| Vehicle-bridge coupling vibration performance is an important research of bridge structure dynamics,corrugated steel web box girder is highly praised for its good overall mechanical performance and good material utilization efficiency.However,the research on the vehicle-bridge coupling of corrugated steel web box girder is less than that of concrete girder.On the other hand,the requirement of vehicle-bridge coupling performance calculation for complex bridges makes a familiar simulation method acceptable to most engineers particularly important.Therefore,with the support of Key Project of Chinese National Programs for Fundamental Research and Development(2016YFC0701202),Academician Special Project of Chongqing Foundation and Frontier Research Program(cstc2015jcyjys0011),the vehicle-bridge coupling vibration of corrugated steel web box girder is studied.The main research contents and conclusions are as follows:(1)By referring to the previous method of simulating road surface roughness with constraint equation,the improved displacement contact method is used to form the contact constraint method,that is,the point-surface contact between the vehicle model and the bridge model is established to form the vehicle-bridge coupling system,and the vehicle-bridge coupling simulation solution considering road surface roughness is realized with time-varying constraint equation.This paper describes the implementation of this method in ANSYS in detail and verifies the accuracy of this method.(2)Taking the corrugated steel web simply supported box girder with a span of 30 m as the object,36 kinds of working conditions with different driving speeds,different road surface grades and different road surface forms were calculated,and the displacement response data and acceleration response data of measuring point were extracted respectively.The high-frequency vibration amplitude in the displacement response is obtained by high frequency filtering of the displacement response data,and the impact coefficient is obtained by dividing the maximum amplitude by the maximum static displacement.(3)When studying the impact law of influencing factors on impact coefficient,it is found that: the influence of vehicle speed on impact coefficient is often interfered by other factors,for example,the influence law may be different in different pavement grades;the influence of pavement grade on the impact coefficient is linear,but the improvement of impact coefficient is related to the position of box girder and pavement form;the impact of pavement form on the impact coefficient is also determined,that is,considering the three-dimensional pavement is lower than considering the two-dimensional pavement,but the lower amplitude is affected by the pavement grade.When the corrugated steel webs in the original box girder are replaced by straight steel webs,the impact coefficient is close,and the difference between them is only within 0.005.When the concrete floor of the original box girder bridge is replaced by steel floor,the impact coefficient increases by nearly twice on average.(4)When studying the influence law of influencing factors on peak acceleration,it is found that: the peak acceleration response of box girder increases with the increase of vehicle speed and is not affected by pavement grade and pavement form;the peak acceleration response of box girder increases with the improvement of pavement grade,but the improvement amplitude of two-dimensional pavement is larger than that of threedimensional pavement;the average value of the peak acceleration response of the same level of road surface under the same pavement form is calculated.When considering the three-dimensional road surface,it is lower than that when considering the twodimensional road surface,but there are some individual working conditions contrary to this rule. |
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