Scaled experimental study on impulse wave generated by a typical semi-submerged landslide with a low Froude number in reservoir areas—Taking Wangjiashan landslide as an example
(1. Hubei Key Laboratory of Disaster Prevention and Mitigation,Yichang,Hubei 443002,China;2. College of Civil Engineering and Architecture,China Three Gorges University,Yichang,Hubei 443002,China;3. China Three Gorges Corporation,Chengdu,Sichuan 610000,China)
Abstract:Impulse wave generated by semi-submerged landslides in large reservoir mostly has a low Froude number,and its impact effect and wave characteristics need to be further revealed. Taking the Wangjiashan landslide of Baihetan reservoir as an example,a large-scale three-dimensional scaled landslide-induced impulse wave(LIW) experiment with the size of 30 m×27 m×1.5 m was constructed with a geometric scale of 1∶150,following the Froude similarity criterion. Nine groups of LIW experiments with Froude number of 0.08–0.32 were carried out to study the wave regularity of wading landslide under low Froude number. The research results show that as Fr≤0.15,the drag effect caused by the underwater motion is greater than the impact effect caused by the subaerial sliding mass at the beginning of motion,and the wave appears with a small trough at first. The type of primary wave generated by the landslide with a low Froude number is mostly transition wave. In the process of wave propagation,the wave type is easily transformed from the wave type with big translation capacity to that with low or non-translation capacity. The dimensionless wave amplitude and wave attenuation rate are linear and logarithmic functions with Froude number,respectively. Wave making efficiency of wading landslide with a low Froude number is lower than that of subaerial landslide with a high Froude number. The increase of the Froude number will lead to the strongly expansion of the hazard zone of impulse wave,and the increased red warning area multiple is about 10 times that of the increase of Froude number. These new understandings revealed the concealment and hazardous of LIW in the reservoir,supporting prevention and mitigation of impulse waves in the reservoir area.
黄波林1,2,胡刘洋1,2,李仁江3,胡 雷1,2,陈云飞1,2,胡 斌3,张 鹏1,2,秦 臻1,2,董星辰1,2. 水库区低Froude数的典型涉水滑坡涌浪缩尺物理模型试验研究——以王家山滑坡为例[J]. 岩石力学与工程学报, 2023, 42(8): 1899-1909.
HUANG Bolin1,2,HU Liuyang1,2,LI Renjiang3,HU Lei1,2,CHEN Yunfei1,2,HU Bin3,ZHANG Peng1,2,QIN Zhen1,2,DONG Xingchen1,2. Scaled experimental study on impulse wave generated by a typical semi-submerged landslide with a low Froude number in reservoir areas—Taking Wangjiashan landslide as an example. , 2023, 42(8): 1899-1909.
[1] HUANG B L,YIN Y P,CHEN X T,et al. Analysis of waves generated by Gongjiafang landslide in Wu Gorge,three Gorges reservoir,on November 23,2008[J]. Landslides,2012,(9):395–405.
[2] XIAO L L,STEVEN N W,WANG J J. Tsunami Squares approach to landslide generated waves:application to Gongjiafang landslide,Three Gorges Reservoir,China[J]. Pure and Applied Geophysics,2015,172(12):3 639–3 654.
[3] FRITZ H M,HAGER W H,MINOR H E. Landslide generated impulse waves-Instantaneous flow fields[J]. Experiments in Fluids,2003,35(6):505–519.
[4] FRITZ H M,HAGER W H,MINOR H E. Landslide generated impulse waves—2. Hydrodynamic impact craters[J]. Experiments in Fluids,2003,35(6):520–532.
[5] PANIZZO A,GIROLAMO P D,PETACCIA A . Forecasting impulse waves generated by subaerial landslides[J]. Journal of Geophysical Research,2005,110(C12):C12025.
[6] VALENTIN H,JOHANNES S. Improved landslide-tsunami prediction:effects of block model parameters and slide model[J]. Journal of Geophysical Research:Oceans,2013,118(3):1 489–1 507.
[7] BREGOLI F,BATEMAN A,MEDINA V. Tsunamis generated by fast granular landslides:3D experiments and empirical predictors[J]. Journal of Hydraulic Research,2017,55(6):743–758.
[8] LEE C H,HUANG Z. Effects of grain size on subaerial granular landslides and resulting impulse waves:experiment and multi-phase flow simulation[J]. Landslides,2022,19(1):137–153.
[9] RAUTER M,VIROULET S,GYLFADÓTTIR S S,et al. Granular porous landslide tsunami modelling – the 2014 Lake Askja flank collapse[J]. Nature Communications,2022,13(1):678.
[10] EVERS F M,HAGER W H,BOES R M. Spatial impulse wave generation and propagation[J]. Journal of Waterway,Port,Coastal and Ocean Engineering,2019,145(3):04019011.
[11] RISIO M D,GIROLAMO P D,BELLOTTI G,et al. Landslide-generated tsunamis runup at the coast of a conical island:new physical model experiments[J]. Journal of Geophysical Research:Oceans,2009,114(C1):1–16.
