Xiang Bo, Liu Enlong, Yang Liuxin
Sichuan Provincial Transport Department Highway Planning, Survey, Design and Research Institute, Chengdu, 610041, Sichuan, China.
State Key Laboratory of Hydraulics and Mountain River Engineering, College of Water Resources and Hydropower, Sichuan University, Chengdu, 610065, China.
Sci Rep. 2022 Mar 30;12(1):5387. doi: 10.1038/s41598-022-09379-3.
Freezing-thawing actions can affect the mechanical features of soil greatly, which is vital for the stability of soil slope in cold regions. Firstly, triaxial compression tests on sand samples under undrained conditions were performed to investigate the influences of freezing-thawing cycles, which shows that the freezing-thawing actions can weaken their strength and stiffness, and with the increasing freezing-thawing cycles, both the deviatoric stress and pore water pressure decrease gradually. Then, the double hardening constitutive model was revised to model the influences of freezing-thawing cycles in consideration of the influences of freezing-thawing actions, and the model was also validated by the test results. Finally, the proposed constitutive model was incorporated into a finite element code to numerically simulate the distribution of displacement and pore water pressure of sand slope subjected to freezing-thawing cycles, which shows that the freezing-thawing actions accelerate the dissipation of the pore water pressure and enlarge the displacement of the slope. The study here can provide a help in designing and construction of civil engineering in cold regions.
冻融作用会对土壤的力学特性产生很大影响，这对寒冷地区土坡的稳定性至关重要。首先，进行了不排水条件下砂土试样的三轴压缩试验，以研究冻融循环的影响，结果表明冻融作用会削弱其强度和刚度，并且随着冻融循环次数的增加，偏应力和孔隙水压力均逐渐降低。然后，考虑冻融作用的影响，对双硬化本构模型进行修正以模拟冻融循环的影响，该模型也通过试验结果得到了验证。最后，将所提出的本构模型纳入有限元程序中，对经历冻融循环的砂土边坡的位移和孔隙水压力分布进行数值模拟，结果表明冻融作用加速了孔隙水压力的消散并增大了边坡的位移。本文的研究可为寒冷地区土木工程的设计与施工提供帮助。
