AWS D1.7/D1.7M

This document contains basic information pertinent to the weldedstrengthening and repair of existing steel structures. Theinformation contained in this guide is intended for both Engineersand Contractors with the purpose of providing direction andguidance to perform weld repairs, weld strengthening, and otherweld procedures to correct problematic issues with existingstructures. This guide contains background information that will beuseful to the Engineer who is obligated under AWS D1.1/D1.1M:2008Clause 8 to provide a comprehensive plan to address projects thatinvolve strengthening and repairing of steel structures. Theapproach to the strengthening and repairing of these materials isto be developed using the information provided herein.

This guide is intended to apply to the strengthening and repairof existing structures made of the following materials:

(1) Steel with a minimum specified yield strength of 100 ksi[690 MPa] or less

(2) Cast iron

(3) Wrought iron

Strengthening or repairing an existing structure includesmodifications to meet new serviceability or load requirements aswell as corrections made to repair conditions unsuitable for futureuse specified by the Engineer. The Engineer should prepare acontract for the work including, but not limited to, design,workmanship, inspection, acceptance criteria, and documentation.Except as modified in this clause, provisions of this guide shouldapply to the strengthening and repair of existing structures,including heat straightening of distorted members.

Limitations. This guide is intended to assistin the evaluation of existing structural elements and thedevelopment of appropriate procedures for repairing those elements.It does not provide exhaustive coverage of any specific topic.

This guide is intended to apply to the strengthening and repairof existing buildings and other structural systems. It is notintended to apply to:

(1) Structures made of steels less than 1/8 in [3 mm] thick

(2) Pressure vessels and pressure piping

(3) Structures made of materials other than those listed underthe scope

(4) Seismic upgrades

(5) New construction

Whereas this guide is not intended to apply the applicationoutside the scope, the principles contained in this guide may beapplied to other materials and applications. The Engineer isadvised to use caution and engineering judgment for applicationoutside the scope of this guide.

More importantly, it is critical to state here that thisdocument does not provide detailed specific procedures anddirection to correct any specific strengthening or repair operationregardless of how common or standard the procedure may be. Instead,information supplied herein as well as that material referenced inAnnex A is intended to provide users with an overall approach toweld modifications as they pertain to: strengthening and repair;technical resources to develop appropriate detailed specificstrengthening and repair contract documents or procedures;summarized guidance on typical weldability of common metals;summarized guidance for testing the serviceability of theprocedures and a summary of common procedures and approaches thatare intended to be modified for the specific procedure.

Approval. All references to “approval” shouldbe interpreted to mean approval by the Engineer.

Safety Precautions. Safety and health issuesand concerns are beyond the scope of this standard and thereforeare not fully addressed herein. However, in addition to thematerial supplied in subsequent chapters of this document,pertinent information can be found in the following standalonedocuments: ANSI Z49.1, Safety in Welding, Cutting, and AlliedProcesses, and applicable federal, state, and localregulations. Other pertinent information can be found in themanufacturer’s safety literature on equipment and materials. Thesedocuments should be referred to and followed as required.

NOTE: This guide may involve hazardous materials,operations, and equipment. The document does not purport to addressall of the safety problems associated with its use. It is theresponsibility of the user to establish appropriate safety andhealth practices. The user should determine the applicability ofany regulatory limitations prior to use.

Standard Units of Measure. This guide makes useof both U.S. Customary Units and the International System of Units(SI). The latter are shown within brackets ([ ]) or in appropriatecolumns in tables and figures. The measurements may not be exactequivalents; therefore, each system should be used independently ofthe other.

Edition:

10

Published:

01/01/2010

ANSI:

ANSI Approved

Number of Pages:

54

File Size:

1 file , 330 KB