A horizontal shelf AD of length L = 1215 mm, width b= 305 mm, and thickness t= 22 mm is supported by brackets at B and C (see part a of Figure 1). The brackets are adjustable and may be placed in any desired positions between the ends of the shelf. A uniform load of intensity q, which includes the weight of the shelf itself, acts on the shelf (see part b of Figure 1). L. (a) Determine the maximum permissible value of the load q if the allowable bending stress in the shelf is 8.5 MPa and the position of the supports is adjusted for maximum load carrying capacity. D В C %3! Oallow (b) Hint: Find the spacing x between the two supports, such that the maximum and minimum bending moments are equal in absolute value. Figure 1. © 2013 Cengage Learning Engineering. All Rights Reserved D)

A horizontal shelf AD of length L = 1215 mm, width b= 305 mm, and thickness t= 22 mm is supported by brackets at B and C (see part a of Figure 1). The brackets are adjustable and may be placed in any desired positions between the ends of the shelf. A uniform load of intensity q, which includes the weight of the shelf itself, acts on the shelf (see part b of Figure 1). L. (a) Determine the maximum permissible value of the load q if the allowable bending stress in the shelf is 8.5 MPa and the position of the supports is adjusted for maximum load carrying capacity. D В C %3! Oallow (b) Hint: Find the spacing x between the two supports, such that the maximum and minimum bending moments are equal in absolute value. Figure 1. © 2013 Cengage Learning Engineering. All Rights Reserved D)

Mechanics of Materials (MindTap Course List)

9th Edition

ISBN:9781337093347

Author:Barry J. Goodno, James M. Gere

Publisher:Barry J. Goodno, James M. Gere

Chapter5: Stresses In Beams (basic Topics)

Section: Chapter Questions

Problem 5.6.20P

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