Fatigue Load Model Using the Weigh-in-Motion System for Highway Bridges in China

The development of the Chinese economy is associated with many changes in vehicle loads, particularly the increasing numbers of heavy trucks and other types of vehicles. However, currently, no standard vehicle has been identified for studying the fatigue design of highway bridges in China. Using the weigh-in-motion system, the authors obtained vehicle loads of 23 Chinese provinces. Miner’s rule for cumulative fatigue damage was then used to categorize each vehicle as one of eight representative types according to load. From these types, five equivalent vehicle models were found. Subsequently, simplified fatigue load spectra for highway bridges were obtained for each province. The six-axle vehicle can be used as the standard fatigue vehicle for most provinces, except in Zhejiang and Guizhou, in which three- and four-axle vehicles are most representative. Also, a standard fatigue vehicle for China is proposed.