基于多元线性回归模型的冻土强度影响因素 显著性分析

To quantitative analyze the impact of soil type, moisture content, temperature and strain rate, etc. on strength of frozen soil, a significance analysis of influence factors on strength of frozen soil was carried out with multiple linear regression models based on the published experimental data in this study. The results show that the main factors influencing the strength of frozen soil are temperature and soil property, with the impact intensity of 0.632 and 0.193 , respectively, when considering linear effect only. Moisture content also has significant effect with the intensity of -0.577. In order to investigate the nonlinear effect of the impact factors on strength of fro¬zen soil, the nonlinear term is linearized by variable substitution under the condition of retaining second order of Taylor expansion of strength, and the multiple linear regression model is used to analyze furtherly. The analytical results show that the impacts of moisture content and temperature on the strength of frozen soil include linear, nonlinear and cross impacts, while the strain rate on strength contains only nonlinear and cross impacts. The im¬pact intensity of the factors on the strength of frozen soil could be quantitatively described by partial regression coefficient.