Fei Xu , Yun Zhao , Xuhong Zhou , Xudong Qian , Qingshan Yang , Jun-Zhi Liu
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引用次数: 0
Abstract
This paper presents an experimental study on the fatigue behaviour of circular hollow section (CHS) gap K-joints subjected to accelerated electrochemical corrosion. A total of four specimens were examined, comprising three corroded joints and one reference joint, all subjected to cyclic axial loading applied to the chord member, which induced corresponding axial loads in the braces. Prior to fatigue testing, a full-immersion accelerated electrochemical corrosion process was conducted. The surface morphologies of the corroded joints were captured using a high-resolution 3D scanner, and the corrosion characteristics were quantitatively analysed. Fatigue behaviour was assessed at three critical stages, i.e., first visible crack detection (fatigue life N2), development of a through-thickness crack (fatigue life N3), and end of the test (fatigue life N4). Test results revealed that the corroded surfaces exhibited a mixed pattern of general and pitting corrosion, with the maximum pit depth reaching 0.32 mm at the chord crown toe. Crack initiation predominantly occurred in areas of severe corrosion near the maximum stress concentration. At lower fatigue stress amplitudes, corrosion significantly reduced fatigue life N4, while at higher amplitudes, the stress amplitude became the dominant factor. The corroded joints exhibited a gradual accumulation of damage, culminating in sudden failure, which provides less warning compared with non-corroded joints. The existing Sr,hs-N curves in guidelines may overestimate the fatigue life of corroded joints when compared with the experimental database collected from this study and literature. Consequently, Sr,hs-N curves for CHS joints in corrosive environments were developed using multiple linear regression analysis, accounting for the interaction between wall thickness and corrosion fatigue life.
期刊介绍:
Engineering Structures provides a forum for a broad blend of scientific and technical papers to reflect the evolving needs of the structural engineering and structural mechanics communities. Particularly welcome are contributions dealing with applications of structural engineering and mechanics principles in all areas of technology. The journal aspires to a broad and integrated coverage of the effects of dynamic loadings and of the modelling techniques whereby the structural response to these loadings may be computed.
The scope of Engineering Structures encompasses, but is not restricted to, the following areas: infrastructure engineering; earthquake engineering; structure-fluid-soil interaction; wind engineering; fire engineering; blast engineering; structural reliability/stability; life assessment/integrity; structural health monitoring; multi-hazard engineering; structural dynamics; optimization; expert systems; experimental modelling; performance-based design; multiscale analysis; value engineering.
Topics of interest include: tall buildings; innovative structures; environmentally responsive structures; bridges; stadiums; commercial and public buildings; transmission towers; television and telecommunication masts; foldable structures; cooling towers; plates and shells; suspension structures; protective structures; smart structures; nuclear reactors; dams; pressure vessels; pipelines; tunnels.
Engineering Structures also publishes review articles, short communications and discussions, book reviews, and a diary on international events related to any aspect of structural engineering.