Structures Design Guidelines | Jan 2007
5 - Superstructure - Steel |

# Chapter 5 - Superstructure - Steel

## 5.1 General (07/06) July 2006 Revised per TDB C06-04.Per TDB C05-15, revised 5.1 A.,B., and C. Per TDB C04-04, added 5.1.1 Corrosion Prevention. Added 5.1.D (Constructability Reference)

A. Design straight steel bridge components in accordance with LRFD 3rd Edition (2004), with 2005 Interim Revisions excluding Section 6, 2006 Interim Revisions excluding Section 6, and the requirements of this chapter. (See Commentary in SDG I.6)

B. For a bridge with curved steel members for part or all of its length, design the entire bridge, including substructure (with the exception of the traffic railings) in accordance with the 2003 AASHTO Guide Specifications for Horizontally Curved Steel Girder Highway Bridges and the AASHTO Standard Specifications for Highway Bridges, 17th Edition, with a HS-25 live load.

C. Design the traffic railings and all other bridges within the same project in accordance with the AASHTO LRFD Bridge Design Specifications. On all bridges, use the current Structures Design Guidelines as appropriate.

D. Refer to AASHTO/NSBA Steel Collaboration Document G12.1 Guidelines for Design for Constructability. http://www.steelbridge.org/

### 5.1.1 Corrosion Prevention

A. To reduce corrosion potential, consider special details that minimize the retention of water and debris.

B. Consider special coatings developed to provide extra protection in harsh environments.

C. Consider the corrosion potential of box structures versus plate girders. Box Girders are preferred compared to plate girders when located in extremely aggressive environments.

D. See the Plans Preparation Manual 2.10.1 for minimum vertical clearances.

### 5.1.2 Girder Transportation

Coordinate the transportation of heavy and/or long girders with the Department’s Permit Office during the design phase of the project.

### 5.1.3 Dapped Girder Ends (07/06) July 2006, Added section prohibiting dapped girder ends.

Dapped steel box girders or dapped steel plate girders are not permitted.