Study On The Reasonable And Selection Method Of Bridge Spacing

Along with the national sustainable development strategy of further rapid development of national economy, built a large number of inland waterway bridge across a river. This makes the speed of the construction of the bridge appeared an unprecedented growth. But the construction of the bridge and river is closely related to the channel condition accordingly. Because of the different level of channel spacing requirements between the bridge is not the same. If we don’t strictly in accordance with the requirement of the relevant to construction, once the major water traffic accident happened on the waters, for example, boat bridge accidents. Could cause blockage of the bridge approach shipping will be forced to interrupt, this will cause serious economic losses and social impact. So in order to reduce accidents, and timely to carry out the influence the channel condition of bridge distance discriminant standard and ship collision probability simulation research is necessary.In this paper, based on the Yangtze river in chongqing city proper period to affect the channel condition of bridge distance discriminant standard and ship collision probability simulation research. This research adopts the bridge group of2-d flow mathematical model and mathematical model of ship, a bridge of the ship sailing and the influence of the bridge under different channel condition reasonable spacing series study. The navigation condition of river is studied in detail on the different combination of bridge span and bridge and the influence of ship collision probability of bridge. Study on channel condition under the condition of different distance between bridge how to identify and determine the probability of ship collision bridge; And Bridges distance and span of the coupling relationship between show that is close to the group of river bridge span and the bridge span. When the interval distance is less than the required minimum distance of a bridge, spacing decreases at the same time should be multiplied bridge span, are also put forward the corresponding solution. Research is the unity of the different type river bridge span calculation formula:D＝ξ(nVa+△D),ξ stand for ship type for water flow, ship dimensions, such as bridge span and romantic space comprehensive influence coefficient of the bridge, n take5min, Va for launching ship speed on the other side,,△D (Dr or Df) braided river channel to the influence of bridge span, the added value. This formula, physical meaning is clear, complete parameter expression, calculation is simple.Based on the mathematical model and ship model experiment method, the research results can be defined group of "bridge" in the future, the location of the bridge, and across the bridge navigable will provide a scientific basis for related research, also provide reference for the scientific decision of the competent department.