5 (a) A steel bar is subjected to a sequence of completely reversed stress cycles which vary over a 20 second time period as follows: Five tycles at 570 N/mm, two cycles at 630 N/mm2 and one cycle at 700 N/mm?. The corresponding lives for the above stresses are 10°, 3.8 x 10* and 1.6 x 10* cycles. The endurance limit of the steel used is 430 N/mm?. Evaluate the fatigue life of the bar for the given repeating sequence of loading.

5 (a) A steel bar is subjected to a sequence of completely reversed stress cycles which vary over a 20 second time period as follows: Five tycles at 570 N/mm, two cycles at 630 N/mm2 and one cycle at 700 N/mm?. The corresponding lives for the above stresses are 10°, 3.8 x 10* and 1.6 x 10* cycles. The endurance limit of the steel used is 430 N/mm?. Evaluate the fatigue life of the bar for the given repeating sequence of loading.

Mechanics of Materials (MindTap Course List)

9th Edition

ISBN:9781337093347

Author:Barry J. Goodno, James M. Gere

Publisher:Barry J. Goodno, James M. Gere

Chapter8: Applications Of Plane Stress (pressure Vessels, Beams, And Combined Loadings)

Section: Chapter Questions

Problem 8.2.7P: (a) Solve part (a) of the preceding problem if the pressure is 8.5 psi, the diameter is 10 in., the...

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