Deflection and Bending Moment Dynamic Load Allowance of Taxiway Bridges: Theoretical and Numerical Studies

The deflection response represents the overall deformation of a bridge, whereas the bending moment response highlights localized stress concentrations. Bridge design and safety assessments involve a combination of these two responses. However, research on the deflection and bending moment dynamic load allowance (DLA) of taxiway bridges remains insufficient. In this study, the mathematical expressions for the bridge deflection and bending moment DLAs were derived. Subsequently, a dynamic analysis program for aircraft–taxiway bridges was developed and validated using strain data from the field monitoring of the taxiway bridge at Qingdao Airport. Next, the deflection and bending moment DLAs of 20 taxiway bridges with different spans and widths were analyzed using finite element models. This study specifically explored the influence of the girder position, cross-sectional location, deck roughness, and taxiing speed on the DLA. The results indicated that the deflection DLA consistently exceeded the bending moment DLA. The maximum DLA of taxiway bridges occurred near the edge girders where reverse bending exists. Additionally, the ratio of the deflection to the bending moment DLA (RDM) stabilized at approximately 1.5 for positions away from the center girder. The highest RDM occurred at 1/2, 1/3, 1/4, or 1/8 of the span. The RDM of the center girder initially increased with the roughness, but eventually decreased, whereas the roughness had no significant effect on the RDM near the edge girders. The RDM was also minimally affected at taxiing speeds of 45–60[Formula: see text]km/h.