Memorandum |
TO: | All Design Section Staff |
FROM: | J. Kapur |
DATE: | September 25, 2002 |
SUBJECT: | Segment Limits For Steel Girders |
This memo addresses shipping and handling limits for steel bridge girders.
Design segment weights, lengths, widths, and depths to meet shipping requirements. This can be achieved by placing field splices at appropriate locations.
For shipping purposes, segment weights shall be limited to 200 kips, 180 kips being a desirable maximum.
Curved girders should fit within a rectangle 14 feet wide in plan dimension. Wider girders will require special permits and accommodations. Segments 8 feet deep and 140 feet long have been successfully shipped by truck. Underpasses at sag vertical curves can limit deep and long segments. Haulers and the Bridge Preservation Office should be consulted for longer, deeper segments and remote locations. Bridge restrictions may also be in effect on some routes.
Maximize segment lengths while staying within these shipping limitations. Excessive use of splices will not result in the best solution.
Background
On a recent steel bridge project, special permits and hauling equipment were required to move heavy girder segments. This could have been avoided, and the shipping done more economically, by using shorter girder segments. Shorter segments may also be required where space is limited for delivery or placement.
If you have questions, please call Nate Brown at (360) 705-7219.
JK:dsb
NSB