Experimental Study On The Analysis Method Of Bridge Traffic Impact Coefficient Test

With the constant development of the highway, the effect on the bridge has been afocus problem in the engineering field. Impact effect occurs when moving loads runover the bridge, and it is a structure dynamic augmentation effect. It is one of the mainindicators which is used for evaluating the safety of bridge and driving comfort, So ithas important significance on the impact coefficient research. At present, the impactcoefficient is defined as the maximum dynamic displacement and the maximum staticdisplacement ratio. There is no more accurate theoretical calculated method to get theimpact coefficient. However we can work it through the measurement of dynamicdeflection. In the practical engineering, dynamic deflection is mostly the relativemeasurement. It is limited by the bridge clearance, site conditions and equipmentinstallation condition. Sometimes the accurate measurement of dynamic deflection ofbridge is very difficult.Be based on statistical analysis on the most of sample data, the paper analyzes thereliability of dynamic impact effect which the moving loads reflect on the bridgestructure through the increasing coefficient obtained by the measured dynamic straininstead of impact coefficient. In order to overcome the limits of the bridge dynamicdeflection relative measurement, it uses the inertial sensors to measure the bridgevibration velocity and obtains the bridge structure vibration dynamic deflection curveby doing the filter, integral and recovery processing to the speed signal. Moreover, itdiscusses the feasibility of the absolute measurement method of the dynamic deflectionthrough the laboratory simulation test and field power test.Site measurement of the impact coefficient obtained many influence factors,mainly deck roughness, vehicle speed, Vehicle Bridge coupling vibration phasematching degree and dynamic load efficiency etc. For more objectively reflect thebridge structure dynamic impact effect caused by the moving loads, on the basis ofsumming up the effect factors of the impact coefficient, to the different span simplysupported beam bridge, it make quantitative analysis by using the numerical simulationsoftware to the Influence factors which was leaded by the difference, which of thevehicle-bridge coupling phase, speed and calculating method and so on, to the impactcoefficient test analysis results. At the same time, combination of domestic and foreign relevant norms, it discussed and analyzed the objectively of the impact coefficientamendment method; This paper, through the use of the site test results of three realbridge, analyzed the impact coefficients stochastic and dynamic load efficiencycorrelation, which make a foundation to evaluate the dynamic performance of bridgestructure more objectively and scientifically.