摘要
采用堆载法进行天然状态与饱和状态下强风化角岩边坡岩体的现场直接剪切试验,获得不同正应力水平下剪切应力-剪切变形关系曲线和剪切强度参数,对其剪切应力-剪切变形关系曲线特征和不同正应力作用下剪应力随正应力的变化规律以及水-力耦合作用对剪切强度与变形特性影响进行了分析。试验结果表明:岩体峰值剪切强度和屈服剪切强度均随正应力的增大而增大;天然状态和饱水状态下剪应力随不同正应力的变化趋势基本相同;岩体剪切强度随含水率的增大而减小,在低法向应力下尤其敏感;水对岩体强度参数中黏聚力c的弱化作用更加明显,同时加大了岩体变形量,延长了岩体变形过程;通过现场直剪试验测得的法向变形可以估算岩体的压缩模量,为边坡稳定性分析提供参数。
By using the method of preloading as vertical reaction, the field shearing test of heavily weathered hornstone side slope rock mass are carried out under the natural and the saturated condition, the shear stress - shear deformation relation curves under different normal stress levels and shear strength parameters are obtained. Based on the results of field shearing test, the effect of strength and deformation on mechanical-hydro coupling process and the change rule of the shear stress along with different normal stresses and the shear stress-deformation relation curves characteristics are analyzed. The test results indicate that, the peak shear strength and the yield shear strength increase with the increase of the normal stress; and the change of water content has not influence on the change rule of the shear stress along with different normal stresses. The shear strength decreases with the increase of water content; and it is especially sensitive under the low normal stress. Attenuated function for cohesive force of water is more obvious, and simultaneously has enlarged the rock mass amount of deformation and lengthened the rock mass distortion process. Modulus of compression of rock mass can be estimated by vertical deformation tested in the field shearing test.
出处
《岩土力学》
EI
CSCD
北大核心
2009年第12期3783-3787,3792,共6页
Rock and Soil Mechanics
基金
国家自然科学基金项目(No.10872207)资助
关键词
强风化角岩
边坡岩体
现场直接剪切试验
强度
应力-应变关系
heavily weathered hornstone
side slope rock mass
field shearing test
strength
stress-strain relationship
