Research On Narrow Lane For Vessels Of Bridges Constructed With Parrallel Ways At Bridge Group Reach

Along with the rapid development of national economy, the government strongly support the traffic construction, a lot of large water bridges were built in succession, that makes regional economic prosperity and stability. Because of various factors in bridge site selection and design,such as the shoreline resources, requisition, etc. Then which lead to construction of many Bridges in relatively short range of channel.Though the Parallel bridges building can greatly save the bridge resources, but for navigation of the ships within the bridges, and bridge is built, the installation of the bridges form the so-called "tunnel effect". When the ship drives through the bridges, it will hit the bridge if not careful operation, that can threat to safety of ships and bridges seriously.Therefore, to carry out the analysis of tunnel effect in bridge group rivers is imminent.Based on Chongqing Caiyuanba bridge group river, it uses the bridge group of hydraulic integral model and small scale remote control model of the ship to carry out the research in this paper. According to the order of river bridges construction, A wide range, multiple sets of time series of experiment was carried out. Combined with the mathematical model for the further study of effect of roadway, the paper puts forward suitable for and construct a navigable clear width formula:When composed of two bridges,When composed of three bridges,Through the results of physical model and mathematical model analysis, the paper get the factors of tunnel effect. They are bridge span,oblique flow and the length of the roadway.The bridge navigable clearance formula and its influence factors in the paper,can not only provide a scientific basis for the design of the bridge groups and technical support, but also provide technical support for the revision of the inland river navigation standard.