摘要
近年来,国内外一些学者基于围压卸荷试验,对岩石的卸荷力学特性和本构模型进行了大量的研究,取得了丰硕的成果。卸荷条件下岩石的强度特征、变形规律和破坏模式与加载状态相比有着显著的区别,通过围压卸荷试验可以发现,卸荷条件下岩石张性裂缝发育,扩容显著,通常呈张剪性破坏,且卸荷速率、围压和应力路径等因素均对其变形破裂机制有着较大的影响。卸荷条件下岩石的本构模型通常分为唯象学本构模型和细观力学本构模型,唯象学模型忽视了岩石卸荷渐进破坏的演化机制,细观力学本构模型则未考虑微裂纹群及数学简化引起的误差等,这些问题使得未来的卸荷岩石力学研究工作充满了机遇与挑战。
In recent years, scholars have made plenty of researches on the mechanical characteristics and constitu-tive models of unloading rock through the unloading tests of rock specimen. Also, substantial achievements have been obtained. Compared with loading condition, rock performs differently in many aspects under unloading condi-tion ,such as strength characteristics, deformation regularities and failure modes. Unloading rock has significant tensile cracks and volume dilatation, and always performs as tensile-shear failure. Moreover, deformation and fail-ure mechanism are impacted greatly by unloading speed, confining pressure and stress path. The constitutive models of unloading rock can be divided into phenomenological constitutive model and micro-mechanical constitutive model. The former does not consider the failure evolution mechanism of unloading rock, while the latter does not consider the micro crack groups and the error caused by mathematical simplification. These scientific problems make the fu-ture of unloading rock mechanics research work full of opportunities and challenges.
出处
《长江科学院院报》
CSCD
北大核心
2017年第7期87-93,共7页
Journal of Changjiang River Scientific Research Institute
基金
国家重点基础研究发展计划(973)项目(2015CB057905)
国家自然科学基金面上项目(51279202)
NSFC-云南联合基金重点支持项目(U1402231)
关键词
岩石力学
卸荷试验
变形特征
破裂特征
本构模型
rock mechanics
unloading test
deformation feature
fracture characteristics
constitutive model
