学术论文

      基于颗粒流原理的岩石类材料细观参数的试验研究

      Experimental study on microscopic parameters of brittle materials based on particle flow theory

      摘要:
      材料的宏观力学特征与细观参数密切相关,基于颗粒流原理探究两者间的定量相关性,结合大理岩室内加、卸荷试验确定适用于岩石类材料(如大理岩)的细观参数,为细观分析岩石类材料卸荷破坏机理提供依据。结果表明:①平行黏结弹性模量是宏观弹性模量的主要控制因素,两者之间呈线性关系;泊松比与黏结弹性模量间呈多项式关系。材料弹性模量与泊松比的调试应以颗粒黏结弹性模量与平行黏结弹性模量作为主要对象。②平行黏结切向强度均值与平行黏结法向强度均值共同作用改变材料的应力–应变曲线,平行黏结法向强度均值与峰值应力间呈多项式关系;平行黏结切向强度均值与峰值应力间呈对数关系。③颗粒法向强度与切向强度之间的相对关系是裂纹分布多样化的本质原因:平行黏结法向(切向)强度均值与其标准差的比值在1附近时,岩样共轭破坏,比值增大或减小均会引起模型破坏面向剪切转变,同时平行黏结切向强度均值或其标准差增大会改变贯通性主破坏面的方向。④摩擦因数增加,岩样次生破坏面减少,但不会改变破坏面的方向。⑤大理岩室内试验的宏观力学特征表明通过正交设计试验可以得到基本合理的细观参数。
      Abstract:
      The macroscopic mechanical properties of materials are closely related to their microscopic parameters. The quantitative correlation between them is explored based on the theory of particle flow code. The microscopic parameters are confirmed through laboratory tests on marble under loading and unloading, which are suitable for brittle materials (such as marble), so as to provide the foundation for microscopic analysis of the unloading failure mechanism of brittle materials. The results show that: (1) Young's modulus of parallel-bond is the main controlling factor of macroscopic Young's modulus, and there is a linear relationship between them. Poisson's ratio is the polynomial function of Young's modulus of bond. The main objects of debugging materials of Young's modulus and Poisson's ratio are Young's modulis of parallel-bond and contact. (2) The joint action between the mean parallel-bond normal strength and shear strength influences the stress-strain curve of materials, and the mean parallel-bond normal strength is the polynomial function of the peak stress. The relationship between the mean parallel-bond shear strength and the peak stress is a log function one. (3) The essential reason for diversity of crack distribution is the relative relationship between normal strength and shear strength of particles: the failure type is conjugate damage when the ratio of the mean value of parallel-bond normal (shear) strength to the standard deviation is around 1; increase or decrease of the ratio causes the change from conjugate to shear damage, and increase of the mean value or standard deviation of parallel-bond shear strength causes the change of the coefficient, however, the direction of failure surface will not change. (5) The macroscopic mechanical properties of marble tests show that the basic reasonable microscopic parameters can be obtained through orthogonal tests.
      作者: 丛宇 [1] 王在泉 [2] 郑颖人 [3] 冯夏庭 [4]
      Author: CONG Yu [1] WANG Zai-quan [2] ZHENG Ying-ren [3] FENG Xia-ting [4]
      作者单位: 中国科学院武汉岩土力学研究所,湖北武汉 430071; 后勤工程学院建筑工程系,重庆 400041 青岛理工大学理学院,山东青岛,266033 后勤工程学院建筑工程系,重庆,400041 中国科学院武汉岩土力学研究所,湖北武汉,430071
      刊 名: 岩土工程学报 ISTICEIPKU
      年,卷(期): 2015, (6)
      分类号: TU45
      在线出版日期: 2015年7月7日
      基金项目: 国家自然科学基金项目(41372298,11232024,41320104005);国家重点基础研究发展计划(973计划)项目