1. For a bolted assembly with six bolts, the stiffness of each bolt is k» = 3 Mlbf/in and the stiffness of the members is km = 12 Mlbf/in per bolt. An external load of 80 kips is applied to the entire joint. Assume the load is equally distributed to all the bolts. It has been determined to use 1/2 in-13 UNC grade 8 bolts with rolled threads. Assume a torque co-efficient of K = 0.2. a. Determine the maximum bolt preload that can be applied without exceeding the proof strength of the bolts. b. Determine the minimum bolt preload that can be applied while avoiding joint separation. c. Determine the value of torque in units of Ibf-ft that should be specified for preloading the bolts if it is desired to preload to 75% of the proof load. d. Determine the yielding factor of safety for part c). (based on proof strength)

1. For a bolted assembly with six bolts, the stiffness of each bolt is k» = 3 Mlbf/in and the stiffness of the members is km = 12 Mlbf/in per bolt. An external load of 80 kips is applied to the entire joint. Assume the load is equally distributed to all the bolts. It has been determined to use 1/2 in-13 UNC grade 8 bolts with rolled threads. Assume a torque co-efficient of K = 0.2. a. Determine the maximum bolt preload that can be applied without exceeding the proof strength of the bolts. b. Determine the minimum bolt preload that can be applied while avoiding joint separation. c. Determine the value of torque in units of Ibf-ft that should be specified for preloading the bolts if it is desired to preload to 75% of the proof load. d. Determine the yielding factor of safety for part c). (based on proof strength)

Mechanics of Materials (MindTap Course List)

9th Edition

ISBN:9781337093347

Author:Barry J. Goodno, James M. Gere

Publisher:Barry J. Goodno, James M. Gere

Chapter2: Axially Loaded Members

Section: Chapter Questions

Problem 2.2.11P: A small lab scale has a rigid L-shaped frame ABC consisting of a horizontal arm AB (length b = 10...

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