摘要
首先分析饱和砂岩所经历的冻融作用的特点,认为冻融作用是一种低周疲劳荷载,且砂岩冻融循环作用下的受力状态可简化为单向拉伸荷载的循环作用。基于以上分析,在疲劳损伤理论的基础上,建立砂岩在冻融循环作用下的损伤演化方程。同时,通过对饱和砂岩冻融循环过程中的物理性质的观测,及对砂岩自身结构特点的分析,选取砂岩的开孔隙率作为损伤变量。之后通过试验数据对所建立的损伤模型进行验证,并探讨损伤方程中各参数的确定方法。经过验证,该损伤模型能较好地反映饱和砂岩在冻融循环作用下的损伤扩展规律,可以为相关的研究提供参考。
Freeze-thaw cycles applying to saturated sandstone are considered as a kind of low frequency fatigue load after the analysis of its features. And the stress condition of sandstone under freeze-thaw cycles can be simplified to cycles of uniaxial tension. According to the above analysis,damage evolution equation is established based on the fatigue damage theory. Then,the open porosity of sandstone which has been tested during the freeze-thaw experiment is selected as the damage variable. After that,the new damage evolution model is tested and verified by the comparison between experiment data and theoretical value,and how to get the values of parameters in the equation is also discussed. The new model is proved to be able to describe the basic damage evolution law of sandstone,this could be the reference for similar researches.
出处
《岩石力学与工程学报》
EI
CAS
CSCD
北大核心
2013年第S2期3049-3055,共7页
Chinese Journal of Rock Mechanics and Engineering
基金
"十一五"国家科技支撑计划项目(2008BAC47B0X)
关键词
岩石力学
饱和砂岩
冻融循环作用
损伤模型
开孔隙率
rock mechanics
saturated sandstone
freeze-thaw cycles
damage evolution model
open porosity
