Out-of-Plane Distortion Crack Growth at a Girder Web Gap (Time-Lapse)

<p>[[Video(http://www.youtube.com/watch?v=WJVUS8jtSeI)]]</p>

<p>This video illustrates the growth of a fatigue crack at a detail susceptible to out-of-plane distortion cracking. (Note: Cracking is not observed until after 70,000 cycles are applied.) As expected, once cracking is initiated, growth is relatively fast and accelerates with extension of the crack. During the test, the detail was cycled both in and out of plane (i.e., the loading produced by the actuator resulted in positive and negative applied stresses at the weld toe.) However, only images that recorded the opening of the crack are used to show the extension of the crack.</p>