Incorporation of Skew Effects in Live-Load Distribution Factors Developed for Typical Integral Bridges

Abstract

In current bridge design specifications, no provisions exist for live-load distribution (LLD) in the components of skewed integral bridges (SIBs). Thus, in this study, skew correction factors (SCFs) were developed for the girders, abutments, and piles of SIBs to adjust the readily available LLD formulae for integral bridges (IBs). For this purpose, two-dimensional (2D) and three-dimensional (3D) structural models (SMs) of numerous SIBs were constructed and then analyzed to calculate the LLD factors (LLDFs) for SIB components as a function of the skew angle and various structural parameters. The ratio of the LLDFs for SIBs to those for the same bridges with no skew were then used to formulate SCFs. Live-load (LL) effects in SIB components were then simply obtained by multiplying the SCFs with the results obtained from the readily available LLD formulae in the literature. The comparison of the results with those from structural analyses revealed that using the developed SCFs together with readily available LLD formulae for regular IBs yields reasonably good estimates of LL moment and shear in SIB components.