Evaluation and Repair of Wrought Iron and - Purdue e-Pubs ...

5310 in Figure 3.21. Two Measurements Group CEA-06-125UN-350 type strain gageswere also placed on the side (thickness) of the eyebar connection – Gages 7 and 8 inFigure 3.21. Figure 3.22 shows one of the eyebar connections after the strain gages wereattached.A fixture was manufactured to load the eyebar connection test sample. Thisfixture consisted of three thick steel plates that were bolted together. The dimensions ofthe plates were determined so that yielding would not occur in the plates prior to failureoccurring in the eyebar connection. The middle plate was inserted into the MTS machinewhile the other two plates extended down to the eye connection detail. These two plateshad holes that were 2 ¼ inch in diameter, similar to the eye connection detail.A large pin, 2 3 / 16 inch diameter steel rod, was inserted through all three holes andthe eyebar connection was therefore connected to the test fixture. The shank of the eyeconnection was then placed in the second lower grip of the MTS testing machine. Figure3.23 is a photograph of the test fixture and eyebar connection in place in the MTS testingmachine. After the eyebar connection was placed into the MTS testing machine a twoinch extensometer was attached to the shank of the eyebar above the lower grips of theMTS testing machine with some very tight elastic bands. Then the strain gages, load cell,stroke crosshead, and extensometer were attached to the data acquisition scanner forrecording.Similar to the tensile coupon testing procedure, two tests were completed on theeye connection. In the initial test, the specimen was loaded only in the elastic region ofthe stress strain curve with the load applied at a fixed rate of five thousand pounds perminute. The readings from the strain gages, extensometer, load cell and stroke werecontinuously recorded during this test. The sample was only stressed until a stress of 12ksi or less was reached in the shank of the specimen. Again, the low stress limit used forthis test was to ensure that the specimen was never taken out the elastic region forwrought iron and permanent deformations were never created.