岩石材料的一种非线性三参数强度准则及应用  

A nonlinear tri-parameter strength criterion for rock materials and its application

作　　者：孔志鹏 孙海霞 陈四利 

机构地区：[1]沈阳工业大学建筑与土木工程学院,辽宁沈阳110187

出　　处：《岩土力学》2017年第12期3524-3531,共8页Rock and Soil Mechanics

基　　金：国家自然科学基金(No.51279109)~~

摘　　要：为了更好地描述岩石材料在多种复杂应力作用下的强度状态,在已提出的双T^2强度理论基础上,建立了一种新的非线性三参数强度准则。通过与Westerly花岗岩等5种岩石材料试验数据的比较,对准则在σ_1=σ_2>σ_3,σ_1>σ_2=σ_3,σ_3=0、σ_1>0、σ_2>0,σ_3>0和σ-τ 5种复杂应力状态下的合理性和适用性进行了讨论。研究表明:待定系数A、B、C可通过简单的试验确定且具有明确的物理意义;不同岩石材料的极限应力比α和β对应不同的强度理论;非线性三参数强度准则的π平面迹线介于单剪强度理论和Mises准则、双剪强度理论之间,符合各向同性材料屈服面三轴对称和外凸的公设;理论预测曲线可反映岩石材料中主应力效应的区间性与静水压力效应,并与多种岩石材料在复杂应力状态下的强度变化趋势基本吻合。To precisely describe the strength of rock materials under a variety of complex stress conditions, we developed a new nonlinear tri-parameter strength criterion based on the theory of twin T^2 strength. Compared with experimental results of five types of rock, the rationality and applicability of the proposed criterion were discussed separately under five stress states, i.e., σ_1σ_2 =σ_3,σ_1σ_2 =σ_3, σ_3=0 and σ_10, σ_20, σ_30 and σ-τ. The results shows that the parameters, A, B and C, can be determined by simple tests, though their physical meanings are reasonable. The different ultimate stress ratios α and β correspond to different strength theories. The limit line in the π plane of the proposed criterion is among the single shear strength theory, Mises criterion, and the twin shear strength theory. Furthermore, the criterion conform with the triaxial symmetry and the convexity of yield surface of the isotropic material. The theoretical prediction curve can reflect the interval characteristics of the principal stress and the hydrostatic pressure effect in rock materials. Moreover, it is in good agreement with the strength trends of some materials at complex stress states.

关 键 词：岩石 强度准则 双剪应力(T) 复杂应力状态 

分 类 号：TU443[建筑科学—岩土工程]