Effects of road surface roughness on the dynamic impact factor of bridge are investigated through full-scale field loading tests under controlled traffic conditions. The dynamic time histories of displacements are obtained for twenty-five bridges on Korean highways. The impact factors of the bridges are evaluated by using the measured displacements. The road surface profiles of the twenty-five bridges are also measured at every 10 to 30 cm interval in the span direction. By using the measured road surface profiles, the international roughness index (IRI) and the roughness coefficients of the bridges are evaluated. The linear regression and correlation analyses are performed to obtain the coherences between the IRI and the roughness coefficient and between the IRI and the impact factor. The sample correlation coefficients between the impact factor and the IRI and between the impact factor and the roughness coefficient are calculated to be 0.61 and 0.62, respectively, showing a strong coherence between the road surface roughness and the impact factor.Key words: bridge, impact factor, road surface roughness, international roughness index, roughness coefficient.
This paper describes the results of a project which employed impulse radar to detect faults existing beneath the surface of an asphalt-covered bridge deck at Papineau Creek, Ontario. A simple but enlightening mathematical analysis is provided which accurately predicts the waveforms actually observed. The methodology clearly demonstrates the usefulness of impulse radar as a diagnostic tool in remote sensing. Amongst the problems discussed and solved are: the identification of faults due to debonding, scaling, and delamination; the measurement of asphalt thickness at selected locations on the bridge deck and hence the determination of average thickness over the entire bridge deck; and the automated processing of the data using a computer. A comparison of the radar detected faults with those detected using conventional methods is provided. A set of parameters has been developed which permits data to be reduced to a simple set of measurements that can be plotted for visual inspection.
Dans cet article, on decrit les r6sultats d'un projet dans lequel on a utilise un radar impulsionnel pour detecter les defauts sur la surface d'un pont asphalte a PapineauCreek, Ontario. On utilise une methode d'analyse simple qui calcule avec precision les formes d'onde observees. La methodologie demontre clairement l'application du radar impulsionnel comme un outil pratique dans les applications de detection des objets eloignes. On etudie les problemes suivants: l'identification des defauts dus aux "debonding, scaling" et a la "delamination." On fait une etude com parative pour la detection des defauts observes par la methode proposee et par d'autres methodes usuelles. On etablit un ensemble des parametres qui permet la reduction des donnees en un ensemble de mesures pour inspection visuelle.
|
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.