Response of cracked simply supported concrete beam with moving vehicle load

Abstract

The dynamic response of a cracked beam subjected to moving loads has been studied extensively in the past decades. However, very little is known about the dynamic impact factors and crack propagation when vehicles move along the cracked beam. It can be reasonably postulated that a crack extension may occur when the vehicle loads cross the cracked bridge at a high speed. As a result, the dynamic response will be enlarged significantly due to the flexural rigidity reduction induced by cracks, which may result in a dangerous effect on structures. To address this problem, a three‐dimensional vehicle‐bridge model was developed to investigate the dynamic response of cracked bridges with crack breathing. Crack breathing is simulated at the crack surface using contact elements. The modified crack closure method is adopted to calculate the stress intensity factors. The results showed that the impact factors for the damaged bridge under a moving load could be notably larger than those for the intact bridge, and could exceed the value specified in the AASHTO bridge design code. Meanwhile, crack propagation may occur when the vehicles move along the cracked bridge at a high speed. So, it is very necessary to limit the velocity and transverse position of the vehicles to avoid further damage to the cracked bridge.

Experimental and computational study on dynamic analysis of cracked simply supported structures under moving mass

“…Omolofe et al [19] explored the influences of braking, acceleration, and constant velocity on the vibrations of prestresed structure under transit mass. Zhou and Liu [20] explained in their work the effects of and the impact factor and the propogation of crack on the vibrations of a damaged concrete structure subjected to a transit vehicle. Green function is one of the common methods used for determining the vibration behavior of damaged structures.…”

Erratum

“…The name of the second author was incorrect in the published version of this paper. The correct author name is Zhao Liu.…”