Study On Driving Comfort Of Cable-Stayed Bridges With Moving Vehicles

For modern bridge structures, owing to its increasing spanning capacity andsoftening stiffness, as well as the high risk of effects coming from vehicle loads,driving comfort on bridges has aroused people’s attention gradually. Especially,driving on the cable-stayed bridges, the obvious vibration can lead to the sense ofinsecurity for passengers, resulted from the great flexibility of this kind of long-span structures. Consequently, driving comfort on cable-stayed bridges hasbecome the issue. Based on the calculation of coupled vibration system of vehicleand bridge, research of driving comfort on the cable-stayed bridges is conductedin this dissert, referring to the ISO specification and Sperling indicators. And theentire researches are listed as follows:Using the theory of structural dynamics vehicle and bridge dynamicequilibrium equation is deduced, based on the modal synthetic method on twoequations are coupled vehicle-bridge coupling dynamic equilibrium equation isobtained, the calculation method of solving time-varying system of differentialequations is introduced, and the deck is not flatness of simulation method.Based on theoretical derivation, using MATLAB language to compile thedriving comfort VBCVA dedicated computer program, program way of thinkingfor Wilson-θ method is used to calculate the process of vehicle-bridge coupledvibration, when get the vehicle dynamic response process and converted intofrequency spectrum, and then through the evaluation method to calculate thedriving comfort. Check and correct program by an example.Summarizes the current international popular driving comfort evaluationmethod and the sifting the two suitable for this article introduced in detail, theequations of the numerical discrete random vibration spectrum analysis of the data.Choose Harbin matsuura bridge for calculating bridge example, finite elementanalysis software ANSYS for dynamic characteristics calculation was carried out,and will in the first10order frequency is compared with measured values, theerror is within10%. Introduces the model of the three types of vehicles (trucks,bus and small cars) of dynamic parameters, and each of the vehicle drivingcomfort weighted calculation method. Using VBCVA program analysis of ISO international standards and Sperling evaluation two kinds of evaluation methodsunder different vehicle type, speed, bridge deck is not flatness, spacing and laterallane number and the relationship between the driving comfort. Found theimportance of the various influence factors under different evaluation methods aredifferent, but no matter choose what kind of evaluation method, the deck is notflatness are the main factors that affect the comfort of driving.