Title:
Load Rating Criteria for Existing Concrete Bridges
Author(s):
John L. Carrato, Charles H. Hague, and Harold S. Sandberg
Publication:
Concrete International
Volume:
22
Issue:
2
Appears on pages(s):
45-52
Keywords:
bridge decks; live loads; load factors; loading rate; piles; service load method; structural design
DOI:
Date:
2/1/2000
Abstract:
A load rating is a simplified measure of the capacity of an existing bridge to carry live loads. The lowest rated bridge controls the rating of any stretch of road or railroad track, and the lowest rated member generally controls the rating of the bridge. This is theoretically correct and many engineers stop here. There are many factors that could and should be examined in order to arrive at the true rating, and engineering judgment must be applied to obtain a usable result. The methods used to calculate the load rating are only one part of the determination if a bridge is safe. This article discusses the issues that should be considered regardless of the method used to calculate load ratings. A case study using the Service Load Method of load rating is presented