摘要
利用水泥砂浆材料浇注3组不同表面形貌的节理试件,由常法向应力下的直剪试验研究节理的剪切力学性质,并分析法向应力、三维形貌特征对抗剪强度的影响。直剪试验结果表明:峰值剪胀角与法向应力成反变化关系,与粗糙程度呈正变化关系;峰值抗剪强度与法向应力、粗糙程度均呈正变化关系。分析了JRC-JCS准则计算值偏低于试验值的原因,根据试验现象建议采用三维形貌参数、抗拉强度描述节理的剪切强度。对比分析了含三维形貌参数的峰值抗剪强度准则,建议低法向应力水平下采用双曲线形式的峰值剪切强度准则估算岩石节理的峰值抗剪强度。
Three groups of rock joints with different morphologies are made from cement mortar materials. The shear behavior is investigated by means of the direct shear tests under constant normal stress condition. The effects of the applied normal stress and morphology on the shear strength are analyzed. According to the experimental results, it can be found that the peak dilatancy angle decreases with the increasing normal stress and increases with the increasing roughness. The shear strength increases with the increasing normal stress and also the roughness of rock joints. The reason of underestimation by JRC-JCS criterion is analyzed, and it is suggested to adopt the three-dimensional morphology parameters and tensile strength to capture the characteristics of the peak shear strength. The hyperbolic criterion is suggested to use as a predictive tool to assess the peak shear strength of rock joints under low normal stress level based on the comparisons among several criteria with three-dimensional morphology parameters.
出处
《岩土工程学报》
EI
CAS
CSCD
北大核心
2014年第5期873-879,共7页
Chinese Journal of Geotechnical Engineering
基金
国家自然科学重点基金项目(41130742)
国家重点基础研究发展计划(973计划)项目(2014CB046904)
国家自然科学基金项目(40972178)
湖北省自然科学基金创新群体项目(2011CDA119)
中国博士后科学基金项目
关键词
节理
三维形貌参数
抗拉强度
抗剪强度准则
rock joint
three-dimensional morphology parameter
tensile strength
shear strength criteria