复杂应力路径下堆石料本构关系研究  

Study of constitutive relations of rockfill under complex stress path

作　　者：相彪[1] 张宗亮[2] 迟世春[1] 林皋[1] 

机构地区：[1]大连理工大学海岸与近海工程国家重点实验室,大连116024 [2]中国水电顾问集团昆明勘测设计研究院,昆明650051

出　　处：《岩土力学》2010年第6期1716-1722,1728,共8页Rock and Soil Mechanics

基　　金：国家自然科学基金项目(No.50879007;50979014)

摘　　要：已有研究表明,土石坝内堆石料在坝体填筑过程的应力路径可近似为等应力比的路径(q/p=常数),水库蓄水时应力路径将发生转折,呈复杂的应力路径形态(dq/dp=常数)。在大型三轴仪上进行了两种应力路径的排水试验,即等应力比路径下的偏压试验和复杂应力路径下的剪切试验。根据试验结果提出了一个堆石料应力路径增量非线性弹性模型,模型采用三模量形式除可以描述堆石料等应力比路径的应力-应变特征外,通过转折后的路径特征构造合适的柔度矩阵,能够表达转折应力路径下的本构关系。对试验曲线进行拟合表明,应力路径模型能够较好地反映堆石料在复杂应力路径下的应力与变形特性。Current research indicates that the stress path of rockfill during dam construction can be approximated as that the principal stress ratio keeps constant （q/p =constant）; and it will become a complex stress path （dq/dp =constant） upon reservoir filling. Drained tests were conducted in large scale triaxial apparatus under two types of stress path,which were the deviatoric compression tests under the paths of constant stress ratio and the shear tests under complex stress paths. According to the test results,an incrementally nonlinear elastic model of rockfill considering the effect of stress path was proposed,which including three modulus functions could describe not only the stress-strain characteristics of rockfill under constant stress ratio,but also the constitutive relations of transitional stress paths according to the appropriate compliance matrixes based on the transitional path feature. From the simulations of the test curves,it is shown that the model can well predict the stress and deformation behaviors of rockfill under complex stress paths.

关 键 词：等应力比 复杂应力路径 模量 本构关系 

分 类 号：TU411.3[建筑科学—岩土工程]