Dynamic analysis of orthotropic bridge deck under moving vehicular loads by using Hencky bar-net model

Abstract

This study extends the Hencky Bar-Net model (HBM) to dynamic analysis of vehicle-orthotropic bridge deck interaction system. The HBM was used to investigate the dynamic behaviour of an orthotropic bridge deck under moving vehicular loads and random road irregularities. The results indicate that the lower bending rigidity in width direction change the deformations of orthotropic deck from a global mode into a localized one, and dynamic magnification factors do not necessarily increase with higher vehicle speeds. However, dynamic magnification factors demonstrate an obvious increase in relation to higher vehicle speeds when the bending rigidity ratio is high. In addition, the HBM can easily handle damage of the bridge deck because of its discrete characteristic. Hence, the common longitudinal cracks that keep open are modelled by reducing the spring stiffness in the HBM. The results demonstrate longitudinal cracks show a complex influence on dynamic magnification factors of the bridge deck depending on the crack depth and location.