404_Mechanics SolutionInstructors_Sol.Manual-Mechanics_Materials_7e.book_Gere_light.1

404_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 9/24/08 398 4:59 AM Page 398 CHAPTER 5 Stresses in Beams (Basic Topics) Solution 5.5-9 NUMERICAL DATA 9k FC Mmax I BC MAX. BENDING STRESS AT B 16 ft F C (BC) 1 (8) (22)3 12 * [22 Mmax 144 k-ft 1 (8 12 smax 0.625) 3 2 (0.875)] I smax 3 Mmax (12) a 22 b 2 I ; 9.53 ksi 4 1.995 * 10 in. Problem 5.5-10 A railroad tie (or sleeper) is subjected to two rail loads, each of magnitude P 175 kN, acting as shown in the figure. The reaction q of the ballast is assumed to be uniformly distributed over the length of the tie, which has cross-sectional dimensions b 300 mm and h 250 mm. Calculate the maximum bending stress smax in the tie due to the loads P, assuming the distance L 1500 mm and the overhang length a 500 mm. P a P b a L h q Solution 5.5-10 Railroad tie (or sleeper) P 175 kN L 1500 mm q DATA 2P L + 2a b 300 mm a S h 250 mm M1 500 mm bh2 6 3.125 * 10 Substitute numerical values: 3 m3 Mmax 17,500 N # m 21,875 N # m M2 21,875 N # m MAXIMUM BENDING STRESS BENDING-MOMENT DIAGRAM smax Mmax 5 21,875 N # m 3.125 * 10 3 m3 7.0 MPa (Tension on top; compression on bottom) M1 qa2 2 M2 2 qL a + ab 22 Pa2 L + 2a PL 2 2 L P a + ab L + 2a 2 P (2a 4 L) PL 2 ; ...
View Full Document

Ask a homework question - tutors are online