Overturning behavior analysis of curved single column pier bridge under combined action of heavy load and moderate-strong earthquake

Here, to explore effects of combined action of mobile vehicles and moderate-strong earthquakes on anti-overturning of curved beam bridge, a vehicle-bridge-earthquake analysis model was established, and a vehicle-bridge coupled vibration analysis method considering seismic effects was proposed for curved beam bridge. Taking a multi-span curved continuous beam bridge as the study object, contrastive analysis was performed for support reaction and overall turning angle of main beam when it overturning under combined action of moderate-strong earthquake and overloaded vehicles in biased loading state. Effects of seismic motion types, peak values and key vehicle parameters on the overturning stability of curved beam bridge were studied. The results showed that different combinations of vehicle loads and seismic loads can change bridge stress situation, when three 100 t vehicles with a longitudinal spacing of 2 m are driving at a speed of 3 m/s, overturning of a 3-span curved beam bridge is most obvious; comprehensively considering combined action of heavy load and earthquake, the stability coefficient calculation formula in anti-overturning specification is revised; effects of eccentricity of middle pier support of a 5-span curved beam bridge on its anti-overturning stability coefficient are analyzed, the maximum anti-overturning stability coefficient of the bridge is 1.55 when 2 adjacent supports of its middle pier are set with eccentricity. © 2024 Chinese Vibration Engineering Society. All rights reserved.