Autostress Design (ASD) is a new method for designing continuous steel bridges. It was developed at the U.S. Steel Research Laboratory, under the sponsorship of the American Iron and Steel Institute and it is an extension of Load Factor Design (LFD).
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Autostress Design (ASD) is a new method for designing continuous steel bridges. It was developed at the U.S. Steel Research Laboratory, under the sponsorship of the American Iron and Steel Institute and it is an extension of Load Factor Design (LFD).
Considerable research has been devoted to the development of Autostress Design. This research included linear elastic and nonlinear analysis, tests on full scale components, and tests on a 1/2 scale model bridge. However, since the method represents a departure from existing practise. it was believed that testing of a full scale bridge was needed to verify the method before it would be widely accepted by the practicing profession. The Whitechuck River Bridge in Mt. Baker National Forest near Darrington, Washington was selected as this test bridge. It was designed by the Autostress Method and extensively instrumented during the fabrication and construction process.
This is the summary of the final report on the load test and analysis of its results.