AWS D1.8/D1.8M:2025 Structural Welding Code — Seismic Supplement, 5th Edition
Buy AWS D1.8/D1.8M:2025 Structural Welding Code — Seismic Supplement, 5th Edition, the current AWS seismic welding code for SFRS design, demand-critical welds, WPS requirements, fabrication, inspectio
About this publication
The AWS D1.8/D1.8M:2025 Structural Welding Code — Seismic Supplement, 5th Edition is the American Welding Society’s specialized structural welding code for welded joints that form part of Seismic Force Resisting Systems (SFRS).
Designed to be used together with AWS D1.1/D1.1M Structural Welding Code — Steel, AWS D1.8 establishes additional requirements for seismic applications where welded steel connections must perform reliably under severe cyclic and inelastic demands associated with earthquakes. AWS states that the code applies to the design, fabrication, quality control, and quality assurance of welded joints designed in conformance with AISC 341, Seismic Provisions for Structural Steel Buildings.
This distinction is critical: AWS D1.8 is not a replacement for AWS D1.1. The requirements of AWS D1.1 continue to apply to designated welds except where D1.8 specifically modifies or supplements them. For seismic steel construction, the two codes work together, with D1.1 providing the general structural steel welding framework and D1.8 adding the specialized provisions needed for seismic performance.
The need for specialized seismic welding requirements grew from lessons learned following damaging earthquakes and subsequent research into the behavior of welded steel moment-frame structures. AWS explains that welded joints expected to undergo significant repetitive inelastic strain need additional controls involving design, detailing, materials, workmanship, testing, inspection, notch toughness, and weld integrity.
The 2025 edition is especially important for structural engineers, steel fabricators, welding engineers, Certified Welding Inspectors, contractors, quality-control personnel, and inspection agencies working on buildings and structures where the designated SFRS is governed by AISC seismic provisions.
AWS D1.8 addresses critical seismic welding topics including demand-critical welds, filler-metal requirements, heat input, WPS requirements, weld access holes, backing removal, protected zones, restoration and repair, continuity plates, doubler plates, inspection, magnetic particle testing, ultrasonic testing, and supplemental qualification requirements.
Demand-critical welding receives particular attention. These welds may experience severe cyclic demands during an earthquake, so the code establishes additional requirements affecting filler-metal mechanical properties, Charpy V-Notch toughness, heat-input envelopes, production lot control, electrode handling, welding procedure variables, and fabrication practices.
The code also contains detailed fabrication provisions. Clause 6 covers subjects such as filler metal and weld metal, demand-critical filler metals, Welding Procedure Specifications, maximum interpass temperature, heat input, bottom-flange welding sequence, weld access holes, tack welding, removal of backing, tab removal, protected zones, and restoration and repair.
Inspection is another major part of AWS D1.8. Clause 7 includes requirements addressing inspection task assignment, inspector qualifications, quality-assurance agency procedures, wide-flange k-area inspection, lamellar tearing, beam copes, weld access holes, repaired locations, magnetic particle testing, and ultrasonic testing.
The 2025 Fifth Edition contains important revisions from AWS D1.8/D1.8M:2021. AWS notes that the new edition has been updated to align more closely with the 2025 edition of AWS D1.1 and current AISC 341 requirements.
Major changes include revised Engineer responsibilities, clarification that a Procedure Qualification Record (PQR) must accompany a WPS qualified by testing where required, updated requirements involving doubler locations and connections, new provisions concerning heat-input limits, alternatives to certain filler-metal production-lot testing, clarification of grinding requirements at weld-access holes, new restoration and repair provisions, and additional AWS A5.18/A5.18M electrode classifications.
The edition also clarifies that welding assemblies used in certain qualification testing may be preset before welding, an update incorporated into Annex A.
AWS D1.8/D1.8M:2025 contains seven principal clauses, seven normative annexes, and extensive commentary. The commentary is nonmandatory but provides valuable technical background and rationale that can help engineers, inspectors, fabricators, and welding professionals interpret the intent behind seismic welding provisions.
At 148 pages, this is a concentrated but highly technical structural welding standard. For projects where AISC 341 seismic requirements apply, D1.8 provides the additional welding controls needed to help ensure that welded connections can deliver the toughness, integrity, and performance expected from a properly designed Seismic Force Resisting System.
Why This Code Matters
AWS D1.8/D1.8M:2025 is a critical reference for professionals involved with welded steel structures designed for seismic resistance, including:
Structural engineers
Seismic design engineers
Welding engineers
AWS Certified Welding Inspectors (CWIs)
Structural steel fabricators
Steel erection contractors
Welding supervisors and coordinators
Quality-control and quality-assurance personnel
Nondestructive testing personnel
Structural steel inspectors
Connection designers
Building officials and special inspectors
Engineering consultants
Welding training and certification programs
Product Features
Official AWS D1.8/D1.8M:2025
Current 5th Edition
Revises AWS D1.8/D1.8M:2021
ANSI-approved American National Standard
Designed specifically for Seismic Force Resisting Systems
Supplements AWS D1.1/D1.1M Structural Welding Code — Steel
Coordinates with AISC 341 Seismic Provisions for Structural Steel Buildings
Covers design, fabrication, quality control, and quality assurance of seismic welded joints
Addresses demand-critical welds
Covers filler-metal mechanical-property requirements
Covers heat-input-envelope requirements
Covers Welding Procedure Specifications and PQR documentation
Addresses continuity plates and doubler plates
Covers weld access holes
Covers backing removal and root treatment
Covers protected zones
Includes restoration and repair provisions
Covers inspector qualifications
Includes magnetic particle testing requirements
Includes ultrasonic testing requirements
Includes supplemental welder qualification for restricted-access welding
Includes supplemental NDT technician qualification requirements
Includes 7 normative annexes
Includes extensive technical commentary
Comprehensive 148-page seismic welding reference
Major 2025 Edition Changes
AWS identifies several important revisions from the 2021 edition:
Engineer responsibilities aligned more closely with AISC 341
Clarified PQR submission requirements for WPSs qualified by testing
Clarified requirements for doubler locations and connections
Clarified qualification requirements for certain welds at hot-rolled shape fillets
Added provisions for heat-input limits
Added an alternative to certain filler-metal production-lot testing
Clarified grinding requirements for notches and grooves in weld access holes
Added new restoration and repair provisions
Added additional AWS A5.18/A5.18M electrode classifications
Clarified that certain welding assemblies may be preset before welding
Product Details
Title: AWS D1.8/D1.8M:2025 Structural Welding Code — Seismic Supplement
Publisher: American Welding Society (AWS)
Edition: 5th
Published: 2025
ANSI Approval Date: February 28, 2025
Number of Pages: 148
Print ISBN: 978-1-64322-358-2
PDF ISBN: 978-1-64322-359-9
Status: Current
Prepared By: AWS D1 Committee on Structural Welding
Supersedes: AWS D1.8/D1.8M:2021
Companion Code: AWS D1.1/D1.1M Structural Welding Code — Steel
Referenced Seismic Standard: AISC 341