Now there is a D1 that covers repair, corrective issues, and strengthening of existing steel structures. AWS D1.7/D1.7M, Guide for Strengthening and Repairing Existing Structures, is recommended particularly for the engineer who is obligated under D1.1 Clause 8 to plan for projects that involve strengthening and repairing. Cost is about $100, about 50 pages.

Ross
AWS Marketing