基于持续屈服节理模型的节理直剪数值试验  

Numerical simulation of joint direct shear test based on continuously yielding joint model

作　　者：高艳华[1] 吴顺川[1] 王贺[2] 肖术[3] 

机构地区：[1]北京科技大学土木与环境工程学院,北京100083 [2]北京矿冶研究总院,北京100070 [3]长江三峡勘测研究院有限公司,湖南武汉430074

出　　处：《中南大学学报（自然科学版）》2016年第4期1253-1261,共9页Journal of Central South University:Science and Technology

基　　金：国家自然科学基金资助项目(51074014;51174014);科技北京百名领军人才培养工程项目(Z151100000315014);中国博士后科学基金资助项目(2015M570037)~~

摘　　要：根据山西平朔露天煤矿砂岩岩石及节理室内试验确定力学参数,采用块体离散元软件3DEC内置FISH语言编制程序,实现基于持续屈服节理模型的节理直剪数值试验,研究节理粗糙度、初始摩擦角和基本摩擦角差值对剪切强度的影响。研究表明:采用持续屈服节理模型的节理面数值剪切试验能反映节理剪切应力随剪切位移变化的4个阶段,即曲线上升—峰值—软化—残余应力阶段;与室内试验结果相比,持续屈服节理模型能较好地表征节理剪切峰值强度及峰值强度前剪切应力与剪切变形的非线性关系,且能较好地反映峰值强度后应变软化及残余强度等节理面力学性质;随粗糙度增大,剪切峰值强度按幂函数增大;随摩擦角差值增大,节理剪切峰值强度线性增大。According to laboratory experiments of standstone from Pingshuo open-pit coal mine in Shanxi Province, the mechanical parameters of rock and joint were determined. Based on continuously yielding joint model, joint direct shear numerical test was conducted by using FISH programs embedded within 3DEC software. The effects of joint roughness, the difference between initial friction angle and basic friction angle on the shear strength were studied. The results show that shear stress-displacement curves of joint obtained from numerical experiments can reflect four stages of joint shearing stress, i.e. increasing—peak—strain softening—residual strength. Compared with the results of indoor test, continuously yielding joint model incorporates irreversible non-linear behaviour from the onset of shear loading, and can effectively reflect the mechanical behaviour of joint strain-softening and residual strength after peak strength. With the increase of roughness, shear strength of joint increases with the power function, and it increases with the increase of the friction angle difference.

关 键 词：持续屈服节理模型 节理法向刚度 节理切向刚度 粗糙度 摩擦角 节理直剪试验 

分 类 号：TU45[建筑科学—岩土工程]