Evaluation and Repair of Wrought Iron and - Purdue e-Pubs ...
Evaluation and Repair of Wrought Iron and - Purdue e-Pubs ... Evaluation and Repair of Wrought Iron and - Purdue e-Pubs ...
56completed, but before the surface was ground flush to make the welds blend into theoriginal eyebar connection.Eyebar B was modeled to be a worst case scenario of section loss due to corrosionin an eyebar end connection. In this eyebar, half the thickness of the original eyebar’smaterial was removed from the center two and a half inches around the hole andperpendicular to the direction of loading. Figure 3.28 shows Eyebar B after this materialwas removed and prepared for welding.Once this material was removed, the area simulating corrosion needed to be filledwith weld material. To do this an E7024 SMAW 1/8” diameter welding rod was utilizedwith a DC reverse polarity electric source, similar to Eyebar A. An initial pass aroundthe hole in the eyebar and along the open edges were placed to create a dam for the fillermaterial, as can been seen in Figure 3.29.Once the initial passes were placed, filler passes were then placed in the open areain the direction of loading of the eyebar to reduce heat distortion. In between passes thetemperature of the base metal was also monitored to ensure the metal was not to hot toweld and to reduce the amount of heat distortion in the metal. It was necessary to takebreaks and allow the metal cool between sets of passes. The welds were also cleanedusing a chisel hammer and wire brush in between each pass. Figures 3.30 and 3.31 showthe eyebar end connection after all the welding was completed.As can been seen in Figure 3.31 there was a slight amount of heat distortion andcurvature in the wrought iron eyebar connection from the filler weld. To straighten thispiece, the eyebar was heated until it was red hot, as seen in Figure 3.32, and thenstraightened by striking the eyebar with large hammer. The color of the eyebar wassimilar to the color of the iron that was heat straightened in the tension testing couponsand therefore at the adequate temperature to straighten the iron without inducing
57significant strain damage in the metal. The eyebar was then allowed to cool slowly andthen surface ground to make the filler weld blend into the original eyebar.After surface grinding to a flush condition, Measurements Group CEA-06-250UN-350 type strain gages were placed on both faces of the shank of the eyebarconnections of Eyebars A and B. Figures 3.33 and 3.34 are photographs of the eyebarsafter being surface ground and directly before testing. The same fixture that was utilizedwith the MTS testing machine when testing the eyebar connection that had not beenrepaired was also used in testing Eyebar A and B.This fixture, which consisted of three thick plates that were bolted together, wasplaced in the upper grip of the testing machine. A 2 3 / 16 inch steel pin was placed throughtwo of these plates and hole in the eyebars. The bottom of the eyebar was then placed inthe bottom grip of the MTS testing machine. A two inch extensometer was then attachedat the shank of the eyebar connection above the lower grip with strong elastic bands.Figures 3.35 and 3.36 are front and side view photographs of Eyebar A immediatelybefore testing.The eyebar connections were then tested in the same manner than the eyeconnections that had not experienced any repair. The eye connections were initiallyloaded only in the elastic region of the stress-strain curve. In this test, load was applied ata fixed rate while the amount of strain in the specimen was recorded. The readings fromthe strain gages, extensometer, load cell and stroke were recorded during this test. Thistest was done at a rate of five thousand pounds per minute. The sample was only stresseduntil a stress of 10 ksi or less was reached in the shank of the specimen. This test wascompleted to ensure that the testing and data recording equipment was working properly.After the initial test, both Eyebar A and B were loaded completely until failure.The eye connections were pulled at a constant rate of 1/12 inch per minute until failure.The failure location of the eye connections was recorded along with the strain gage
- Page 26 and 27: 62. LITERATURE SEARCHBefore experim
- Page 28 and 29: 8imperfections, the performance of
- Page 30 and 31: 10wrought iron. Adding the slag aft
- Page 32 and 33: 12method for manufacturing wrought
- Page 34 and 35: 14patents for their process and tra
- Page 36 and 37: 16This method of testing of structu
- Page 38 and 39: 18plot of this percent elongation d
- Page 40 and 41: 20significant variation in the perc
- Page 42 and 43: 22The practice of restoring histori
- Page 44 and 45: 24Elleby, Wallace W. Sanders, F. Wa
- Page 46 and 47: 26From all the surveys that were di
- Page 48 and 49: 28Table 2.1 Average Ultimate Streng
- Page 50 and 51: 30Figure 2.3 Wrought Iron “Sponge
- Page 52 and 53: 32Histogram of Kirkaldy Wrought Iro
- Page 54 and 55: 34Percent Occurance in Range - %45.
