461_Mechanics SolutionInstructors_Sol.Manual-Mechanics_Materials_7e.book_Gere_light.1

461_Mechanics SolutionInstructors_Sol.Manual-Mechanics_Materials_7e.book_Gere_light.1

Info iconThis preview shows page 1. Sign up to view the full content.

View Full Document Right Arrow Icon
This is the end of the preview. Sign up to access the rest of the document.

Unformatted text preview: 05Ch05.qxd 9/25/08 2:29 PM Page 455 SECTION 5.9 Shear Stresses in Circular Beams Solution 5.9-3 b b p Wind load on a sign (b) REQUIRED DIAMETER BASED UPON SHEAR STRESS width of sign 10 ft 75 lb/ft2 7500 psi 2000 psi sallow tallow d diameter t d 10 W t wind force on one pole b ph2 a b 2 W 1875 lb r1 W a h1 + h2 b 2 p (d 4 64 2 d24) d2 d d1 I p4 cd 64 4d 4 a bd 5 pd 4 369 a b 64 625 d 2t d 2 s Mc I d3 (d M(d/2) d 2 d 10 r2 + r1 t p2 cd 4 A p2 (d2 4 100 4V 61 a ba b 3 41 9pd2 3 10.52 in. ; Problem 5.9-4 Solve the preceding problem for a sign and poles having the following dimensions: h1 6.0 m, h2 1.5 m, b 3.0 m, and t d/10. The design wind pressure is 3.6 kPa, and the allowable stresses in the aluminum are 50 MPa in bending and 14 MPa in shear. d2) 1 r2 d 2 2d 5 d a 4d 2 bd 5 7.0160 V d2 7.0160 Vmax tallow (7.0160)(1875 lb) 2000 psi 17.253 M 369pd /40,000 d (17.253)(506,250 lb-in.) 17.253 Mmax sallow 7500 psi d b d2 2d 2 a b +a b 2 5 d2 4 1164.6 in. 2 t inches) 3 2 4 d 5 369pd 4 (in.4) 40,000 c d 2 + r2r1 + r12 r2 2 + r1 2 2d 2 d 2d d2 a b + a ba b + a b 2 2 5 5 506,250 lb-in. I 4V a 3A 1875 lb r22 r2 + r2r1 + r2 2 1 (a) REQUIRED DIAMETER BASED UPON BENDING STRESS Mmax W Vmax 2.56 in. ; (Bending stress governs.) 6.5775 in.2 61 41 9pd2 100 455 ...
View Full Document

This note was uploaded on 12/22/2011 for the course MEEG 310 taught by Professor Staff during the Fall '11 term at University of Delaware.

Ask a homework question - tutors are online