适用于节理岩体的新型黏弹塑性模型研究  

ANALYSIS OF A NEW VISCO-ELASTO-PLASTIC MODEL FOR JOINTED ROCK MASS

作　　者：张贵科[1] 徐卫亚[1] 

机构地区：[1]河海大学岩土工程研究所,江苏南京210098

出　　处：《岩石力学与工程学报》2006年第z1期2894-2901,共8页Chinese Journal of Rock Mechanics and Engineering

基　　金：国家重点基础研究发展规划(973)项目(2002CB412707);国家自然科学基金资助项目(50539110)

摘　　要：在分析岩体变形特点和常用流变模型变形特性的基础上,提出与应力状态和时间相关的非线性黏性体。非线性黏性体在应力小于其极限值时,变形随时间增长而趋于稳定,当应力大于其极限值时,变形将随时间增长而急剧增大。将非线性黏性体引入传统Maxwell模型中,由改进的Maxwell模型与传统Kelvin模型和St.Venant塑性体串联得到新型五元件黏弹塑性模型。在五元件黏弹塑性模型中,改进Maxwell体中的弹性体和非线性黏性体分别模拟瞬时弹性变形和黏性流动变形,Kelvin体和St.Venant体分别模拟延滞回复和瞬时塑性变形。理论分析和试验验证表明,五元件黏弹塑性模型可以较全面地反映岩体变形特征,并可以反映岩体在低应力状态下流变趋于稳定、而应力水平超过其极限值后出现加速流变而破坏的流变规律。On the basis of analyzing the characteristics of rock mass deformation and general rheological models,a new non linear viscous substance which is related to stress state and time is presented.When the stress is lower than its limit value,the deformation of the new nonlinear viscous substance will reach to the stable state as time going on,otherwise,the deformation will increase sharply.The new nonlinear viscous substance is applied to improve the function of the classical Maxwell model.A new visco-elasto-plastic constitutive model consisted of 5-components(VEP-5C model) is defined in series with the improved Maxwell model,the classical Kelvin model and the St.Venant plastic substance.The elastic component and the non-linear viscous component of the improved Maxwell model can simulate the instantaneous elastic deformation and visco-plastic deformation respectively.The Kelvin model and St.Venant component of VEP-5C model can represent the visco-elastic deformation and instantaneous plastic deformation respectively.Theoretical analysis and results of test indicate that the new 5-components visco-elasto-plastic constitutive model can fully describe the characteristics of rock mass deformation.The new model can also characterize the property that the rock mass rheological deformation will keep stable in lower stress state,while accelerating rheological deformation in stress exceeding its limit.

关 键 词：岩石力学 节理岩体 岩体变形 流变模型 非线性黏性体 黏弹塑性模型 

分 类 号：TU457[建筑科学—岩土工程]