中文摘要：

采用分级增量循环加卸载和单级加载方式，对金川有色金属公司Ⅲ矿区二辉橄榄岩试样进行弹黏塑性流变试验，在对流变试验数据进行深入分析基础上，详细研究该类岩石各蠕变阶段非线性黏弹塑性变形特性，将衰减蠕变曲线分离为黏弹性分量与黏塑性分量，研究各衰减蠕变变形分量的非线性特征，建立定常流动速率及加速蠕变率的应力、时间的拟合函数。根据不同应力水平下的加、卸载蠕变试验曲线，提出由瞬弹性Hooke体、黏弹塑性村山体、黏塑性改进Bingham体串联而成的新的岩石非线性弹黏塑性流变模型，对模型参数辩识，提出非线性元件参数的确定方法。该流变模型具有两个屈服极限且流变元件参数是关于应力和时间的拟合函数，考虑了衰减蠕变阶段和加速蠕变阶段的非线性特征，能反映不同应力水半下岩石流变规律，尤其能较合理地模拟岩石加速蠕变，从理论上给出非线性弹黏塑性流变模型的松驰方程和三维蠕变方程。利用不同应力水平下岩石蠕变全程试验曲线，对提出的非线性弹黏塑性流变模型进行充分验证。试验血线与非线性流变模型理论曲线较吻合，显示所建非线性弹黏塑性流变模型的正确性与合理性。

英文摘要：

A set of creep experiments were performed to study the elastovisco-plastic characteristics of iherzolite specimens in mining area III of Jinchuan Group Ltd. by the circular increment step load and unload method and single-stage loading method. Based on scientific analysis of experimental data, the nonlinear elastovisco-plastic deformation characteristics of this kind of rock were studied in detail. With the attenuation creep being divided into viscoelastic and viscoplastic portions, their nonlinear regression fitting functions were brought forward respectively. The fitting functions of steady creep rate and accelerative creep rate were built, in which stress σand time t were viewed as independent variables. According to loading and unloading creep test curves under different stress levels, by connecting the instantaneous elasticity Hooke body, viscoelasto-plastic Schiffman body and viscoplastic improved Bingham body in series, a new nonlinear elastovisco-plastic rheological model of rock was proposed. The method to confirm nonlinear parameters of components was proposed. The rheological model with two yield limitations were brought forward and the parameters of the components were nonlinear functions in which stress σ and time t were viewed as independent variables. So rheological model can reflect the rheological rules of rocks under different stress levels, especially it can simulate the accelerative creep. 3D creep and rheological equations under constant stress were deduced. On the basis of complete creep curves gained by RYL -600 rock servo-controlled rheology equipment, the identification of the proposed nonlinear elastovisco- plastic rheological model of rock is validated. The comparison between nonlinear rheological model and experimental curves show that two curves accord well each other, and the proposed nonlinear elastovisco-plastic rheological model is available and reasonable.