Determination of the optimum dimensions for the bridge piers under the effect of sediment transport and dynamic loads

Bridge is one of the essential parts of the transportation network. Static and reinforced concrete calculations in the design of bridges are often insufficient. The most important reason of this is the difficulty of examining the hydraulic effect on the bridges. Hydrological survey of the river-basin, river?s natural sediment transport capacity, the existing regulation buildings and morphological structure should be examined during the design phase of the bridge. The most appropriate stream section, pier form and location for the bridge should be determined in accordance with these data.Under the scope of this thesis, local hollows on the piers of the bridge caused by the stream and the effect of the bridge pier geometry have been studied. The level of the hollow occurred around the bridge piers has been tried to be calculated, based on the academical studies done until today. The thesis consists of six chapters.In the second chapter, the effect of the bridge piers located on an unstable base on the stream area have been observed, and also the new systems that occur around the piers due to the change at the stream have been examined .In the third chapter, the solid sediment movements in a river with an unstable base and the influence of the bridge piers on solid sediment movement have been examined. A comparison of the experimental studies made until today has been made.In the fourth chapter, the parameters that affect the hollows around the bridge piers have been tried to be explained. The fifth chapter includes experimental studies about the hollows around the bridge piers made until today and empirical connections obtained as a result of these studies.And in the sixth chapter, the bridge over the Lalaiver in Edirne river-basin, the apron of which collapsed during the wild rain on 8 September 2009 has been examined. At the end of this analysis, a suggestion for the most appropriate river section and pier type for the bridge has been developed.Key words: Bridge piers, local hollows