涌浪规模对冰碛湖溃决的影响实验  

An Experiment of the Effects of Waves on Glacial Lake Outburst Induced by Waves Overtopping

作　　者：黄金辉[1,2] 刘建康[1,2] 程尊兰[1] 张小刚[1] 刘大翔[1,2] 赵鑫[1,2] 

机构地区：[1]中国科学院成都山地灾害与环境研究所/中国科学院山地灾害与地表过程重点实验室四川成都610041 [2]中国科学院大学北京100049

出　　处：《山地学报》2014年第2期241-248,共8页Mountain Research

基　　金：国家科技支撑计划项目(2012BAK10B02-4);交通运输部科技项目(201231879210);中交股份科技研发项目(2011-ZJKJ-04)~~

摘　　要：随着全球气候变暖,冰碛湖溃决灾害频发,冰碛湖溃决的触发机理研究成为关注点,其中由于冰(雪)崩坠湖触发的涌浪冲蚀破坏是冰碛湖溃决的主要因素。为探索研究涌浪诱发冰湖溃决的动力过程,设计了一套水槽系统进行模拟实验,探讨冰(雪)崩塌入湖诱发涌浪溃坝的发展过程及溃决流量特征,分析不同涌浪规模对溃坝形成机制的影响。结果表明:1.涌浪是冰碛湖坝体溃决的直接触发因素,在首浪及后续周期性折返涌浪的作用下坝体溃口逐渐形成,其后随着水势能增大,在下蚀、溯源侵蚀和侧蚀的共同作用下,坝体侵蚀率迅速加大,洪峰流量出现在这个阶段;2.涌浪规模越大,首浪对坝顶的侵蚀越充分,涌浪对坝体的侵蚀越迅速,坝体剖面形态线越稀疏。由于静水位不变条件下侧蚀作用更强烈,溃口的最终宽度较静水位改变的情形大;3.静水位改变的情形下,首浪漫溢形成极大规模的初始流量Q0,并且首浪规模越大,初始流量Q0也就越大。洪峰流量Qm出现在坝体溃决初期,涌浪规模越大,洪峰流量Qm出现时间越早。As a result of recent climate warming,GLOFs become more frequently.More and more researchers focus on the mechanism of GLOFs,and find most of GLOFs are initiated by waves from ice avalanches that collapse into lakes.Under laboratory conditions,this paper studies the development and characteristics of dam failure caused by waves and focuses upon the effects of the different scales of waves on dam failure.Conclusions as followed：1.Waves overtopping and erosion result in dam failure,and the breach gradually forms in the wake of the initial wave and the following waves.With the interaction of incision,lateral erosion and retrogressive erosion,the erosion rate increases and peak discharge emerges.2.The lager the waves,the more the initial wave erodes dam crest,the higher the dam erosion rate,the thinner the instant profiles of dam every 1 second.Due to the higher rate of lateral erosion on the condition of static water level,the breach is wider than the dynamic one.3.Under the condition of static water level,the first wave overtopping forms the initial discharge Q0,and the larger the waves,the larger the initial discharge Q0.Peak discharge Qmappears at the beginning of the dam failure,Qmforms earlier when the waves are larger.

关 键 词：涌浪 冰碛湖 冰碛湖溃决 实验研究 

分 类 号：P694[天文地球—地质学]