Bending huge steel girders. Washington, D.C., Sept. 23. At the U.S. Bureau of Standards officials were witnessing the testing of rigid steel frame knees that are used in grade eliminations such as over-passes, under-passes, bridges, etc. This photo shows the girder or knee placed into the huge 600,000 lb. testing machine in preparation for the test. This welded rigid steel frame knee which was designed to withstand 50,000 pounds had a maximum load of 153,600 lbs placed on it before it buckled.
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Harris &amp; Ewing, photographer</div>
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