Evaluation of Short Span Steel Bridge Design Standards
The Federal Highway Administration’s National Bridge Inventory consists of over 600,000 bridges. Of these bridges, over 25% are considered either structurally deficient or functionally obsolete.
While several state bridge departments have standard designs for bridge components in order to speed up the design process in replacing these bridges, few have standard designs for the bridge superstructure.
Standard short-span steel bridge designs were developed to create a design aid for bridge engineers. In this package, designs with spans ranging from 40 feet to 140 feet in 5 foot increments were developed for rolled wide flange beams, homogeneous steel plate girder sections and hybrid steel plate girder sections.
The rolled sections were designed using two design approaches: the lightest weight possible and the lightest weight possible with a limited section depth. This limited suite provides the opportunity for stock piling common rolled beam sections and common steel plate sizes. In utilizing this design aid, a more efficient transition from design to construction can be achieved.
Contained in this report is a design evaluation of two sample bridges. Both of these bridges were 80-foot simple span bridges with cross-sections capable of carrying two traffic lanes.
One of the bridges evaluated utilized homogeneous plate girders for the steel superstructure whereas the other utilized rolled beams. Girders for these bridges were selected from the standard designs and evaluated according to current AASHTO LRFD Specifications.
Both design options are shown to perform adequately under AASHTO Specifications.
- Karl E. Barth, Ph.D.
- Amy S. Barth, Ph.D.
- Gregory K. Michaelson, Ph.D.
- Cory L. Gibbs, E.I.T.
- Robert M. Tennant
What is eSPAN140?
eSPAN140 is an innovative, interactive web-based preliminary design tool to assist bridge professionals in the optimal, most cost-effective design of short span steel bridges (those with spans up to 140 feet). It provides bridge professionals with a single resource to find optimized steel solutions for their projects—a “one-stop shop” for steel fabrication and erection details.
To begin to use eSPAN140, simply go to www.eSPAN140.com and create a free account. Then input information about your specific project, including span length, number of striped traffic lanes, skew angle and design speed, among other requirements. eSPAN140 then provides a customized “Steel Bridge Solutions Book” in PDF file format based on the specific input provided.
The Solutions Book includes:
– Standard designs for rolled beam, plate girder, buried bridge, and press brake tub girders.
– Contact information to design and build your bridge, as well as to provide pricing information.
-Access to complimentary design support.
eSPAN140 was updated in 2020 to include press-brake tub girder solutions and simplified buried bridge options.