Application studies for fatigue strength improvement of welded structures by high-frequency mechanical impact (HFMI) treatment. (1st January 2016)

• Record Type: Journal Article
• Authors: Yıldırım, Halid Can; Leitner, Martin; Marquis, Gary B.; Stoschka, Michael; Barsoum, Zuheir
• Is Part Of: Engineering structures. Volume 106(2016:Jan. 01)
• Page Start: 422
• Page End: 435
• Publication Date: 2016-01-01
• Subjects: High-frequency mechanical impact (HFMI) -- Large-scale structures -- Fatigue strength improvement -- High-strength steels -- Light-weight design; Structural engineering -- Periodicals; Structural analysis (Engineering) -- Periodicals; Construction, Technique de la -- Périodiques; Génie parasismique -- Périodiques; Pression du vent -- Périodiques; Earthquake engineering; Structural engineering; Wind-pressure; Periodicals; 624.105
• DOI: 10.1016/j.engstruct.2015.10.044
• Languages: English
• ISSNs: 0141-0296

Abstract

Graphical abstract: Highlights: HFMI-treated welded structures are presented with previously proposed design curves. 62 weld details of large-scale complex structures are extracted from the literature. Fatigue testing of 23 cover-plates is carried out for the use of crane industry. Proposed design curves based on f y are conservative with respect to fatigue data. Abstract: In 2013, a new guideline for the design of high-frequency mechanical impact (HFMI) treatment was drafted. The proposed design curves were made based on the fatigue data of axially-loaded welded joints which were manufactured from high-strength steels. All the S–N curves were shown to be conservative with respect to the existing fatigue data for laboratory-scale specimens of longitudinal, transverse, and butt welds. In reality, structures in civil, offshore, mechanical engineering and ship industries generally include large-scale and more complicated components rather than laboratory-scale specimens. Therefore, this paper firstly presents the validation of design proposals by considering fatigue data sets for large-scale welded structures. In total, 62 fatigue data points for bridge, crane and beam-like components are reported, in which the yield strength varies from 250 to 725 MPa, and stress ratio varies from −1 to 0.56. Validations are then extended also for cover plates by performing fatigue tests of 23 weld details both in as-welded and HFMI-treated cases for the use of crane industry. Both the extracted and obtained fatigue data are found to be in good agreement with the previously-proposed design guidelines for nominal and effective notch stress assessment.