冰滑坡涌浪下冰碛坝溃决机理试验研究
作者:
作者单位:

作者简介:

通讯作者:

中图分类号:

P642.23

基金项目:

中国科学院前沿科学重点研究项目(QYZDY-SSW-DQC006);国家自然科学基金项目(41731283;41771045);中科院创新促进会(2017425);中国科学院“西部之光”人才培养计划项目


Experimental Study on Mechanism of Moraine Dam Failure Due to Surge Wave of Glacier Avalanches
Author:
Affiliation:

Fund Project:

  • 摘要
  • |
  • 图/表
  • |
  • 访问统计
  • |
  • 参考文献
  • |
  • 相似文献
  • |
  • 引证文献
  • |
  • 资源附件
  • |
  • 文章评论
    摘要:

    [目的] 对冰滑坡涌浪导致的冰碛坝溃决过程与溃决机理进行试验研究,为冰川区重大工程建设和冰湖冰碛坝溃决灾害防治提供科技支撑。[方法] 开展不同滑块体积、滑动角度、滑动距离、坝体物质组成和坝体几何形态的水槽模型试验。基于试验现象、试验数据与理论推导,对涌浪过程、坝体物质起动和坝体溃决临界条件进行分析。[结果] ①冰滑坡涌浪随时间和距离不断衰减,其随时间衰减显著。②将涌浪作用下的溃决过程分为坡面侵蚀、陡坎侵蚀、侧向侵蚀和衰退4个阶段,其中侧向侵蚀阶段的溃决流量最大,流速最快,侵蚀能力最强。③从颗粒起动机理的角度给出了颗粒起动流速,与沙莫夫公式进行对比分析,对比结果较为吻合。④基于能量守恒原理得到了冰湖溃决事件发生的临界条件,通过西藏自治区林芝市波密县米堆沟光谢错冰湖溃决事件进行验证,验证结果良好。[结论] 冰湖库容越大、坝前水深越深、涌浪高度越高,坝体越易发生溃决;冰碛坝堆积物中细颗粒含量越高,坝体颗粒间黏附力越强,坝体越稳定;冰碛坝坝宽及下游坡脚越大,坝体越稳定,溃决所需时间越长。

    Abstract:

    [Objective] The process and outburst mechanism of moraine dam failure caused by glacier avalanches were studied, in order to provide scientific support for major engineering construction in glacial areas and disaster prevention of glacier lake outburst.[Methods] The model test in flume was carried out with the different volumes of blocks, sliding angle, sliding distance, composition materials and geometric morphology of the dam body. Based on the experimental phenomena, experimental data and theoretical derivation, the process of the surge, the starting mechanism of dam body materials, and the critical condition of outbursts was analyzed.[Results] ① The surge of glacier avalanches decreased with time and distance, and the attenuation was significant with time. ② The outburst process under the surge could be divided into four stages:slope surface erosion, scarp erosion, lateral erosion, and decline. The lateral erosion stage had the largest outburst discharge, the fastest velocity, and the strongest erosion capacity. ③ The starting velocity of particles was given from the perspective of the particle starting mechanism, and the results were in good agreement with that of the Shamov formula. ④ It was verified by the outburst event of Guangxiecuo ice-lake breach in Midui gully, in Bomi County, Linzhi City, Tibet Autonomous Region, and the result is reasonable.[Conclusion] The larger the ice lake storage capacity, the deeper the water depth in front of the dam, the higher the water level rise caused by a glacial landslide, and the more likely the dam body is to outburst. The higher the content of the fine particles in the accumulation of the moraine dam, the stronger the adhesion between the particles, and the more stable the dam body is. The wider the moraine dam and the lower slope foot are, the more stable the dam body is, and the longer the outburst time is.

    参考文献
    相似文献
    引证文献
引用本文

李慧斌,陈华勇,Robin Neupane,阮合春,李霄.冰滑坡涌浪下冰碛坝溃决机理试验研究[J].水土保持通报,2021,41(2):25-34,42

复制
分享
文章指标
  • 点击次数:
  • 下载次数:
  • HTML阅读次数:
  • 引用次数:
历史
  • 收稿日期:2020-10-08
  • 最后修改日期:2020-12-08
  • 录用日期:
  • 在线发布日期: 2021-05-21
  • 出版日期: