Ground vibration propagation under road traffic with different vehicle types and shallow foundation thicknesses

Abstract Ground vibrations induced by road traffic are among the most significant challenges in urban environments and can affect both residents’ comfort and the performance of adjacent structures. Despite numerous studies in this field, the evaluation of the effects of vehicle type and the role of shallow foundations in vibration propagation, as well as the investigation of the phenomenon of resonance, still face limitations. In this study, a 2.5D numerical model based on the finite element method was developed to simulate dynamic vehicle–pavement–soil interaction, accounting for road surface roughness. The dynamic loads generated by the passage of different vehicles were calculated using a half-car model. Following model validation, a sensitivity analysis was conducted for vehicle type, shallow foundation thickness, and distance from the loading axis. The results showed that the truck was the most critical source of vibration, and the peak particle velocity (PPV) generated by it at a distance of 15 m from the road was 12.7 times greater than that of a passenger car. Furthermore, the occurrence of the resonance phenomenon within the range of 14 to 22 m from the road led to a renewed increase in vibration amplitudes. Increasing the foundation thickness from 0.5 to 4 m increased the reduction in PPV at 13 m from 7.25 to 42.28% and reduced the spectral energy of vibrations by up to 64.70%. In addition, the 4-m-thick foundation resulted in an 11 dB reduction in the vibration level at the dominant frequency. The findings of this study demonstrate the decisive role of vehicle type and foundation characteristics in controlling traffic-induced vibrations. They can provide a basis for the design and optimization of structures located adjacent to heavily trafficked roads.