Analytical method for overturning risk assessment of curved girder bridges with single-column piers under heavy-duty vehicles

Abstract

Overload-induced overturning of curved girder bridges with single-column piers occurs frequently, resulting in serious casualties and public property losses. Hence, it is essential to study the overturning mechanism of such bridges for an accurate overturning risk assessment. In this study, the dead loads of the bridge were first obtained considering the additional torque induced by the difference between internal and external self-weight, and the heavy vehicles-induced live loads were achieved accurately with the introduction of the trailer turning model. The mechanical model of the curved girder bridges with single-column piers was established, and analytical formulae of support reaction and torque considering bearing stiffness were derived based on the force method principle. Second, the assessment methods of the bearing disengagement state with combined support reaction force and torsion angle and overturning limit state with rotation of combined rigid body and deformation body were proposed, respectively. On this basis, the overturning risk assessment method of curved girder bridges with single-column piers was established for the two critical states. Finally, the entire overturning process of an example bridge was analyzed based on a finite solid element model, and the validity of the overturning risk assessment method was determined with the comparison of the evaluation results under critical loads.