Horizontally Curved Steel Bridge Girders 2

[WideMike]

Shortly I'm going to begin preliminary design of a horizontally curved (2-span) steel girder bridge using LRFD methodology. Other than AASHTO-LRFD manual, which I have, anyone know of other references? Solved example problems would also be great. Thanks.

 

[CanyonRat]

You need to do a lot of reading. There is no LRFD Spec for curved steel girders yet. The AASHTO Guide Spec is currently only LFD and ASD.

The best reference I can recommend is the AISC Bridge Handbooks that can be found at

http://www.aisc.org.

Look for the Highway Structures Design Handbooks Second Edition.

I suggest you find some good software to do it for you if the curvature is great enough to require the in-depth analysis. If the curvature will allow the partial stress analysis then you can spreadsheet it fairly easily.

Currently the NSBA will rent their V-Load Program or you can use MDX

http://www.mdx.com

but it's about 6k. If you are good enough with finite element analysis the new edition of STAAD Pro will do true curvilinear elements. You would have to model the girders with elements instead of just the section props.

Good Luck,
MikeD

 

[peinnj]

I wrote most of the fortran code for performing the analysis portion of steel curved girders modelled using Finite Elements in STAAD. The analysis is based AASHTO LFD modified by the Penn DOT Design Manual. We were still testing the software at the time I left the company. But it seemed to work. There are programs for the inputting the structure into STAAD and processing the results. You'll need a fast computer. A composiste simple span structure of 60 or so feet in length with 5 to 6 girder lines and multiple changes in cross-sectional area of the stringer with diaphragms also modelled took 30 hour to run in STAAD on a 1.7 Ghz Pentium 4 Computer. Output File sizes ballooned to 100 MB. The fortran pre and post processing software programs were quicker to run and were using to process these large files.

Talk to Dr. Leon Lai, P.E., Specialty Engineering, Inc. (215) 428-2995. For details.

Martin Dragan, PE

 

[se123]

I am doing my research work in the area of horizontally curved I-girder bridges with emphasis on flange local buckling.

Design examples for curved I and box girder bridges has been recently published by AASHTO. This is the work of Dann H Hall, Michael A Grubb (Bridge Software Development International Ltd. PA) and Chai H Yoo (Professor, Auburn Univ). The example are detailed along with commentary.