含层理灰岩的巴西劈裂强度及拉裂损伤各向异性  

Brazilian Tensile Strength and Tensile Damage Anisotropy of Laminated Limestone

作　　者：钟帅 左双英[1] 罗沙 ZHONG Shuai;ZUO Shuang-ying;LUO Sha(College of Resources and Environment Engineering,Guizhou University,Guiyang 550025,China)

机构地区：[1]贵州大学资源与环境工程学院,贵阳550025

出　　处：《科学技术与工程》2020年第16期6578-6584,共7页Science Technology and Engineering

基　　金：国家自然科学基金(51469007);贵州省土木工程一流学科项目(QYNYL[2017]0013);贵州省山地地质灾害防治工程技术研究中心项目(黔科合平台人才[2017]5402号);贵州省科学技术厅社会发展科技攻关项目(黔科合支撑[2017]2866)。

摘　　要：为了研究不同角度层理对灰岩抗拉力学特性的影响,对7组不同角度层理灰岩进行巴西劈裂试验,根据岩石声发射累计振铃次数定义拉裂损伤变量,推导抗拉强度、劈裂模量及损伤变量随层理角度的变化规律。研究结果表明:①不同层理角度的灰岩,其受力变形过程基本一致,即经历压密、弹性和破坏3个阶段;②抗拉强度、拉伸模量随层理角度变化表现出明显的各向异性,在0°时最大,90°时最小;③基于岩体微元强符合Weibull分布及Lemaitre应变等效原理,通过拟合计算得到的损伤参数可以较好地反映7个角度灰岩样的损伤特性,损伤变量也具有各向异性特点,说明不同倾角的岩石参数在加载过程中有不同的劣化程度,同一应变水平下的损伤变量随着层理角度的增加出现下降的趋势。研究结果对于层状灰岩的试验研究、理论计算和工程建设具有一定的指导意义。In order to study the influence of different bedding angles on the tensile mechanical properties of limestone,Brazilian tensile test was carried out on 7 sets of different angles of limestone samples.The tensile damage variables were defined according to the cumulative times of the acoustic emission signals(the AE signals),and the tensile strength was derived.The results show that the limestone with different bedding angles is basically consistent in the process of stress deformation.It has three stages of compaction,elasticity and destruction.The tensile strength and tensile modulus show obvious anisotropy with the change of the bedding angles,which is the largest at 0°and the smallest at 90°.Based on the Weibull distribution and the Lemaitre strain equivalence principle,the damage parameters obtained by fitting calculation can better reflect the damage characteristics of the 7 limestone samples,and the damage variables also show anisotropy.Results show that the rock parameters with different bedding angles have different degrees of deterioration during the loading process,and the damage variables at the same strain level decrease with the increase of the bedding angles.The research results have certain guiding significance for the experimental research,theoretical calculation and engineering construction of layered limestone.

关 键 词：巴西劈裂试验 层状岩体 拉裂损伤 声发射系统 各向异性 

分 类 号：TU452[建筑科学—岩土工程]