| The huge waves disaster caused by landslides is a common natural disaster phenomenon,often occurring in reservoir areas or large river channels.Rainfall,earthquakes,and other factors can cause geological instability of bank slopes to slide,including landslides,rockfalls,avalanches,and glacier collapses on the slopes,resulting in huge surges in open oceans,bays,natural lakes,and reservoirs.When landslides enter the water at a high sliding speed,The huge surge generated will pose a great threat to surrounding residents,coastal buildings,and upstream and downstream buildings.On a global scale,hundreds of deaths are caused by natural disasters such as landslides and swells every year.One of the most serious landslide and surge disasters in history was the Vaj ont Reservoir in northeastern Italy in 1963.After the surge overflowed,the dam broke,causing floods that destroyed several villages downstream,resulting in approximately 2000 deaths.At present,more than 500 medium to large reservoirs have been constructed nationwide,and many reservoirs under construction are about to be put into operation.Landslides and secondary surge disasters seriously threaten the safe operation of these reservoirs and the safety of dam bodies[3].Surge waves that cross dams may pose a threat to residents and buildings along the coast,upstream and downstream[2].The study of surge wave climbing can provide effective technical support for the early warning of reservoir landslide disasters,and has significant promotion and application value,which is of great significance for the prevention and control of landslide surge disasters.The main research content and conclusions of this article are as follows:(1)We conducted a two-dimensional flume experiment on landslide surge waves,studied the effects of factors such as landslide type and size on the characteristics of generated surge waves,studied the climbing behavior of different types of surge waves on slopes,and analyzed the types of breaking of surge waves after climbing,as well as the effects of different factors on the climbing height of surge waves.The results show that the surge waves obtained in this twodimensional water tank experiment mainly include three types:dissipative surge waves,weakly nonlinear oscillation waves,and nonlinear transition waves.The climbing process of different wave types is different,and the maximum climbing of surge waves is not necessarily generated by the first wave.Climbing angle β It is the main factor affecting the climbing height of surge waves.(2)Analyze the climbing heights of surge waves generated under different experimental conditions on flat plate slopes at different angles,and compare them with existing climbing prediction formulas to study the accuracy and applicability of existing climbing prediction formulas.The results show that the existing climbing formulas have high prediction accuracy for dissipative surge waves and nonlinear transition waves,with an error range of±25%.However,for weak nonlinear oscillation waves,the prediction accuracy is relatively low,and further research is needed to propose more accurate prediction formulas.(3)Taking the reservoir area of a certain hydropower station as an example,a threedimensional physical model experiment of potential landslide surge was conducted to study the types of surge waves generated by different volumes and shapes of landslide bodies in the reservoir area.The first wave height and attenuation law of surge waves were statistically analyzed,and the effects of factors such as landslide volume,reservoir water level,and sliding height on the first wave height of surge waves were analyzed,as well as the attenuation of the first wave height of surge waves along the way.The results show that compared with the twodimensional water tank experiment,the dimensionless range of the relative wave velocity of the first wave in all working conditions of the three-dimensional experiment is(0.0368 ≤c/cs ≤0.2386),and its first wave velocity is smaller than the solitary wave velocity.The range of the relative wave peak height of the surge wave is(0.0044≤ac/h ≤0.1368),and its relative wave peak height is smaller(ac/h<0.2),indicating a linear or weakly nonlinear wave,The main type of surge wave is weak nonlinear oscillation wave.The sliding height of the landslide,the depth of the reservoir area,and the volume of the landslide are the main factors affecting the height of the first wave of the surge wave.The first wave of a surge wave will experience attenuation along the way during its propagation upstream and downstream,and the greater the sliding height,the more obvious the attenuation along the way.(4)We studied the effects of factors such as the inflow velocity,sliding height,landslide volume,landslide shape,and reservoir water level on the maximum climb value of surge waves on the opposite bank,the climb value before the dam,and the overtopping water volume of the dam.The results indicate that the water level in the reservoir area and the inflow velocity of the landslide are the main factors affecting the rise of surge waves on the opposite bank and the amount of water overflowing in front of the dam.For landslide masses with different shapes,the upstream surface area is the main factor affecting the head height of surge waves. |
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