Research On The Effects Of Vibration And Fatigue Characteristics Of Reinforced Concrete Simply Supported Girder Bridges

With the construction of western mountains area of China and the development oftransportation, a large number of heavy vehicles must go through the highway while theweights of these vehicles are far exceed the standards. Furthermore, due to overloadoperation of the existing reinforced concrete girder bridge and miss-realizing of thevibration effects on the life of the bridge by vehicles in its design, the reports ofaccident to the bridge due to fatigue damage are always around us in recent years.Therefore, it is need to pay more attention to the problem that whether the bridges onthe route can meet the needs of transport development, how much impact on the fatigueperformance of the existing bridge because of global and local vibration of the bridgewhile the heavy vehicles are going through the bridge.This paper aimed to analyze the vibration feature and the fatigue performance ofthe reinforced concrete simply supported girder bridge on the loads of heavy vehicles,provide the proof of the theory that structural vibration increase fatigue damage, andreveal the internal laws of vibration and fatigue. In reference to the research of thebridge fatigue of domestic and foreign scholars in recent years, this paper used theaccumulative fatigue damage theory to analyze the fatigue of reinforced concrete simplysupported girder bridge. Specific content:①The dangerous section on the longitudinal direction of bridge and the dangerouspoints which have the relatively large stress the load of vehicles by the luffing stressmethod were found.②The equivalent fatigue car models by the actual traffic volume by statisticalmeans which stand for the western mountains area was established; The feature oflateral distribution of vehicles was found which fit the actual situation by the analysis oflateral position of the vehicle with probability methods and the vertical deflection ofbridge.③The vertical distribution of the dynamic response and fatigue performance wassummarized by the analysis of reinforced concrete bridge on the longitudinal dynamicloading on the fatigue car model; The limitations and referential ability of finite elementvibration analysis were analyzed. ④The analysis of stress response from finite element model on the dynamic loadof the fatigue car model with ANSYS was achieved; The intrinsic relationship betweenthe fatigue performance of structure and the structural vibration was explored.⑤According to the dynamic stress response spectrum of the reinforced concretebridge under the dynamic load of the fatigue car model, the fatigue performance of thekey points of reinforced concrete simply supported girder bridge were calculated andevaluated.