摘要
冻融交替对岩石宏观强度产生弱化。基于冻融循环条件下的压缩试验结果,利用损伤力学研究材料强度特征及损伤演化,建立岩土材料的损伤模型。结果表明:随着循环次数的增加,砂岩的力学强度参数均逐渐减小,抗压强度与弹性模量的降低幅度可以达到49.70%、83.40%,意味着冻融循环对材料力学性质损伤显著;定义岩石综合损伤变量,得到损伤演化特征曲线,基于高斯函数变化特征,构建冻融循环条件下材料损伤本构模型,对比分析试验与模型曲线,发现该模型能够较好地描述试验结果。基于高斯函数的损伤模型能较好地反映材料变形行为特征,研究成果可以为类似本构模型的建立提供参考。
Freeze-thaw alternation weakens the macroscopic strength of rocks.Based on compression test results under freeze-thaw cycles,this work used damage strength to study material strength characteristics and damage evolution,and established the material damage model under freeze-thaw cycles.The results show that with the increasing number of cycles,the mechanical strength parameters of sandstone are gradually reduced,and the reduction range of comprehensive strength and elastic modulus can reach 49.70%and 83.40%,respectively.It is indicated that the freeze-thaw cycle damages the mechanical properties of the material significantly.The comprehensive damage variable of rock was defined,and the damage evolution characteristic curve was obtained.Based on the characteristics of Gaussian function,the damage constitutive model of the material under freeze-thaw cycles was constructed.Compared the experimental results with the model curves,the model can well describe the experiment results.The damage model based on Gaussian function can better reflect the deformation behavior of materials,and the research results can provide reference for the establishment of similar material constitutive models.
作者
杨涛
霍树义
金坎辉
穆琳
周晴晴
崔建军
YANG Tao;HUO Shuyi;JIN Kanhui;MU Lin;ZHOU Qingqing;CUI Jianjun(Hebei University of Water Resources and Electric Power,Cangzhou,Hebei 061001)
出处
《地质与勘探》
CAS
CSCD
北大核心
2020年第4期826-831,共6页
Geology and Exploration
关键词
冻融循环
损伤变量
损伤演化
本构模型
freeze-thaw cycles
damage variable
damage evolution
constitutive model
