岩石试件非线性蠕变模型及其稳定性分析

NON-LINEAR CREEP MODEL AND STABILITY ANALYSIS OF ROCK

以改进的西原正夫模型为基础,利用岩石全过程应力-应变曲线与蠕变方程中参数的对应关系,建立参数非线性蠕变模型。通过对非线性蠕变模型和蠕变曲线的分析,把非线性蠕变问题通过局部线性化,得出了改进的西原正夫模型的稳定性条件,较好地反映了岩石试件的3阶段蠕变过程,尤其是非线性加速蠕变变形;同时,得出岩石试件蠕变稳定性的判别准则和蠕变变形、蠕变速率和蠕变加速度的解析表达式。

Based on the modified elastic and visco-elasto-plastic model, the corresponding relationship of complete rock stress-strain curve and creep equation parameters is utilized, and a creep model with non-linear parameters is set up. By analyzing non-linear creep model and the creep curve, in the local scope, non-linear creep question is transferred into linear one, and the stability condition of the modified model is obtained, with which the three stages of rock sample creep, especially the non-linear accelerating creep stage can be described clearly, Meantime, the creep stability criteria of rock sample, analytic expressions of the creep deformation, the creep speed and the creep acceleration are given.