摘要
寒区岩石受到荷载及冻融循环的作用,考虑岩石微元破坏的特点,将其简化为冻融损伤、受荷损伤及未损伤3部分组成。基于损伤力学理论,通过探讨冻融损伤变量、受荷损伤变量以及总损伤变量之间的关系,假定岩石微元破坏符合D-P准则,建立冻融与荷载作用下考虑残余强度的岩石损伤本构模型,并由冻融砂岩力学特性试验验证其合理性;在此基础上探讨了模型参数对岩石损伤本构关系的影响。结果表明:不同冻融次数及围压作用下的模型理论曲线与试验曲线较为吻合,较好地描述了岩石变形的全过程;模型参数对岩石损伤前及破坏后残余段的应力应变曲线几乎没有影响,但对损伤阶段的影响较大。研究成果将会对寒区岩石损伤演化认知具有较好的参考价值。
Under the action of load and freeze-thaw cycle and considering the characteristics of rock micro-unit damage,the cold rock is simplified into three parts:freeze-thaw damage,injury damage and non damage.Based on damage mechanics theory and by discussing the relationship between the freeze-thaw damage variable,the injury damage variable and the total damage variable when rock micro-unit strength satisfies Weibull random distribution,a considering residual strength damage constitutive model for rock under the action of freeze-thaw and load is established by adopting D-P criterion,and the model rationality is verified by the test of freeze-thaw sandstone mechanical properties.On this basis,the influence of model parameters on the rock damage model is discussed.Research shows that:the theoretical curves of different freeze-thaw times and confining pressures were in good agreement with the experimental curve,it not only can give a good description of the rock pre-peak strain-stress curve,and it can also be an indication of the post-peak strain softening properties and the residual strength characteristics.The model parameters have little effect on the stress-strain curves of residual segments before and after the damage,but it has a great influence on the damage section.The research results are of a good reference value for the cognition of rock damage evolution in cold regions.
作者
张慧梅
孟祥振
彭川
杨更社
叶万军
申艳军
刘慧
ZHANG Hui-mei;MENG Xiang-zhen;PENG Chuan;YANG Geng-she;YE Wan-jun;SHEN Yan-jun;LIU Hui(College of Sciences,Xi’an University of Science and Technology,Xi’an 710054,China;College of Civil and Architectural Engineering,Xi’an University of Science and Technology,Xi’an 710054,China;No.5 Engineering Construction Co.,Ltd.,of China Gezhouba Croup Co.,Yichang 443002,China)
出处
《西安科技大学学报》
CAS
北大核心
2018年第2期260-265,共6页
Journal of Xi’an University of Science and Technology
基金
国家自然科学基金(11172232
51774231
41772333)
陕西省重点科技创新团队计划(2014KCT-30)
关键词
寒区岩石
残余强度
D-P准则
本构模型
模型参数
cold rock
residual strength
D-P criterion
constitutive model
model parameter
