The Response Analysis Of The Vehicle-bridge Coupling Vibration In Old-bridge Widening Projects

In recent years, the number of new bridges has been dramatically increasingalong with the rapid development of China’s transport industry. Meanwhile, it hasalso been under way to reconstruct existent roads and bridges. Saving a lot ofinvestment, reconstructing old bridge can bring more economic benefits thanbuilding new ones can compete. In order not to affect the traffic, the passage ofvehicles is always admitted when the reconstruction is under way, and as a currentlyprevalent operation, an after pouring section is casted between the old bridge and thenewly constructed part to connect them. Actually, the vibrations and differentdeflections of the old bridge and it’s new counterpart will greatly affect the quality ofafter pouring section and the stress of the bridge structure. As a result, we have totake the traffic load into consideration when reconstructing old bridges.Based on a large amount of reference data, this paper studies the designs of theconstruction program applied to bridge-widening projects, and then summarizesmethods used in bridge-widening process by analyzing characteristics of thesemethods and conditions where they are applicable. To start with, how the spatial roadspectrum forms is studied here with the help of MATLAB programming system, andthen a sample of various grades of space road spectra is worked out,which isregarded as the excitation source of vehicle-bridge coupling vibrations. Meanwhile,with the aid of ABAQUS finite element software, vehicle-bridge couplingcalculation models of the simply supported T-beam, plate girder, box girder andother bridge types are respectively set up here, along with an in-depth analysis ofrespective responses of vehicle-bridge coupling vibrations in cases with differentvehicle speeds, levels of road, and ways of connection between the old and the newbridge. Finally, this paper, based on above studies, discusses methods to design andconstruct the connection of the old bridge and the new one, which can be used toreduce the impact of traffic loads on after pouring sections.