Extremely Low-Cycle Fatigue Tests of Thick-Walled Steel Bridge Piers

To study extremely low-cycle fatigue performance of steel bridge structures, a total of nine steel bridge piers with unstiffened thick-walled box sections were tested in this study. The effects of various parameters, including cross-sectional shape (with or without an extension part), loading pattern, and width-thickness and slenderness ratios were investigated. Experimental results demonstrate that ductile cracks occurred at the column base in all specimens regardless of cyclic-loading histories and that ductile crack initiation life is sensitive to loading pattern, cross-sectional shape, and the width-thickness ratio. In all tests, the ductile crack began in the pier-to-base weld, and subsequent cyclic loads resulted in the ductile cracks growing at the weld toes along web and flange directions and then propagating into the base metal, which triggered an obvious decrease in strength capacity. A significant delay was observed between ductile crack initiation and maximum strength capacity. Moreover, ductile crack initiation and propagation may be accompanied by local buckling.

[1]  Frieder Seible,et al.  CYCLIC TESTING OF BUILT-UP STEEL SHEAR LINKS FOR THE NEW BAY BRIDGE , 2003 .

[2]  H. Ge,et al.  ULTIMATE STRAINS OF STRUCTURAL STEELS AGAINST DUCTILE CRACK INITIATION , 2007 .

[3]  Gaetano Manfredi,et al.  The use of damage functionals in earthquake engineering: A comparison between different methods , 1993 .

[4]  Leroy Gardner,et al.  Extremely low cycle fatigue tests on structural carbon steel and stainless steel , 2010 .

[5]  M. A. Wahab,et al.  Extremely Low Cycle(ELC) Fatigue Cracking Behaviour in Steel Bridge Rigid Frame Piers (耐震・免震・制震構造と地震防災システムの構築プロジェクト) , 2001 .

[6]  Hanbin Ge,et al.  Stiffened steel box columns. Part 1: Cyclic behaviour , 2000 .

[7]  Masatoshi Kuroda,et al.  Extremely low cycle fatigue life prediction based on a new cumulative fatigue damage model , 2002 .

[8]  George C. Lee,et al.  Low-Cycle Bending-Fatigue Strength of Steel Bars under Random Excitation. Part I: Behavior , 2005 .

[9]  Masahiro Sakano,et al.  LOW CYCLE FATIGUE BEHAVIOR OF STEEL PIER BEAM-COLUMN JOINT , 1997 .

[10]  Jun Iyama,et al.  EFFECTS OF MATERIAL TOUGHNESS AND PLATE THICKNESS ON BRITTLE FRACTURE OF STEEL MEMBERS , 2003 .

[11]  Tsutomu Usami,et al.  Damage Evaluation in Steel Box Columns by Pseudodynamic Tests , 1996 .

[12]  L. Xue.  A unified expression for low cycle fatigue and extremely low cycle fatigue and its implication for monotonic loading , 2008 .

[13]  Hiroshi Akiyama,et al.  Brittle fracture under repeated high stresses , 1994 .

[14]  Hanbin Ge,et al.  A PERFORMANCE-BASED SEISMIC DESIGN METHODOLOGY FOR STEEL BRIDGE SYSTEMS , 2009 .

[15]  Hitoshi Kuwamura,et al.  Transition between Fatigue and Ductile Fracture in Steel , 1997 .

[16]  Hitoshi Kuwamura,et al.  Ductile Crack as Trigger of Brittle Fracture in Steel , 1997 .

[17]  Gregory G. Deierlein,et al.  Validation of Cyclic Void Growth Model for Fracture Initiation in Blunt Notch and Dogbone Steel Specimens , 2008 .

[18]  Gregory G. Deierlein,et al.  Effect of weld details on the ductility of steel column baseplate connections , 2009 .

[19]  Gregory G. Deierlein,et al.  Experimental Investigation of Inelastic Cyclic Buckling and Fracture of Steel Braces , 2009 .