On the Fatigue Strength of Welded High-Strength Steel Joints in the As-Welded, Post-Weld-Treated and Repaired Conditions in a Typical Ship Structural Detail

被引:8
作者
Ahola, Antti [1 ]
Lipiainen, Kalle [1 ]
Lindroos, Juuso [2 ]
Koskimaki, Matti [1 ]
Laukia, Kari [2 ]
Bjork, Timo [1 ]
机构
[1] LUT Univ, Lab Steel Struct, Yliopistonkatu 34, FI-53850 Lappeenranta, Finland
[2] Aker Arctic Technol Oy, Merenkulkijankatu 6, FI-00980 Helsinki, Finland
关键词
fatigue; welded joint; ship structure; post-weld treatment; weld repair; high-strength steel; QUALITY CRITERIA; STRESSES; BEHAVIOR; THIN;
D O I
10.3390/jmse11030644
中图分类号
U6 [水路运输]; P75 [海洋工程];
学科分类号
0814 ; 081505 ; 0824 ; 082401 ;
摘要
Weld quality and life extension methods of welded details in ship structures made of high-strength and ultra-high-strength steels are of high importance to overcome the issues related to the fatigue characteristics of welded high-strength steels. The current work experimentally and numerically investigated the fatigue strength of a longitudinal stiffener detail, typically present in the bulkhead connections of ship hull. Two high-strength steel grades, namely EQ47TM and EQ70QT steels, were studied in welded plate connections using gas metal arc welding with rutile-cored wires. Fatigue tests were carried out on both small-scale specimens under axial and large-scale beam specimens under four-point bending loading. In addition to the joints tested in the as-welded condition, the high-frequency mechanical impact (HFMI) treatment was considered as a post-weld treatment technique in the fatigue test series. Furthermore, the large-scale beam specimens were pre-fatigued until substantial fatigue cracks were observed, after which they were re-tested after weld repairing and post-weld treatments to investigate the potential to rehabilitate fatigue-cracked ship details. The joints in the as-welded condition were performed in accordance with the current design recommendations. Due to the severe transition from the base material to the weld reinforcement in the joints welded with the rutile-cored wire, a successful HFMI treatment required geometrical modification of weld toe using a rotary burr to avoid any detrimental sub-cracks at the HFMI-treated region. Alternatively, the use of solid filler wires could potentially overcome these issues related to the welding quality. Repaired and post-weld-treated welds performed well in the re-tests, and the fatigue strength was almost twice higher than that of tests in the as-welded condition.
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页数:15
相关论文
共 31 条
[1]   Fatigue strength of misaligned non-load-carrying cruciform joints made of ultra-high-strength steel [J].
Ahola, A. ;
Bjork, T. .
JOURNAL OF CONSTRUCTIONAL STEEL RESEARCH, 2020, 175
[2]  
Ahola A., 2022, P 8 INT C STRUCT ENG, P1130
[3]  
Ahola A., 2020, THESIS LUT U LAPPEEN
[4]   Fatigue life extension of existing welded structures via high frequency mechanical impact (HFMI) treatment [J].
Al-Karawi, Hassan ;
Polach, Ruediger U. Franz von Bock und ;
Al-Emrani, Mohammad .
ENGINEERING STRUCTURES, 2021, 239
[5]  
[Anonymous], 2016, DNVGL-RP-C203
[6]  
[Anonymous], HIFIT HIFIT PROCESS
[7]  
[Anonymous], 2005, Eurocode 3: Design of steel structures - Part 1-1: General rules and rules for buildings
[8]   Influence of weld geometry and residual stresses on the fatigue strength of longitudinal stiffeners [J].
Baumgartner, J. ;
Bruder, T. .
WELDING IN THE WORLD, 2013, 57 (06) :841-855
[9]  
Billingham J., 2003, Review of the Performance of High Strength Steels Used Offshore
[10]   The need for a weld quality system for fatigue loaded structures [J].
Björk T. ;
Samuelsson J. ;
Marquis G. .
Welding in the World, 2008, 52 (1-2) :34-46