Study On The Influence Factors Of Vehicle-Bridge System Vibration And Ride Comfort Of Straddle Monorail Transit

Abstract:At present, few investigations of the vehicle-bridge system coupling vibration for straddle monorail transit have been addressed at home and abroad, which has effect on the further promotion and application of the technology. On the basis of the straddle monorail transit in Chongqing, the effect of vehicle and bridge factors on the coupling vibration and ride comfort of straddle monorail transit is studied. The main contents and research results are as follows:(1)On the basis of the model of vehicle, bridge, cornering and radial tire, vehicle unit, bridge unit, tire cornering and radial potential are deduced.(2)Track irregularity series on space are stimulated. According to the principle of potential energy with stationary value in elastic system dynamics and the "set-in-right-position" rule for forming structural matrices, the spatial coupling equations of straddle monorail vehicle-bridge system are established, and the procedure on train-bridge coupling vibration analysis is developed by Fortran90. The validity of the procedure is verified by comparing field-test data with calculating results, and the effect of wheel-rail contact state on the response of bridge shows that straddle monorail transit vehicle-bridge system vibration has obvious wheel-rail contact randomness, which verifies the validity of the procedure.(3)Based on the procedure above, the effect of wheel pressure, partial load of vehicle, and track irregularity on the coupling vibration is studied. The results are as follows:The effect of vehicle’s partial load is obvious. Longitudinal and lateral partial load has little effect on the displacement of bridge, and lateral partial load has great effect on the acceleration of bridge. Travelling wheel pressure has great effect on the vertical response of the train-bridge system, and steering and stabilizing wheel pressure have great effect on the lateral response of the system. The lateral acceleration of bridge changes significantly, and the effect on the acceleration of the system is greater than that on the displacement when all of travelling wheel pressure increases.(4)On the basis of Sperling index and acceleration value standard, the effect of wheel pressure, carrying capacity of vehicle, spatial load of vehicle, track irregularity, track beam span and stiffness on the ride comfort is analyzed. The results are as follows:On the analysis of the effect of the factors above on ride comfort, the evaluating results of with Sperling index are different from that with acceleration value standard. The change of lateral stiffness has great effect on the lateral ride comfort, while it has little effect on the vertical ride comfort. The change of verticle stiffness has great effect on the vertical ride comfort, while it has little effect on the lateral ride comfort. The stiffness of track beam has great effect on ride comfort, therefore, it is necessary to study the limit value of track beam stiffness.78figures,36tables,98references in total.