Experimental study on fatigue behavior of trapezoidal corrugated-web girders based on T-section members

Abstract

Fatigue of steel corrugated-web girders (CWGs) is a new research topic. This study uses trapezoidal corrugated-web T-section members (CWTs) to lower the cost of fatigue tests when investigating the fatigue behavior of a trapezoidal CWG. First, static tests were conducted, and the CWG under a bending moment and CWT under an axial force were compared, which verified that the flanges had the same stress distribution characteristics under equivalent loads. This demonstrates that it is suitable to investigate the fatigue behavior of a CWG using a CWT. Second, fatigue tests were performed on trapezoidal CWT specimens with two different waveform radii, R30 and R60, and their hot spot stress concentration factors at the fatigue critical location of CWG (the intersection between a parallel fold and an inclined fold of a web) were obtained, which reached 1.63 and 1.54, respectively. Of the 18 CWT specimens that experienced fatigue failure, 72 % of the initial cracks occurred at point S, indicating that this location was the most susceptible to fatigue cracking. The same S-N curve (log10N = 12.928-3log10Δσhs) could be applied in calculating the fatigue strengths of CWTs with different wave radii (R30 and R60) when the hot spot stress range that considered the stress concentration factor (SCF) was used.