冻结砂岩单轴抗压应力应变复合幂指数模型

Uniaxial Compressive Stress-Strain Composite Exponential Model of Frozen Sandstone

为研究冻结砂岩应力应变关系,以内蒙古原状砂岩为试验对象,采用WDT-100冻土单轴试验压缩机开展了不同温度状态下冻结砂岩单轴抗压强度试验,得到应力应变曲线并分析试验结果。基于复合幂指数非线性理论进行曲线拟合,得出不同冻结温度下模型的参数方程。考虑温度因素的影响,改进复合幂指数非线性模型,提出一个与冻结温度有关的新型复合幂指数应力应变模型,将理论曲线与试验结果进行对比,发现拟合情况较好,显示了所建模型的合理性。

In order to study the stress-strain relationship of frozen sandstones, the intact sandstone in Inner Mongolia was used as the test object. Uniaxial compressive strength tests of frozen sandstone at different temperatures were carried out by WDT-100 frozen soil uniaxial compressors. The stress-strain curves were obtained and analyzed result. Based on the compound power exponent nonlinear theory curve fitting, the parametric equations of the model under different freezing temperatures are obtained.Considering the influence of temperature, the nonlinear model of composite exponential is improved,and a new composite exponential stress-strain model is established, which is related to the freezing temperature. Comparing the theoretical curve with the experimental results, it is found that the fitted model is in good agreement with the experimental results.