Evaluation of Girder Distribution Factor in PSC Girder Bridge with Curved Concrete Slab Based on AASHTO Specifications

The focus of this paper was on the development of a new girder distribution factor (GDF) for curved slab on straight girder bridges. To predict the behavior of prestressed concrete (PSC) girder bridges, finite element analyses considering a modeling strategy were conducted. A comparison was drawn between the finite element analyses and the results of a field test, to show the feasibility and application of finite element analyses. A total of 73 models were made, with different variables. A comparison was made between the GDFs in the current American Association of State Highway Transportation Officials (AASHTO) standard specification (2002), in the AASHTO LRFD standard specification (2007), and in the results of finite element analyses. Based on these analyses, GDFs in the AASHTO specifications were overestimated in most bridges, but underestimated in some bridges, especially bridges with curved slab. In this paper, a new GDF equation was proposed, using nonlinear regression analysis in the PSC girder bridge with curved slab, to rationally evaluate wheel load distribution. The proposed GDF equations are expected to provide a refined live load analysis for the PSC girder bridge with curved slab.