Parameter Studies of Moving Force Identification in Laboratory

Abstract

The parameters of both vehicle and bridge play an important role in moving force identification. This chapter aims to investigate the effect of various parameters on Time Domain Method (TDM) and Frequency-Time Domain Method (FTDM). The model car and model bridge deck were constructed in the laboratory. The Axle-Spacing-to-Span-Ratio (ASSR) was set to be 0.15 and the model car had two axles at a spacing of 0.55 m and it ran on four rubber wheels. The static mass of the whole vehicle was 12.1 kg in which the mass of the rear wheel was 3.825 kg. The parameters, such as the mode number, the sampling frequency, the speed of the vehicle, the computational time, the sensor, and sensor locations were considered as variables to examine their effect on the accuracy of force identification. The TDM is found to have higher identification accuracy when the higher sampling frequency is employed. However, the FTDM is failed if adopting higher sampling frequency and lower mode number. Both the TDM and FTDM can effectively identify moving forces in time domain and frequency domain respectively, and can be accepted as a practical application method with higher identification accuracy.