从而准确模拟蠕变全过程：加速蠕变阶段主要是 由微裂隙的加速发展而产生，加速蠕变将导致试样剪切破坏 关键词岩石力学：蠕变：本构模型：颗粒流程序：裂隙 分类号TU452 Non-stationary Nishihara model in the particle flow code YANG Zhen-wei,JIN Ai-bing,GAO Yong-tao,WANG Kai,SUN Hao School of Civil and Environmental Engineering,University of Science and Technology Beijing,Beijing 100083,China Corresponding author,E-mail:jinaibing@vip.sina.com ABSTRACT In order to accurately simulate the whole process of rock creep and explore the generation and development of mirco- fractures from the mesoevel,a visco-elastoplastic Nishihara rheological constitutive model is developed in the two-dimensional particle flow code (PFC2).Then a non-stationary Nishihara model including two non-stationary elements is put forward in this article.A con- stitutive equation and a creep equation are derived based on the non-stationary Nishihara model.The user-defined Nishihara constitu- tive model is called in PFC2,and a numerical sample whose strength properties are the same as those of a real rock specimen is ac- quired by parameter testing.Using the data of uniaxial creep tests in laboratory,the non-stationary parameters are back analyzed in Matlab.At last,uniaxial creep tests are simulated using the stationary and non-stationary models,and micro-fractures are monitored. A comparison of these results show that the stationary model can only be used to describe the decay and steady stages,while the non- stationary model is also applicable to the accelerated stage,and thus can simulate the whole process of rock creep.Accelerated creep results from the accelerated development of mirco-fractures and leads to shear failure. KEY WORDS rock mechanics:creep:constitutive models;particle flow code;fractures 目前，对岩石流变特性的研究主要集中在室内试模型，所采用的流变参数大多为常量，无法描述岩石蠕 验·习、流变模型等方面.流变模型通常用三种理 变全过程.因此，许多学者开展了非线性和非定常流 想元件（弹性元件、黏性元件和塑性元件）组合而成， 变本构模型的研究，主要集中在两个方面：一是构造非 由于上述元件均为线性元件，组合出的模型均为线性 线性元件：二是将线性模型的流变参数视为非定常值. 收稿日期：2014-10-28 基金项目：国家自然科学基金资助项目(51074014)：中央直属高校基本科研业务费资助项目(FRF-SD-12O02A)工程科学学报，第 37 卷，第 7 期: 831--838，2015 年 7 月 Chinese Journal of Engineering，Vol． 37，No． 7: 831--838，July 2015 DOI: 10． 13374 /j． issn2095--9389． 2015． 07． 002; http: / /journals． ustb． edu． cn 基于颗粒流程序的非定常西原体模型 杨振伟，金爱兵，高永涛，王 凯，孙 浩 北京科技大学土木与环境工程学院，北京 100083  通信作者，E-mail: jinaibing@ vip． sina． com 摘 要 为实现岩石试样蠕变全过程的准确模拟，并从细观角度探究蠕变过程中微裂隙的发生和发展规律，在二维颗粒流程 序( PFC2D ) 中开发出具有黏弹塑性特征的西原体流变接触本构模型，进一步提出包含两种非定常元件的非定常西原体模型， 推导了模型本构关系和蠕变方程． 在 PFC2D中调用自定义西原体流变模型，通过参数调试，获得与真实试样具有相同强度特 性的数值试样． 以室内单轴压缩蠕变试验数据为基础，在 Matlab 中对模型非定常参数进行拟合反演分析． 在此基础上，进行 单轴压缩蠕变试验的模拟，计算过程中分别采用定常和非定常两种模型，并对微裂隙进行监测． 对比分析结果表明: 定常模 型仅适用于衰减和稳定蠕变阶段; 非定常模型也可用于描述加速蠕变阶段，从而准确模拟蠕变全过程; 加速蠕变阶段主要是 由微裂隙的加速发展而产生，加速蠕变将导致试样剪切破坏． 关键词 岩石力学; 蠕变; 本构模型; 颗粒流程序; 裂隙 分类号 TU452 Non-stationary Nishihara model in the particle flow code YANG Zhen-wei，JIN Ai-bing ，GAO Yong-tao，WANG Kai，SUN Hao School of Civil and Environmental Engineering，University of Science and Technology Beijing，Beijing 100083，China  Corresponding author，E-mail: jinaibing@ vip． sina． com ABSTＲACT In order to accurately simulate the whole process of rock creep and explore the generation and development of mirco￾fractures from the meso-level，a visco-elastoplastic Nishihara rheological constitutive model is developed in the two-dimensional particle flow code ( PFC2D ) ． Then a non-stationary Nishihara model including two non-stationary elements is put forward in this article． A con￾stitutive equation and a creep equation are derived based on the non-stationary Nishihara model． The user-defined Nishihara constitu￾tive model is called in PFC2D，and a numerical sample whose strength properties are the same as those of a real rock specimen is ac￾quired by parameter testing． Using the data of uniaxial creep tests in laboratory，the non-stationary parameters are back analyzed in Matlab． At last，uniaxial creep tests are simulated using the stationary and non-stationary models，and micro-fractures are monitored． A comparison of these results show that the stationary model can only be used to describe the decay and steady stages，while the non￾stationary model is also applicable to the accelerated stage，and thus can simulate the whole process of rock creep． Accelerated creep results from the accelerated development of mirco-fractures and leads to shear failure． KEY WOＲDS rock mechanics; creep; constitutive models; particle flow code; fractures 收稿日期: 2014--10--28 基金项目: 国家自然科学基金资助项目( 51074014) ; 中央直属高校基本科研业务费资助项目( FＲF--SD--12--002A) 目前，对岩石流变特性的研究主要集中在室内试 验［1 － 3］、流变模型［4 － 6］等方面． 流变模型通常用三种理 想元件( 弹性元件、黏性元件和塑性元件) 组合而成， 由于上述元件均为线性元件，组合出的模型均为线性 模型，所采用的流变参数大多为常量，无法描述岩石蠕 变全过程． 因此，许多学者开展了非线性和非定常流 变本构模型的研究，主要集中在两个方面: 一是构造非 线性元件; 二是将线性模型的流变参数视为非定常值．