基于平行黏结水弱化模型的页岩吸水软化离散元模拟  

Discrete element simulation of shale softening based on parallel-bonded water-weakening model

作　　者：胡训健 卞康[1,2] 刘建 谢正勇[3] 陈明 李冰洋 岑越 刘振平 HU Xun-jian;BIAN Kang;LIU Jian;XIE Zheng-yong;CHEN Ming;LI Bing-yang;CEN Yue;LIU Zhen-ping(State Key Laboratory of Geomechanics and Geotechnical Engineering,Institute of Rock and Soil Mechanics,Chinese Academy of Sciences,Wuhan 430071,China;University of Chinese Academy of Sciences,Beijing 100049,China;Hubei Road and Bridge Group Tianxia Construction Co.,Ltd.,Wuhan 430000,China)

机构地区：[1]中国科学院武汉岩土力学研究所岩土力学与工程国家重点实验室,湖北武汉430071 [2]中国科学院大学,北京100049 [3]湖北省路桥集团天夏建设有限公司,湖北武汉430000

出　　处：《岩土工程学报》2021年第4期725-733,I0003,I0004,共11页Chinese Journal of Geotechnical Engineering

基　　金：国家重点研发计划项目(2016YFC0401802);国家自然科学基金重点项目(51539002);国家自然科学基金项目(51779249);湖北省自然科学基金项目(2018CFB632)。

摘　　要：基于颗粒离散元方法,通过构建损伤因子,提出了平行黏结水弱化模型,建立了考虑胶结物力学参数的非均质性的颗粒流模型。通过室内试验和数值模拟计算结果的对比分析,验证了所提模型的正确性和适用性。主要结论如下:(1)岩石胶结物的非均质性对岩石宏观力学性质存在一定影响。随着均质性因子m的增加,岩石均质性增加,单轴抗压强度和弹性模量也随之增加,符合指数函数关系;(2)随着黏结面积系数的增加,岩石所储存的总应变能的总量和增速逐渐降低;(3)岩石在干燥状态下,微裂纹倾角集中于80°~100°,随着黏结面积系数的增加,微裂纹倾角的分布范围逐渐增加;(4)随着黏结面积系数的增加,岩石破裂面更为密集,且贯通性增强。研究结果可为深埋隧道遇水产生围岩大变形、库岸涉水边坡变形等问题的细观机制研究提供了一定的依据和理论指导。Based on the discrete element method of particles, by constructing damage factors, a parallel-bonded water-weakening model is proposed, and a particle flow code model considering the heterogeneity of the mechanical parameters of the cement is established. The comparison and analysis of the results of indoor experiments and numerical simulations verify the correctness and applicability of the proposed model. The main conclusions are as follows:(1) The heterogeneity of rock cement has certain influences on the macroscopic mechanical properties of rock. As the homogeneity factor increases, the homogeneity of the rock increases, and the uniaxial compressive strength and elastic modulus also increase, which conforms to the exponential function relationship.(2) With the increase of the bond area coefficient, the total amount and growth rate of the stored total strain energy in the rock gradually decrease.(3) In the dry state of the rock, the inclination angle of micro-cracks is concentrated in 80°~100°. As the bond area coefficient increases, the distribution range of the inclination angle of micro-cracks gradually increases.(4) With the increase of the bond area coefficient, the rock fracture surface is denser and the penetration is enhanced. The research results can provide a certain basis and theoretical guidance for the meso-mechanism study on the large deformation of the surrounding rock caused by the water in deep-buried tunnels and the deformation of the wading slope of the reservoir bank.

关 键 词：平行黏结水弱化模型 损伤因子 吸水软化 非均质性 黏结面积系数 

分 类 号：TU431[建筑科学—岩土工程]