摘要
循环加-卸载岩石本构模型是预测压气储能洞室长期稳定性的关键,但目前还没有适用的本构模型,因此,提出了一种能够描述岩石循环加载和卸载的本构模型。鉴于岩石在循环作用下损伤不断累积,将基于Weibull分布的岩石损伤软化模型进行拓展,并用内变量疲劳本构模型描述每个循环的初始模量和卸载模量的变化,进而得到循环加-卸载作用下的岩石本构模型,然后将该模型与现有的试验结果进行对比。该模型物理意义明确,涉及的参数较少,且便于拟合。提出的循环加-卸载下岩石本构模型对试验数据拟合效果较好,能较准确地反映循环荷载上、下限值对应的轴向应变,也能反映出循环内部变形模量衰减的趋势。该模型的成功建立为循环加-卸载下岩石本构模型的研究提供了新思路。
Constitutive models for rock under cyclic loading and unloading, which are rarely reported in literatures, are critical to predict the long-term stability of CAES caverns. A constitutive model for rock subjected to cyclic loading and unloading is proposed. The model for rock softening and damage, which is based on Weibull random distribution, is expanded. The fatigue constitutive model with internal variables is employed to describe the variations of initial modulus and unloading modulus during every cycle. Then, a constitutive model for rock under cyclic loading and unloading is obtained. The results from proposed constitutive model is subsequently compared with the existing test results. The physical meaning of this model is explicit. The parameters involved in the model are less and can be easily fitted. The proposed model can represent the relationship of the stress and strain of every cycle and shows a good agreement with the results of laboratory tests. The successful establishment of the proposed model can provide a new idea to the researches on constitutive models for rocks under cyclic loading and unloading.
出处
《岩土力学》
EI
CAS
CSCD
北大核心
2015年第12期3354-3359,共6页
Rock and Soil Mechanics
基金
国家自然科学基金资助(No.51278378)
国家高技术研究发展计划(863计划)项目(No.SS2012AA052501)~~
关键词
循环加-卸载
岩石
本构模型
cyclic loading and unloading
rock
constitutive model
