The Research On Extent Of Turbulence Zone Around Pier And Width Of Navigable Bridge Opening

Setting out from the actual condition that there has portion bridge affect voyage for its navigable clear width is too narrow. Through analyzing the natural rivers and model test materials, we found that there are turbulence zone that affect navigation safety at both sides of pier. However, at present, the calculation formula about navigable bridge opening clear width doesn't consider the width of this district. So the research on extent of turbulence zone around pier and width of navigable bridge opening has very important theory and realism significance in the fields of choosing the clear span of the bridge rationally, preventing ship traffic happing from bumping into the pier, The thesis linked with Ministry of Communications trade unites the scientific and technological brainstorm project of "Investigation on channel renovation technology in bridge area", adopts general situation water though experiment and numerical simulations together to research turbulence zone width near the pier and the clear width of navigable bridge opening. After analyzing current structure around the pier, setting up a level two-dimensional turbulent mathematic model, used this model to calculate pier column circumfluence in straight channel and, the calculation result reflect the stream phenomena. In general situation water though experiment, Adopting advanced PIV test system and data processing procedure to carry on gathering picture and processing data, and we gained the picture of the surface velocity profile of the single mound and a pair of mounds at different intervals in straight and curve water though, then gained the width of turbulence zone of every experiment session. According to analysis and research of the width of turbulence zone around the pier and relevant respects etc, this thesis for the first time proposes that there should be a safe distance between the channel and pier for turbulence area exist around the pier, at the same time we should consider this distance in calculating the width of navigable bridge opening, later we put forward a new calculation formula to reckon the width of navigable bridge opening,. C4 was increased in the formula, meanwhile according as experiment data about how to reckon C4 value in straight channel and crooked channel was gave.