[12] MOHAMMED F,FRITZ H M. Physical modeling of tsunamis generated by three-dimensional deformable granular landslides[J]. Journal of Geophysical Research,2012,117(C11):C11015.
[13] 殷坤龙,刘艺梁,汪 洋,等. 三峡水库库岸滑坡涌浪物理模型试验[J]. 地球科学:中国地质大学学报,2012,37(5):1 067–1 074. (YIN Kunlong,LIU Yiliang,WANG Yang,et al. Physical model experiments of landslide-induced surge in Three Gorges Reservoir[J]. Earth Science-Journal of China University of Geoscience,2012,37(5):1 067–1 074.(in Chinese))
[14] HUANG B L,YIN Y P,WANG S C,et al. A physical similarity model of an impulsive wave generated by Gongjiafang landslide in Three Gorges Reservoir,China[J]. Landslides,2014,11(3):513–525.
[15] HELLER V,SPINNEKEN J. On the effect of the water body geometry on landslide-tsunamis:Physical insight from laboratory tests and 2D to 3D wave parameter transformation[J]. Coastal Engineering,2015,104(10):113–134.
[16] CHEN H Y,CUI P,CHEN X Q,et al. Laboratory experiments of water pressure loads acting on a downstream dam caused by ice avalanches[J]. Landslides,2015,12(6):1 131–1 138.
[17] EVERS F M,HAGER W H. Spatial impulse waves:wave height decay experiments at laboratory scale[J]. Landslides,2016,13(6):1–9.
[18] EVERS F M,HELLER V,FUCHS H,et al. Landslide generated impulse waves in reservoirs-Basics and computation[R]. [S. l.]:ETH- Zürich,Schweiz:VAW-Mitteilungen,2019:254.
[19] MCFALL B C,MOHAMMED F,FRITZ H M,et al. Laboratory experiments on three-dimensional deformable granular landslides on planar and conical slopes[J]. Landslides,2018,15(12):1 713–1 730.
[20] SAUTER E,FUCHS H,SCHMOCKER L,et al. Large-scale field tests on impulse waves[C]// 38th IAHR World Congress. Panama City:[s. n.],2019:727–739.
[21] KIM G B,CHENG W,SUNNY R C,et al. Three-dimensional landslide generated tsunamis:numerical and physical model comparisons[J]. Landslides,2020,17(5):1 145–1 161.
[22] HAN L,WANG P,MU P,et al. Experimental investigation of propagation and run-up of rockslide- generated impulse waves in a curved mountain reservoir[J]. Natural Hazards,2022,111(2):1 375–1 399.
[23] YAVARI-RAMSHE S,ATAIE-ASHTIANI B. Numerical modeling of subaerial and submarine landslide-generated tsunami waves-recent advances and future challenges[J]. Landslides,2016,13(6):1 325–1 368.
[24] YAVARI-RAMSHE S,ATAIE-ASHTIANI B. On the effects of landslide deformability and initial submergence on landslide-generated waves[J]. Landslides,2019,16(1):37–53.
[25] YI X Y,FENG W KI,WU M T,et al. The initial impoundment of the Baihetan reservoir region(China) exacerbated the deformation of the Wangjiashan landslide:characteristics and mechanism[J]. Landslides,2022,17(19):1 897–1 912.
[26] 郑文康,刘翰湘. 水力学[M]. 北京:中国水利水电出版社,1990:127–128.(ZHENG Wenkang,LIU Hanxiang. Hydraulics[M]. Beijing:China Water Power Press,Beijing,1990:127–128.(in Chinese))
[27] BREGOLI F,MEDINA V,BATEMAN A. The energy transfer from granular landslides to water bodies explained by a data-driven,physics-based numerical model[J]. Landslides,2021,18(4):1 337–1 348.
[28] ATAIE-ASHTIANI B,NAJAFI-JILANI A. Laboratory investigations on impulsive waves caused by underwater landslide[J]. Coastal Engineering,2008,55(12):989–1 004.
[29] ATAIE-ASHTIANI B,NIK-KHAH A. Impulsive waves caused by subaerial landslides[J]. Environmental Fluid Mechanics,2008,8(3):263–280.
[30] WALDER J S,WATTS P,OSCAR E S,et al. Water waves generated by subaerial mass flows[J]. Journal of Geophysical Research,2003,108(B5):2 236–2 255.
[31] FRITZ H M,HAGER W H,MINOR H E. Near field characteristics of landslide generated impulse waves[J]. Journal of Waterway Port Coastal and Ocean Engineering,2004,130(6):287–302.
[32] XUE H C,QIAN MA,DIAO M J,et al. Propagation characteristics of subaerial landslide-generated impulse waves[J]. Environmental Fluid Mechanics,2019,19(1):203–230.
[33] HELLER V,WILLI H,HANS-ERWIN M. Scale effects in subaerial landslide generated impulse waves[J]. Experiments in Fluids,2008,44(5):691–703.