Abstract:The vibration response of bridge under vehicle loads is characterized by complexity and uncertainty. The impact coefficient, as an important indicator for measuring the dynamic effect of bridges, is influenced by multiple factors, such as vehicle type, vehicle speed and longitudinal position along the bridge. To reveal the influence laws of various factors on the impact coefficient, based on the ANSYS finite element analysis platform, a vehicle-bridge coupled dynamic calculation model is established to simulate the bridge crossing situations of different types of vehicles under various working conditions, and a series of numerical simulation studies are carried out. Taking the Ningzhenjie - Qixianghe section of National Highway 312 as an example, the vertical displacement dynamic amplification coefficients at the different lengthwise positions of the bridge are extracted to analyze the coupling relationship between the vehicle speed, vehicle type and the response position. The results indicate that under the high-speed conditions, the impact effect of bridges is significantly enhanced, and the dynamic response at the mid-span position is the most sensitive. The impact coefficient generated by two-axle vehicles is larger than the specified value. The research results can provide a theoretical basis for the reasonable correction of impact coefficients and the dynamic safety assessment of bridges.
