考虑加速蠕变的岩石蠕变过程损伤模拟方法

A Damage Simulation Technique of the Full Rock Creep Process Considering Accelerated Creep

针对岩石蠕变的阶段性特征,在深入研究岩石蠕变力学机理基础上,将岩石蠕变过程视为线性与非线性蠕变过程的迭加,通过引入损伤理论和Kachanov损伤演化规律,构建出可反映岩石非线性蠕变过程即加速蠕变过程特征的弹塑性损伤体元件模型,将其与可较好地反映岩石线性蠕变过程即减速蠕变过程特征的Kelvin元件模型进行串联复合,建立出可反映岩石蠕变全过程尤其是加速蠕变特点的岩石蠕变模型,并提出了简单可行的模型参数确定方法,从而建立出岩石蠕变全过程的新型模拟方法;该模型或方法不仅能较好地模拟岩石从减速到加速的蠕变全过程,而且,模型参数少,易于确定.最后,通过理论与实测曲线的对比分析,表明了该模型的合理性与可行性.

On the basis of the mechanism of rock creep, the rock creep process was regarded as the su- perposition of linear and nonlinear rock creep process according to its phase characteristic. An elastic-plas- ticity damage cell model, which can describe the nonlinear or accelerated rock creep process, was developed by introducing the damage theory and the law of damage proposed by Kachanov. Connected with Kelvin cell model, which can preferably simulate the linear or the decelerated rock creep process, a rock creep model reflecting the features of the full rock creep process was obtained. The accelerated rock creep process was established and its simple and feasible parameter determination method was put forward. A new technique simulating the full rock creep process was developed, which can simulate the rock deforma- tion process from decelerated to accelerated creep, and its parameters are few and easy to be determined. Finally, it shows that the model or technique proposed is reasonable and feasible after a comparison between the model and the experimental curves.