The test rig is shown in the previous image.
From the same project as the previous 3 images
This image is from:
Angelina Jay, Fariborz Mirzaie, Andrew Myers, Shahabeddin Torabian, Abdullah Mahmoud, Eric Smith and Benjamin Schafer, “The effect of geometric imperfections on the flexural buckling strength of tapered spirally welded steel tubes, Proceedings of the Annual Stability Conference Structural Stability Research Council (SSRC), Orlando, Florida, April 12-15, 2016
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