摘要
针对岩石地基承载力问题,引入Hoek-Brown强度破坏准则,提出局部剪切破坏模式岩石地基承载力的计算表达式,基于极限平衡理论,建立破坏面上的静力平衡方程,推导出整体剪切破坏模式岩石地基承载力的计算公式.依据已有的成果假定空洞岩石地基顶板的冲切破坏体为一圆锥体,利用极限平衡法,得到了抗拉作用、抗剪作用及抗拉剪共同作用时下伏空洞地基极限承载力的计算表达式;并进一步通过模型试验验证了理论方法的合理性.结果表明:1)在计算完整岩石地基极限承载力时,采用整体剪切破坏模式得到的理论结果与实测结果较吻合;2)在计算空洞顶板极限承载力时,对比单独考虑冲切破坏面上的拉应力和剪应力作用得到的结果,考虑两者共同作用计算的结果更接近实测结果.
According to the problem of the bearing capacity of rock foundation the Hoek-Brown strength failure criterion is introduced and the calculation formula of the bearing capacity of rock foundation under local shear failure mode is proposed.Based on the limit equilibrium theory,the static equilibrium equation on the failure surface is established.The calculation formula of the bearing capacity of the rock foundation in the overall shear failure mode is derived.According to the existing research results it is assumed that the punching failure body of the roof of the hollow rock foundation is a cone,and the limit equilibrium method is used to obtain the calculation formula of the ultimate bearing capacity of the underlying cave foundation.When the tensile strength and the shear strength work alone,the tensile shear resistance works together.Furthermore,the rationality of the theoretical method is verified by model tests,The results indicated that:1)When calculating the ultimate bearing capacity of complete rock foundation,the theoretical results obtained by the overall shear failure mode are in good agreement with the measured results;2)When calculating the ultimate bearing capacity of the cavern roof,comparing the results of the tensile and shear stresses on the punching failure surface alone,the results of the joint action are considered to be closer to the measured results.
作者
刘一新
雷勇
邓加政
刘泽宇
欧阳鹏博
LIU Yixin;LEI Yong;DENG Jiazheng;LIU Zeyu;OUYANG Pengbo(Hunan Provincial Key Laboratory of Geotechnical Engineering for Stability Control and Health Monitoring,Hunan University of Science andTechnology,Xiangtan,Hunan 411201,China)
出处
《湖南城市学院学报（自然科学版）》
CAS
2019年第1期1-5,共5页
Journal of Hunan City University:Natural Science
基金
国家自然科学基金项目(51878270)
岩土工程稳定控制与健康监测湖南省重点实验室开放基金项目(E21618)
湖南工业大学研究生科研创新项目(CX1822)
关键词
岩石地基
剪切破坏
冲切破坏体
极限平衡法
极限承载力
模型试验
rock foundation
shear failure
punching failure body
limit equilibrium method
ultimate bearing capacity
model test
