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High Cycle Fatigue: A Mechanics of Materials Perspective part 50

High Cycle Fatigue: A Mechanics of Materials Perspective part 50. The nomenclature used in this book may differ somewhat from what is considered standard or common usage. In such instances, this has been noted in a footnote. Additionally, units of measurement are not standard in many cases. While technical publications typically adhere to SI units these days, much of the work published by the engine manufacturers in the United States is presented using English units (pounds, inches, for example), because these are the units used as standard practice in that industry. The graphs and calculations came in those units and no attempt was made to convert. | 476 Appendix A 3 failures of ropes used in working inclines 4 failures of bridges 262 broken rails 12 cases of flooding of permanent way 10 slips in cuttings or embankments and 8 fires in trains. These results indicate that 15.1 of the accidents were due to axle failures. This is consistent with the results quoted by Lardner 5 who indicated that 18 of the accidents were due to axle failures at a much earlier date. Stretton 9 compiled the total number of axles of all descriptions which broke when running during 1878 through 1885. These results are given in Table A.2. He also summarized data for 1883 on the total number of axles in use the number of axles broken when running and the number taken out in shops as flawed. These results are reproduced in Table A.3. Wilson 10 compiled the causes of accidents on British railroads for the period of 1872 through 1875. He indicated that there were 162 133 229 and 478 axles failures during 1872 1873 1874 and 1875 respectively. FATIGUE OF RAILROAD AXLES Apparently the earliest documented research on fatigue of materials was conducted by Albert 21 who performed repetitive tension tests on hoist chains in the mines in the Harz mountains as early as 1828. Poncelet 22 first used the term fatigue in his book Table A.2. Axles broken in eight years 1878-1885 9 Year Engine axles Tender axles Carriage axles Wagon axles Salt van axles Total Crank or driving Leading or trailing 1878 266 21 19 3 221 10 540 1879 248 24 23 3 190 8 496 1880 251 27 25 1 192 18 514 1881 262 21 37 3 200 17 540 1882 242 22 32 2 140 13 451 1883 247 28 21 2 141 11 450 1884 200 23 24 6 113 19 385 1885 190 31 17 4 130 5 377 Table A.3. Engine axles broken or defective 1883 9 Number in use Broken in running with passenger trains Broken in running with goods trains Taken out in shops flawed Crank axles 12 943 70 108 680 Straight axles 1 905 10 19 24 14 848 80 127 704 Appendix A 477 in 1839. According to Smith 23 The spectacular growth of the railroads in the 1830s was .