循环荷载下裂隙岩体的改进分数阶西原模型  

Study on the Modified Nishihara Model based on Fractional Calculus Theory of Rock Masses under Cyclic Loading

作　　者：王勇 杜伟 WANG Yong;DU Wei(School of Civil Engineering,Wuhan University,Wuhan 430072,China;Sichuan Mianjiu Expressway Co.,Ltd.,Jiangyou 621700,China)

机构地区：[1]武汉大学土木建筑工程学院,湖北武汉430072 [2]四川绵九高速公路有限责任公司,四川江油621700

出　　处：《粉煤灰综合利用》2021年第2期13-19,42,共8页Fly Ash Comprehensive Utilization

基　　金：国家自然科学基金重点项目(51839009)。

摘　　要：为了探究在循环荷载下岩石的疲劳变形特性,本文基于分数阶微积分构建了非定常疲劳分数阶黏塑性体,利用其替换传统西原模型中的黏塑性体,然后对引入的裂隙塑性体进行改进。最后,将非定常疲劳分数阶黏塑性体、改进的裂隙塑性体与广义Kelvin体串联,构建了一维和三维新型分数阶黏弹塑性体疲劳本构模型。对已有的岩石疲劳试验结果拟合表明:经过改进后的西原模型,对于循环荷载下的减速、等速以及加速3个岩石疲劳变形的阶段可以较好地描述,同时也较好体现了循环荷载下裂隙对岩石变形的影响。In order to study the fatigue deformation characteristics of rock under cyclic loading,a non-definite fatigue fractional visco-plastic element was constructed based on fractional calculus theory. Firstly,the visco-plastic body in the classical Nishihara model was replaced by a non-definite fatigue fractional visco-plastic element. Then the fractured plastic element was introduced and modified. Finally,the modified fractured plastic element and a non-definite fatigue fractional visco-plastic element were connected in series with the generalised Kelvin model,1D and 3D new fractional viscoelastic-plastic fatigue constitutive models,which can describe the law of rock deformation under cyclic loading were established. The fitting of the previous rock fatigue test results shows that the modified Nishihara model can well describe the three fatigue deformation stages of deceleration,constant velocity,and acceleration under cyclic loading. At the same time,it also well reflects the influence of joints and cracks on rock deformation under cyclic loading.

关 键 词：岩石力学 循环荷载 非定常疲劳分数阶黏塑性体 裂隙塑性体 

分 类 号：TU459[建筑科学—岩土工程]