DP-102 Bridge Construction (Narrow Gap Improved Electroslag Welding)
Narrowing the ESW Gap

On February 16, 1977, the Federal Highway Administration issued FHWA Notice 5040.23, which placed a moratorium on using Electroslag Welding (ESW) for weldments on primary structural tension members on bridges. The notice followed the discovery of a fractured flange in a major river crossing structure. That notice effectively eliminated the use of the ESW process from all bridge welding even though the process is allowed by the "AASHTO Standard Specifications for Highway Bridges" for welding compression members.

This project involves conducting workshops and developing guidelines to promote the new Narow Gap Improved Electroslag Welding (NGI ESW) process developed by the Oregon Graduate Institute (OGI) under a FHWA research contract.

NGI ESW is a high-deposition process that has the potential to save significant time and dollars in steel bridge fabrication because it is particularly economical for welding thick materials. The great promise of the process, and because of concern for the safety of welded structures, FHWA initiated research at the Oregon Graduate Institute of Science and Technology, which has now been successfully completed. Equipment, weld consumables, welding procedures, and criteria were developed and proven in laboratory and limited field trials by the OGI researchers. The NGI ESW process, with suggested modifications proposed by the researchers, is now an option and has the potential to improve welding techniques for fabricating heavy weldments.

A 2-day workshop on the new NGI ESW method is under development by the Industrial Research Laboratory (BIRL) at Northwestern University. It will include hands-on welding demonstrations. A total of 18 workshops (two per FHWA region) will be conducted over an 18-month period beginning in late 1995.

Workshop on Electroslag Welding.

U.S. Department of Transportation
Federal Highway Administration


Project Manager
Krishna Verma
(202) 366-4601