steel beams


Computer-Aided LRFD Analysis and Design of Bolted Splices for Steel Bridges

Firas I. Sheikh-Ibrahim, Ph.D., PE
Lead Engineer
Parsons Brinckerhoff Quade & Douglas, Inc.
Pittsburgh, PA

John C. Huang Ph.D., PE,
Principal
CHC Engineering, LLC
Herndon, VA

bridge spliceIn 1999, the American Association of State highway and Transportation Officials (AASHTO) adopted a new methodology for the design of bolted field splices of flexural steel members. The new methodology was developed in response to the lack of a uniform design methodology for bolted splices, which resulted in confusion and costly splices.

The new methodology includes new formulas for the web and flange forces as well as minimum design forces. It also includes new rules and formulas for girders with holes in the tension flange as well as the resistance of flange bolts when passing through fillers. To help engineers implement the new methodology, AISI's Transportation and Infrastructures Committee sponsored the development of AISIsplice software.

AISIsplice is a tool for the analysis and design of bolted field splices for straight, right, I-shaped, steel girders that follows the procedures of the AASHTO LRFD Bridge Design Specifications, Second Edition, 1998, including the 1999 interim. The 1999 revisions to the AASHTO Specification were based on research performed by Firas I. Sheikh-Ibrahim and Karl Frank (1996, 1998) at the University of Texas at Austin.

force diagramIn the design mode, the software sizes and optimizes the splice plates and bolts. In the analysis mode, the software determines the adequacy of given splice plates and bolts. For both modes, performance ratios (load/resistance) for all splice components are determined.

The software output consists of scaled graphics and a detailed report. Graphic illustrations include the elevation and cross section views of the splice and adjoined girders. Graphical output includes splice dimensions, bolt details, a summary of required filler plates, and splice component performance ratios.

When designing a splice, the Splice Design Summary screen appears. This screen contains graphical output of splice details, required filler plates and their locations, girder cross sections and elevation views, properties of the flange and web connection bolts, faying surface class, and performance ratios.

A useful feature of AISIsplice is the Adjust Design option. After a splice design is generated by the software, the user may modify the design to his/her preference. When this option is used all properties of the designed splice are loaded into the Splice Analysis module. The user may change selected properties of the splice, and then the program analyzes the splice.

In this lesson, you need to

  1. View the slide show: Computer-Aided Analysis and Design of Bolted Splice for Steel Bridges, which covers the theory behind AISIsplice software.
  2. Study the User's Manual of AISIsplice (V3.0) (2001 edition, 38 pages), which provides detailed guidance on how to analyse and design bolted splice for steel bridges using AISIsplice software.
  3. Download AISIsplice (V3.0) (30 day free trial version) and get familar with the software. You will be asked to solve some steel beam splice design problems when taking the quiz.
The AISIsplice User's Manual can be downloaded and be printed free of charge. Choose any of the formats below to start downloading:

Download AISIsplice User's Manual (a zipped html file, 1.60 MB)

Download AISIsplice User's Manual (a Word file, 1.04 MB)

Download AISIsplice User's Manual (a PDF file, 3.50 MB)

Once you finish viewing the slide show and studying the User's Manual of AISIsplice, you need to take a quiz to obtain the PDH credits.

Take a Quiz


***

Additional Technical Resource and Further Readings:

  1. American Association of State Highway and Transportation Officials, “LRFD Bridge Design Specifications,” 1999 Interim, Washington, DC, 1999.


  2. American Association of State Highway and Transportation Officials, “LRFD Bridge Design Specifications,” Second Edition, Washington, DC, 1998.


  3. American Institute of Steel Construction, “AISC Database Version 2.0,” Metric and English Units, Chicago, IL, 1994.


  4. American Institute of Steel Construction, “LRFD Manual of Steel Construction,” Volumes I and II, Chicago, IL, 1994.


  5. Sheikh-Ibrahim, Firas I., and Frank, Karl H., "The Ultimate Strength of Symmetric Beam Bolted Splices," AISC Engineering Journal, Third Quarter, 1998, pp.106-118.


  6. Sheikh-Ibrahim, Firas I., and Frank, Karl H., "The Ultimate Strength of Unsymmetric Beam Bolted Splices," AISC Engineering Journal, Second Quarter, 2001, in-print.


  7. Sheikh-Ibrahim, Firas I., and Frank, Karl H., "Bolted Field Splices for Steel Bridges," ASCE Proceedings of Structures Congress XIV, Volume 1, Chicago, IL, April 1996, pp.290-297.

***

Acknowledgment:

PDHonline.com acknowledges the sponsorship of American Iron and Steel Institute (AISI) for this online course.

***

Once you finish viewing the slide show and studying the User's Manual of AISIsplice, you need to take a quiz to obtain the PDH credits.


DISCLAIMER: The materials contained in the online course are not intended as a representation or warranty on the part of PDHonline.com or any other person/organization named herein. The materials are for general information only. They are not a substitute for competent professional advice. Application of this information to a specific project should be reviewed by a registered professional engineer. Anyone making use of the information set forth herein does so at their own risk and assumes any and all resulting liability arising therefrom.