Investigation of the Fatigue Vehicle Load for a Long-span Steel Bridge Based on Nine Years of Measured Traffic Data

Abstract

ABSTRACT This study conducts a rational investigation of nine years of traffic monitoring information concerning the Jiangyin Yangtze River Bridge within which the traffic flow, vehicle composition, vehicle load and axle-weight features are analyzed and discussed. Based on the annual analysis of traffic information, it is observed that compact cars weighing less than 30 kN account for 61% of the total traffic volume. According to the number of axles, wheelbase and axle groups, the vehicles in the traffic flow are classified into 11 representative types. Among them, two-axle vehicles form the major category, accounting for 80% of the total traffic flow. Statistical analysis of the gross vehicle weight and axle weight indicates that the gross vehicle weight follows a bimodal normal distribution, whereas the axle weight follows diverse distributions, including a normal distribution and an extreme distribution. In addition, by using equivalent damage theory, five equivalent vehicle models are established according to measurements of the axle weight and wheelbase. Finally, a six-axle fatigue-loaded vehicle model is proposed and discussed.