摘要
节理剪切特性是影响岩体稳定性的重要因素,因此根据天然原岩节理起伏形貌曲线,采用颗粒流数值计算方法开展了天然多形貌无充填及充填厚度为15 mm和75 mm的节理剪切特性试验,分析节理起伏形貌和充填厚度对剪切特性及抗剪强度的影响.研究结果表明:(1)随着充填厚度的增大,起伏形貌对节理峰前硬化、峰后软化的峰值特征影响降低,峰后软化程度下降.(2)同起伏形貌的节理随着充填厚度的增大,试样由节理剪切破坏向软弱夹层剪切破坏过渡.充填度小于2时,主要是节理剪切破坏和节理-夹层耦合破坏;充填度大于2时,主要发生软弱夹层剪切破坏.(3)充填度小于2时,结构面峰值抗剪强度随充填度增大呈减小规律;当充填度大于2时,结构面峰值抗剪强度无明显变化.
The shear characteristics of joints is an important factor affecting the stability of rock masses.Based on the natural joint surface undulation profiles,numerical simulations using the Discrete Element Method(DEM)are conducted to investigate the shear characteristics of joints with natural and filled surfaces at thicknesses of 15 mm and 75 mm.The study analyzes the effects of joint undulation and filling thickness on shear characteristics and shear strength.The research findings indicate the following:(1)With the increase in filling thickness,the influence of undulation on the peak hardening and post-peak softening features of joints decreases,and the degree of post-peak softening decreases.(2)For joints with the same undulation profile,as the filling thickness increases,the failure mode transitions from joint shear failure to shear failure in the weak interlayer.When the filling ratio is less than 2,the primary failure modes are joint shear failure and joint-interlayer coupling failure.When the filling ratio is greater than 2,the predominant failure mode is shear failure in the weak interlayer.(3)When the filling ratio is less than 2,the peak shear strength of the structural surface decreases with the increase in filling ratio.However,when the filling ratio is greater than 2,there is no significant change in the peak shear strength of the structural surface.
作者
朱跨丰
罗战友
吴强
吴晖
李干
ZHU Kuafeng;LUO Zhanyou;WU Qiang;WU Hui;LI Gan(Institute of Rock Mechanics,Ningbo University,Ningbo 315211,China;Ningbo Shiyu Railway Investment Development Co.,Ltd.,Ningbo 315101,China)
出处
《宁波大学学报（理工版）》
CAS
2024年第5期35-40,共6页
Journal of Ningbo University：Natural Science and Engineering Edition
基金
国家自然科学基金(42277147).
关键词
充填节理
抗剪强度
剪切特性
数值模拟
起伏形貌
filling joint
shear strength
shear properties
numerical simulation
undulating morphology
