Study On Routing Model And Impact Loading Of Flood

China is a calamitous country.The kinds,the intension and the frequency of the disaster are all on the top of the world.In all of the disaster,the biggest losing is made by flood.After 1949,the losing made by the flood reached to 40%in the total losing made by all kinds of disaster.For many years,people have always considered that the effective time of the impact of the flood was short and the range of the impact was limited.So no one regards the impact of the flood as a primary acting force on the building.The flowing direction of the the flood and the action range of the flood can't be forecasted.As a result,after the flood a lot of buildings were washed off.Recently people call for a higher security standard of the building with the development of the economy.So founding the impact loading model,researching the infection of the impact to the building and improving the ability of resisting the impact of the flood of the building is a important research work.Based on the one-dimensional Saint-Venant water equations explicit difference scheme,a new explicit difference scheme is deduced to establish the evolutionary routing model of flood by taking account into the bottom slope item and resistance to water-flow item.The water depth,current velocity and other parameters of flood at different time and distance during propagation process could be calculated with this model.By using this model, the water depth and current velocity are calculated in three kinds of condition.The computational formula about the impact loading of flood model is deduced by, based on the sets of water depth,current velocity and impact time data,combining the one-dimensional unsteady flow energy equation and the analytic solution of flood routing in this paper.The impact loading of flood at different time and distance could be calculated simply with this formula.According to the formula,the value of the load relates to the upstream static level,distance,the height of the impact face and the impact time etc.When all of the parameters are determined,the load will change linearly with the depth of water.Finally, twenty-one kinds of numerical analysis are carried out by calculating the impact loading and the variation rule of the impact loading is discussed.At the same time,three groups of model experiment are made and the experiment results are compared with the theoretical results.