岩石微观颗粒接触特性的试验研究  

EXPERIMENTAL STUDY OF INTER-GRANULAR PARTICLES BONDING BEHAVIORS FOR ROCK MICROSTRUCTURE

作　　者：蒋明镜[1,2] 白闰平[1,2] 刘静德[1,2] 周雅萍[1,2] 

机构地区：[1]同济大学地下建筑与工程系,上海200092 [2]同济大学岩土及地下工程教育部重点实验室,上海200092

出　　处：《岩石力学与工程学报》2013年第6期1121-1128,共8页Chinese Journal of Rock Mechanics and Engineering

基　　金：国家重点基础研究发展计划(973)项目(2011CB013504)

摘　　要：微观上,岩石是由许多大小不等的颗粒和粒间填充的胶结物构成,不同位置的胶结厚度不同。岩石的这种微观结构特征从根本上决定其宏观力学响应,从微观尺度出发采用离散元数值模拟有利于探索岩石宏观力学特性的微观机制。基于这一思路,通过室内铝棒胶结模型试验,研究不同胶结厚度下胶结颗粒在压剪扭加载作用下的接触力学特性,发现胶结铝棒在不同胶结物质、不同胶结厚度下的力学响应均呈现出一定的相似性。将蒋明镜提出的岩石微观胶结模型与D.O.Potyondy和P.A.Cundall提出的岩石微观接触力学模型进行对比分析发现,蒋明镜模型提出的破坏准则与岩石的实际较为符合,进一步为离散元模拟岩石奠定基础。From the microscopic point of view,rocks can be regarded as granular particles with different sizes.These granular particles are basically bonded by inter-granular cementation with various bonding thicknesses.The microstructure features roughly determine the macroscopic mechanical responses of rocks.Therefore,numerical simulations based on discrete element method can be helpful for understanding the microscopic mechanism of rock macro-mechanics.Consequently,the contact mechanical characteristics of inter-particles are studied by compression,shear and contortion model tests in laboratory.In addition,a comparative study of this bonding model and grain-cement model of rock performed by D.O.Potyondy and P.A.Cundall is carried out.These model tests are conducted on cement/epoxy resin bonding aluminum rods.The test results show that the bonds,either at different bond thicknesses or with different bond materials,show similar mechanical behaviors,suggesting a good foundation for the applicability of discrete element simulation.The results show that this bonding model to describe for rock behaviors is more accurate than grain-cement model proposed by D.O.Potyondy and P.A.Cundall.

关 键 词：岩石力学 岩石微观结构 离散单元法 胶结模型 胶结厚度 

分 类 号：TU45[建筑科学—岩土工程]