爬行着的山体滑坡的疲劳减弱是由多级降雨造成的
Hui Wang1, Qingwen Yang2, Xiangjun Pei1
1State Key Laboratory of Geohazard Prevention and Geoenvironment Protection, Chengdu University of Technology, Chengdu, 610059, China.
Scientific reports
|July 15, 2025
概括
多级降雨在山体滑坡中造成累积损害,加速它们的进展到失败. 了解这种疲劳减弱对于预测和减轻山体滑坡风险至关重要.
科学领域:
- 地质技术工程 地质技术工程
- 地球科学 地球科学 地球科学
- 地质形态学 地质形态学
背景情况:
- 大规模的山体滑坡是一个重要的地质危险,由于多级降雨的累积损害,在长时间内发展.
- 这些山体滑坡对人类生命和基础设施构成重大风险,灾难性故障发生在初始损坏数月或数年后.
- 在反复降雨事件下疲劳减弱过程是滑坡演变的关键因素.
研究的目的:
- 为了研究大型爬行滑坡的疲劳减弱机制,这些滑坡受到多级降雨的影响.
- 用创新的实验方法分析多阶段降雨模式和山体滑坡变形之间的相关性.
- 了解降雨对滑坡剪切区材料的累积破坏性影响.
主要方法:
- 设计和实施新的降雨级爬行实验.
- 使用来自大规模爬行滑坡的剪切区域材料.
- 在受控的多阶段降雨和应力条件下监测孔隙水压和变形.
主要成果:
- 每一次降雨事件都会导致孔隙水压的快速增加,导致短期变形加速,随后是稳定状态的爬行.
- 降雨频率的增加减少了故障所需的事件数量,缩短了二级爬行持续时间,加速了三级爬行.
- 较低的应力水平,在相同的降雨下,显著延长了二次爬行,但导致了较早的故障,突出了材料对降雨的敏感性.
结论:
- 多级降雨对山体滑坡剪切区材料产生累积的破坏性影响,逐渐削弱它们.
- 降雨级爬行实验为现场滑坡的行为提供了定量见解,将爬行与最终的故障联系起来.
- 这项研究增强了对循环水文负载下大规模滑坡中疲劳和故障过程的理解.
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