518_Mechanics SolutionInstructors_Sol.Manual-Mechanics_Materials_7e.book_Gere_light.1

518_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: 06Ch06.qxd 9/24/08 512 5:32 AM Page 512 CHAPTER 6 Stresses in Beams (Advanced Topics) Solution 6.3-4 Composite beam SIMPLE BEAM: L 4.0 m q 50 kN/m nb qL2 100 kN # m 8 (1) Wood beam: b 150 mm Mmax Ew (19) (150 mm) 2850 mm All dimensions in millimeters. h1 250 mm IT 11 GPa (2) Steel plates: b 150 mm t h2 350 mm Es TRANSFORMED SECTION (WOOD) Width of steel plates 1 (2850 12 150)(250)3 6.667 * 109 mm4 50 mm 209 GPa 1 (2850)(350)3 12 MAXIMUM STRESS IN THE WOOD (1) (EQ. 6-15) sw s1 Mmax(h1/2) IT ; 1.9 MPa MAXIMUM STRESS IN THE STEEL (2) (EQ. 6-17) ss s2 Mmax(h2/2)n IT ; 49.9 MPa Wood beam is not changed. n Es Ew 209 11 19 Problem 6.3-5 The cross section of a beam made of thin strips of aluminum separated by a lightweight plastic is shown in the figure. The beam has width b 3.0 in., the aluminum strips have thickness t 0.1 in., and the plastic segments have heights d 1.2 in. and 3d 3.6 in. The total height of the beam is h 6.4 in. The moduli of elasticity for the aluminum and plastic are Ea 11 106 psi and Ep 440 103 psi, respectively. Determine the maximum stresses sa and sp in the aluminum and plastic, respectively, due to a bending moment of 6.0 k-in. y t z d C 3d d Probs. 6.3-5 and 6.3-6 b h 4t 5d ...
View Full Document

Ask a homework question - tutors are online