温湿度联合作用下软岩粗粒料三轴剪切力学特性研究  

Triaxial shear mechanical properties of weak rock coarse granular materials subjected to temperature and relative humidity

作　　者：毛航宇 刘斯宏[1,2] 沈超敏 王涛[3] 王柳江 MAO Hangyu;LIU Sihong;SHEN Chaomin;WANG Tao;WANG Liujiang(College of Water Conservancy and Hydropower,Hohai University,Nanjing 210024,China;International Joint Laboratory of Long-Term Behaviour&Environmentally Friendly Rehabilitation Technologies on Dams,Nanjing 210024,China;College of Civil and Transportation Engineering,Hohai University,Nanjing 210024,China)

机构地区：[1]河海大学水利水电学院,江苏南京210024 [2]大坝长效特性及环保修复技术中西联合实验室,江苏南京210024 [3]河海大学土木与交通学院,江苏南京210024

出　　处：《岩土工程学报》2024年第3期587-595,共9页Chinese Journal of Geotechnical Engineering

基　　金：国家自然科学基金青年基金项目(52209160,52009036);国家自然科学基金面上项目(51979091);中国博士后科学基金面上项目(2023M730933);江苏省卓越博士后计划项目(2022ZB186)。

摘　　要：软岩粗粒料具有风化程度高、易破碎等特点,其力学特性易受温湿环境的影响。利用自主研制的温湿控制粗粒料大型三轴仪开展了一系列控制温湿度的软岩粗粒料三轴剪切试验,探究了温湿度对软岩粗粒料剪切强度、剪切变形、颗粒破碎及临界状态的影响规律。研究发现:(1)软岩粗粒料的力学行为受温湿度影响显著,随着温湿度的升高,其峰值剪切强度降低,剪缩变形量增加,颗粒破碎程度增大,p-q空间内的临界状态线向下旋转,同时e-(p/pa)^(ξ)空间内的临界状态线向下平移;(2)温湿度对力学特性的影响在低围压条件下更显著,随着围压的升高,温湿度引起的差异性变小。(3)基于不同温湿度作用下的颗粒破碎等效对应关系,实现了不同温湿工况下颗粒破碎及临界状态试验规律的归一化,为建立统一考虑温湿度影响的本构模型提供思路。The weak rock coarse granular materials have the characteristics of high weathering degree and low crushing strength,and their mechanical properties are easily affected by the temperature and humidity environment.A series of triaxial shear tests on the weak rock coarse granular materials are carried out by controlling the temperature and relative humidity.Based on the test results,the influences of the temperature and relative humidity on the shear strength,shear deformation,particle breakage and critical state are analyzed.The results show that the mechanical behavior of the weak rock coarse granular materials is greatly affected by the temperature and relative humidity.With the increase of the temperature and relative humidity,the peak strength decreases,the shear shrinkage deformation increases,and the particle breakage degree increases.The increase of the temperature and relative humidity causes the critical state line to rotate downward in the p-q plane and to drift downward in the e-(p/pa)^(ξ) plane.The influences of the temperature and relative humidity on the mechanical properties of the weak rock coarse granular materials are more significant under low confining pressures,and the differences of the test results are less significant with the increase of the confining pressure.Based on the equivalent corresponding relationships of particle breakage under different temperature and relative humidity conditions,the discrete test results of the particle breakage and critical state are transformed into the normalized results.The research results can be used to establish the constitutive model considering the influences of the temperature and relative humidity.

关 键 词：软岩粗粒料 温湿效应 颗粒破碎 临界状态 归一化分析 

分 类 号：TU411[建筑科学—岩土工程]