New Safety-Based Checking Procedure for Overloads on Highway Bridges

Abstract

Overweight trucks exceeding legal weight limits are seen crossing highway bridges. Many states adopt the AASHTO rating concept with or without an overstress criterion to check overweight permits for bridge evaluation. However, the basis of these overstress criteria has not been well documented, and the AASHTO load-rating concept is not intended to be applicable to overweight truck traffic. The development of a new overload-permit checking procedure for bridge evaluation, in the format of load and resistance factors and based on relatively uniform bridge safety, is presented. Annual and trip overload permits for nondivisible loads are covered. This procedure may be included in bridge evaluation codes for overload checking.

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