05-03ChapGere.0014 - 334 A-PDF Stresses in Beams (Basic...

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

View Full Document Right Arrow Icon
Problem 5.8-10 A simply supported wood beam of rectangular cross section and span length 1.2 m carries a concentrated load P at midspan in addition to its own weight (see figure). The cross section has width 140 mm and height 240 mm. The weight density of the wood is 5.4 kN/m 3 . Calculate the maximum permissible value of the load P if (a) the allowable bending stress is 8.5 MPa, and (b) the allowable shear stress is 0.8 MPa. Solution 5.8-10 Simply supported wood beam 334 CHAPTER 5 Stresses in Beams (Basic Topics) Maximum bending moment occurs under the concentrated load. 5 18,680 lb-ft 5 224,200 lb-in. F ROM A PPENDIX F: Select 8 3 10 in. beam (nominal dimensions) A 5 71.25 in. 2 S 5 112.8 in. 3 s 5 M S Ê S req 5 M max s allow 5 224,200 lb-in. 2500 psi 5 89.7 in. 3 t max 5 3 V 2 A Ê A req 5 3 V max 2 t allow 5 3(6407 lb) 2(150 psi) 5 64.1 in. 2 5 (6407 lb)(3 ft) 2 1 2 (120 lb / ft)(3 ft) 2 M max 5 R B d 2 qd 2 2 (b) C ONSIDERING THE WEIGHT OF THE BEAM q BEAM 5 17.3 lb/ft (weight density 5 35 lb/ft 3 ) V max 5 6485 lb 8 3 10 beam is still satisfactory for shear.
Background image of page 1
This is the end of the preview. Sign up to access the rest of the document.

This note was uploaded on 09/20/2009 for the course COE 3001 taught by Professor Armanios during the Spring '08 term at Georgia Institute of Technology.

Ask a homework question - tutors are online