【摘要】 经典西原流变模型能够较好地描述岩石材料蠕变过程的前两个阶段,但不能描述加速蠕变阶段。前人对流变模型的改进和组合多以屈服强度阀值来界定加速蠕变阶段,而以时间阀值来界定加速蠕变阶段的研究相对较少。本文引入能反映加速蠕变加载时间的时间元件和能够描述加速蠕变曲线的非线性黏壶,两者并联组成TN体再与传统西原模型进行组合,形成一种能同时描述衰减蠕变、定常蠕变、加速蠕变的非线性黏弹塑性流变模型。并将新模型与实际试验数据进行拟合,相似性系数达0.99以上,所得模型更适合描述岩石材料的流变现象。更多还原

【Abstract】 The classic Nishihara rheological model can better describe the former two stages of creep process of rock,but can’t describe the accelerated creep stage.The most of predecessors made yield strength threshold to define the accelerated creep stage in the rheological model improvement and combination,but the researches on using time threshold to define the accelerated creep stage were relatively few.In this paper a time element which can reflect the accelerated creep loading time and a nonlinear clay pot which can describe the accelerated creep curve are introduced.Their parallel connection called TN combined with traditional Nishihara model,formed a nonlinear viscoelastic-plasticity rheological model that can describe the attenuation creep,steady creep and accelerated creep.Finally,fitting the new model and the actual experimental data,the similarity coefficient is higher than 0.99.The model is more suitable to describe the rock rheological phenomenon.更多还原