蠕变是岩石的一个重要力学特性,其变化特性影响着岩石工程结构长期的安全稳定性。为了研究钙芒硝的蠕变规律,在西原模型中引进一个随时间变化的粘性系数,建立了钙芒硝单轴、三轴蠕变模型。为了验证模型的准确性,进行了大量的蠕变试验,分析了载荷大小对蠕变三个阶段所经历时间的影响。利用Origin软件的自定义函数,结合单轴、三轴蠕变试验,拟合得出所建模型中的各个参数。拟合结果表明,所建蠕变模型能够较好的描述钙芒硝的单轴、三轴蠕变特性,且其单轴长期强度小于三轴长期强度。
As one of the most important mechanical properties of rocks,creep and its variation characteristics affect on the long-term security and stability of rock structures.In order to study the creep law of glauberite,a time-varying coefficient of viscosity was put forward in Nishihara model,and then an axial creep model and a triaxial creep model of glauberite were established.Moreover,some creep experiments were carried out to evaluate the accuracy of the proposed models,and creep duration of the three stages under different magnitude of load were analyzed.Combined with the results of the creep experiments,the parameters of the models were obtained by using self-defining function of Origin software.The results showed that the characteristics of axial creep and triaxial creep for glauberite can be well described by the fitting creep models,and the long-term strength of axis was less than triaxle.