Seasonal differences in seismic responses of embankment on a sloping ground in permafrost regions
Seasonal differences in seismic responses of embankment on a sloping ground in permafrost regions
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多年冻土区坡地路堤地震响应的季节差异
DOI：
10.1016/j.soildyn.2015.01.005
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发表时间：
2015
影响因子：
4
通讯作者：
Yu Wenbing
中科院分区：
文献类型：
--
作者：
Li Shuangyang;Lai Yuanming;Zhang Mingyi;Yu Wenbing
由于温度直接影响冻土中未冻水的量和粒间冰的强度，因此温度对活动层的力学行为的各个方面都有显著影响，其中温度在0 °C上下波动。因此，多年冻土区斜坡路基等工程结构的地震反应随季节变化表现出明显的差异。为研究多年冻土区斜坡路基的地震特性，基于传热学、土壤水分动力学、冻土力学、土壤动力学、等等。青海一处监测良好的坡地铁路路堤--以青藏高原为例，模拟了第25服务年四个典型季节的地震反应。结果表明，地震加速度、速度和位移响应在四个典型季节有显著差异，其中10月15日的地震响应最大。地震结束后，路堤仍存在永久性差异变形，10月15日左侧边坡破坏严重。因此，应密切监视并及时修复该位置，以确保安全运行。此外，本文的数值模型和计算结果可为多年冻土区其他路基的养护、设计和研究提供参考。
Because of its direct influence on the amount of unfrozen water and on the strength of intergranular ice in a frozen soil, temperature has a significant effect on all aspects of the mechanical behavior of the active layer in which temperature fluctuates above and below 0 °C. Hence seismic responses of engineering structures such as embankment on a sloping ground in permafrost regions exhibit obvious differences with seasonal alternation. To explore the distinctive seismic characteristics of a railway embankment on the sloping ground in permafrost regions, a coupled water-heat-dynamics model is built based on theories of heat transfer, soil moisture dynamics, frozen soil mechanics, soil dynamics, and so on. A well-monitored railway embankment on a sloping ground in Qinghai–Tibet Plateau is taken as an example to simulate seismic responses in four typical seasons in the 25th service year. The numerical results show that seismic acceleration, velocity and displacement responses are significantly different in four typical seasons, and the responses on October 15 are much higher among the four seasons. When the earthquake is over, there are still permanent differential deformations in the embankment and even severe damages on the left slope on October 15. Therefore, this position should be monitored closely and repaired timely to ensure safe operation. In addition, the numerical model and results may be a reference for maintenance, design and study on other embankments in permafrost regions.