| Three methods are presented which can be used to provide an inventory and operating ratings for composite/noncomposite steel structures with a concrete deck. Two of the methods, the Working Stress Rating (WSR) and the Load Factor Rating (LFR) methods are codified within the AASHTO specifications. The Autostress Rating (ASR) method is proposed, fully developed and implemented, along with the WSR and LFR methods, in a computer program. All three methods are used to rate a series of 16 representative bridges where the results are compared and trends obtained. The correlations lead to predictions on how much each method can yield in a level of reserve strength in order to accommodate the overload vehicles which regularly traverse the bridges nationwide. |
