【作者】 李平恩； 殷有泉；

【Author】 LI Ping’en~1,YIN Youquan~2 (1.Institute of Geophysics,China Earthquake Administration,Beijing 100081,China; 2.Department of Mechanics and Engineering Science,Peking University,Beijing 100871,China)

【机构】 中国地震局地球物理研究所； 北京大学力学与工程科学系；

【摘要】 针对在岩石塑性力学领域广泛应用的Drucker-Prager准则(简称D-P准则)是一个压剪屈服准则,在拉剪受力状态下不适用的情况,提出在拉剪区修正D-P准则的2种可行性方案。第一种方案是在压剪区,仍采用D-P准则的锥面式,而在拉剪区及其邻近,采用一个球形屈服面代替原来的锥顶附近的锥面。第二种方案是使用一个双曲旋转面近似地代替D-P圆锥面。将这2种方法定义的新的修正的D-P准则简称为D-P-Y准则,它是一个三参数准则,不仅在压剪区符合三轴压缩实验结果,而且在拉剪区也可拟合抗拉强度的资料。同时,它还是一个在全区域处处光滑的正则函数,可以使用经典的正交法则和一致性条件建立本构关系,而不必做任何奇异点的处理,这给应用和编程都带来方便,具有广泛的应用前景。特别地,对于双曲型的D-P-Y准则,当相关参数取0时,可分别退化为D-P准则和Mises准则,因此,在编程中可只编入D-P-Y准则。更多还原

【Abstract】 Drucker-Prager criterion(D-P criterion) has been widely used in the field of rock plastic mechanics. However,it is a type of compression shear yield criteria and not suitable for tensile shear stress states.According to this case,two feasible schemes are proposed to modify D-P criterion in tensile shear region.The first scheme is that the conical surface expression is still retained in compression shear region while in tensile shear region and its neighbor,a spherical yield surface is employed in place of the original conical surface near cone apex.The second scheme uses a hyperbolic rotating surface to approximately replace D-P conical surface.The modified new criteria defined by the two methods are called as D-P-Y criterions.They are three-parameter criteria and not only agree with the experimental result in triaxial compression test in compression shear stress states,but also can fit the tensile strength date in tensile shear regions.Meanwhile,the D-P-Y criteria are everywhere-smooth regular functions in all compression shear and tensile shear regions,and the constitutive equations can be established by using classic normality rule as well as consistency condition,needing no treating any singular points specially, which brings conveniences for application and programming.Particularly,for hyperbolic type D-P-Y criterion,when the relevant parameters are zero,it can be degenerated into D-P and Mises criterion,respectively.Therefore,it can be incorporated into D-P-Y criterion only in programming.更多还原