- Page 56 and 57: 3660Combined Wrought Iron BarsTensi
- Page 58 and 59: 38The Bell Ford Bridge consisted of
- Page 60 and 61: 40Two. These samples were taken fro
- Page 62 and 63: 42specimens were of constant cross
- Page 64 and 65: 44Along with rectangular tensile co
- Page 66 and 67: 46After the initial test loading wa
- Page 68 and 69: 483.6 Fatigue TestingTo develop a b
- Page 70 and 71: 50The final specimen category consi
- Page 72 and 73: 52This analysis was completed using
- Page 74 and 75: 54After the initial test was comple
- Page 78 and 79: 58readings, load cell readings and
- Page 80 and 81: 60Figure 3.3 Donated Eyebars 4 and
- Page 82 and 83: 62Figure 3.7 Heated Areas in Blue o
- Page 84 and 85: 64Figure 3.11 Detail Used in Groove
- Page 86 and 87: 66900080007000y = 27.153xR 2 = 0.99
- Page 88 and 89: 68Figure 3.19 Charpy Impact Testing
- Page 90 and 91: 70Figure 3.23 Eyebar Connection in
- Page 92 and 93: 72Figure 3.27 Eyebar A After Filler
- Page 94 and 95: 74Figure 3.31 Side View of Finished
- Page 96 and 97: 76Figure 3.35 Front View of Eyebar
- Page 98 and 99: 78strength from the existence of pe
- Page 100 and 101: 80The carbon content present in the
- Page 102 and 103: 82value may not be very accurate bu
- Page 104 and 105: 84strengths was found to be 29,940
- Page 106 and 107: 86wrought iron bars were investigat
- Page 108 and 109: 88stresses are induced. These perma
- Page 110 and 111: 90toughness the material. The test
- Page 112 and 113: 92From the finite element analysis,
- Page 114 and 115: 94Table 4.1 Chemical Analysis of Ey
- Page 116 and 117: 96Table 4.3 Tensile Coupon Test Res
- Page 118 and 119: 98Table 4.5 Charpy Impact Test Resu
- Page 120 and 121: 100Table 4.7 Comparison of Strain G
- Page 122 and 123: 102Figure 4.1 Typical Micrograph of
- Page 124 and 125: 104Figure 4.5 Fracture Surface of D
57significant strain damage in the metal. The eyebar was then allowed to cool slowly <strong>and</strong>then surface ground to make the filler weld blend into the original eyebar.After surface grinding to a flush condition, Measurements Group CEA-06-250UN-350 type strain gages were placed on both faces <strong>of</strong> the shank <strong>of</strong> the eyebarconnections <strong>of</strong> Eyebars A <strong>and</strong> B. Figures 3.33 <strong>and</strong> 3.34 are photographs <strong>of</strong> the eyebarsafter being surface ground <strong>and</strong> directly before testing. The same fixture that was utilizedwith the MTS testing machine when testing the eyebar connection that had not beenrepaired was also used in testing Eyebar A <strong>and</strong> B.This fixture, which consisted <strong>of</strong> three thick plates that were bolted together, wasplaced in the upper grip <strong>of</strong> the testing machine. A 2 3 / 16 inch steel pin was placed throughtwo <strong>of</strong> these plates <strong>and</strong> hole in the eyebars. The bottom <strong>of</strong> the eyebar was then placed inthe bottom grip <strong>of</strong> the MTS testing machine. A two inch extensometer was then attachedat the shank <strong>of</strong> the eyebar connection above the lower grip with strong elastic b<strong>and</strong>s.Figures 3.35 <strong>and</strong> 3.36 are front <strong>and</strong> side view photographs <strong>of</strong> Eyebar A immediatelybefore testing.The eyebar connections were then tested in the same manner than the eyeconnections that had not experienced any repair. The eye connections were initiallyloaded only in the elastic region <strong>of</strong> the stress-strain curve. In this test, load was applied ata fixed rate while the amount <strong>of</strong> strain in the specimen was recorded. The readings fromthe strain gages, extensometer, load cell <strong>and</strong> stroke were recorded during this test. Thistest was done at a rate <strong>of</strong> five thous<strong>and</strong> pounds per minute. The sample was only stresseduntil a stress <strong>of</strong> 10 ksi or less was reached in the shank <strong>of</strong> the specimen. This test wascompleted to ensure that the testing <strong>and</strong> data recording equipment was working properly.After the initial test, both Eyebar A <strong>and</strong> B were loaded completely until failure.The eye connections were pulled at a constant rate <strong>of</strong> 1/12 inch per minute until failure.The failure location <strong>of</strong> the eye connections was recorded along with the strain gage
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