Document Type



Available under a Creative Commons Attribution Non-Commercial Share Alike 4.0 International Licence


Civil engineering, Municipal and structural engineering

Publication Details

Journal of Bridge Engineering, ASCE - Volume 20, Issue 10 (October 2015).

Available here.


HL-93, the current bridge traffic load model used in the United States, is examined here. Weigh-in-motion from 17 sites in 16 states, and containing 74 million truck records, is used to assess the level of consistency in the characteristic load effects implied by the HL-93 model. The load effects of bending moment and shear force are considered on single-lane and two-lane same-direction slab and girder bridges with a range of spans. It is found that the ratio of WIM-implied to HL-93 load effect varies considerably from one load effect to another. An alternative model is proposed which achieves improvements in consistency in this ratio for the load effects examined, especially for the single-lane case. The proposed model consists of a uniformly distributed load, whose intensity varies with bridge length.