摘要
为描述岩石完整蠕变特性,基于非线性流变力学理论,引入能够描述衰减蠕变和加速蠕变阶段的2个非线性函数,将替换传统Bingham模型中的线性元件,建立了一种改进后的Bingham岩石蠕变本构模型。通过引入屈服强度阀值来界定岩石蠕变阶段,当岩石在高应力状态下,模型能同时描述衰减蠕变、定常蠕变和加速蠕变3个阶段。利用天然页岩蠕变试验结果,根据通用全局优化算法,对改进后Bingham模型的参数进行反演辨识,获得了流变参数。对比拟合曲线与试验结果显示,改进后的模型拟合效果良好,相关系数均在0.9以上,说明该模型的适用性与可行性。
In order to describe the complete creep properties of rock, an improved Bingham rock creep constitutive model is established based on nonlinear rheological mechanics theory, in which, two nonlinear functions that can describe attenuation creep and accelerated creep stages respectively are introduced to replace the traditional linear elements in Bingham model. The yield strength threshold is also introduced to define the stage of rock creep. When the rock is in the condition of high stress, the model can describe three stages of attenuation creep, steady creep and accelerated creep simultaneously. Based on the creep test results of natural shale, the parameters of improved Bingham model are identified by inversion according to general global optimization algorithm, and the rheological parameters are obtained. The comparison between fitting curve and experimental results shows that the improved model has good fitting effect and the correlation coefficient is more than 0.9. The model has good applicability and feasibility.
作者
王唯
刘远明
WANG Wei;LIU Yuanming(Civil Engineering College, Guizhou University, Guiyang 550025, Guizhou, China)
出处
《水力发电》
北大核心
2019年第8期18-22,41,共6页
Water Power
基金
国家自然科学基金资助项目(11562005)
