论文部分内容阅读
提出了Davidenkov本构模型的不规则加卸载修正准则,以代替扩展Masing法则中的“上大圈”准则,并通过南京细砂原状土样的共振柱试验,提出了考虑初始有效围压对初始剪切模量和参考剪应变的修正公式.利用ABAQUS显式开发模块,实现了基于不规则加卸载准则的修正Davidenkov本构模型与Byrne孔压增量模型的有效应力算法.对饱和南京细砂进行排水循环三轴试验,给出了南京细砂的Byrne孔压增量模型参数;对饱和南京细砂进行了不排水循环三轴试验和三维数值仿真的比较研究,发现该子程序能够较好地模拟南京细砂的振动孔压发展过程,合理地反映土体的液化特性,从而验证了本文提出的有效应力算法的合理性.
This paper proposes an irregular loading-unloading correction criterion of Davidenkov’s constitutive model instead of extending the “large circle” criterion in Masing’s law. Based on the resonant cylinder test of the fine sand-like soil in Nanjing, The formulas for correcting the initial shear modulus and the reference shear strain are also given.The effective stress algorithm of modified Davidenkov constitutive model and Byrne pore pressure increment model based on irregular loading and unloading criterion is realized by using ABAQUS explicit development module.For saturated Nanjing The fine sand is drained and circulated in triaxial test, and the Byrne pore pressure increment model parameters of Nanjing fine sand are given. The comparative study of undrained cyclic triaxial test and three-dimensional numerical simulation of saturated fine sand shows that this subroutine can It can well simulate the development process of vibrating pore pressure of fine sand in Nanjing and reasonably reflect the liquefaction characteristics of soil so as to verify the rationality of the effective stress algorithm proposed in this paper.