基于Drucker-Prager准则的岩石损伤本构模型

为解决用对数变换再线性拟合的方法求岩石损伤本构方程参数计算过程复杂、不利于计算机编程的问题,引入岩石应力-应变曲线特征参量,并考虑岩石应力-应变曲线的极值条件,给出了模型参数的解析式,从而建立了新的岩石损伤本构模型.通过与砂岩试件三轴压缩试验结果比较,证明所建立的模型可以很好地反映岩石的应力-应变关系.通过对参数m和F0的讨论,认为m和F0分别代表了岩石的脆性和强度,而弹性模量是参数m和F0的共同反映.

Damage Constitutive Model of Rock Based on Drucker-Prager Criterion

To overcome the shortcoming of the existing method to establish the damage constitutive model of rock,i.e.,it seeks parameters in the constitutive model by linear fitting after logarithmic transformation to result in a complex calculation and not to fit for computer programming,formulas of calculating the parameters in the constitutive model were given by introducing the characteristic parameters of the stress-strain curve of rock and taking the extreme conditions for the stress-strain curve of rock into consideration.As a result,a new constitutive damage model of rock can be easily established.Comparison with the result of triaxial compression tests shows that this model can reflect well the relationship between stress and strain of rock.Through a discussion on parameters m and F0 in the constitutive damage model,it is believed that m and F0 represent the brittleness and strength of rock respectively,and elastic modulus of rock is a co-reflection of the two parameters.