{[ promptMessage ]}

Bookmark it

{[ promptMessage ]}

05-05ChapGere.0004

# 05-05ChapGere.0004 - because the shear flow on the contact...

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

Problem 5.11-6 Two wood box beams (beams A and B ) have the same outside dimensions (200 mm 360 mm) and the same thickness ( t 20 mm) throughout, as shown in the figure on the next page. Both beams are formed by nailing, with each nail having an allowable shear load of 250 N. The beams are designed for a shear force V 3.2 kN. (a) What is the maximum longitudinal spacing s A for the nails in beam A ? (b) What is the maximum longitudinal spacing s B for the nails in beam B ? (c) Which beam is more efficient in resisting the shear force? Solution 5.11-6 Two wood box beams SECTION 5.11 Built-Up Beams 353 z y O z y O 200 mm 360 mm 360 mm t = 20 mm t = 20 mm A 200 mm B Cross-sectional dimensions are the same. All dimensions in millimeters. b 200 b 1 200 2(20) 160 h 360 h 1 360 2(20) 320 t 20 F allowable load per nail 250 N V shear force 3.2 kN s longitudinal spacing of the nails f shear flow between one flange and both webs s max 2 FI VQ f 2 F s VQ I I 1 12 ( bh 3 b 1 h 1 3 ) 340.69 10 6 mm 4 (a) B EAM A 680 10 3 mm 3 78.3 mm (b) B EAM B 544 10 3 mm 3 97.9 mm
This is the end of the preview. Sign up to access the rest of the document.

Unformatted text preview: because the shear flow on the contact surfaces is smaller and therefore fewer nails are needed. s B 5 2 FI VQ 5 (2)(250 N)(340.7 3 10 6 mm 4 ) (3.2 kN)(544 3 10 3 mm 3 ) Q 5 A f d f 5 ( b 2 2 t )( t ) ¢ h 2 t 2 ≤ 5 (160)(20) 1 2 (340) s A 5 2 FI VQ 5 (2)(250 N)(340.7 3 10 6 mm 4 ) (3.2 kN)(680 3 10 3 mm 3 ) Q 5 A p d p 5 ( bt ) ¢ h 2 t 2 ≤ 5 (200)(20) ¢ 1 2 ≤ (340) Problem 5.11-7 A hollow wood beam with plywood webs has the cross-sectional dimensions shown in the figure. The plywood is attached to the flanges by means of small nails. Each nail has an allowable load in shear of 30 lb. Find the maximum allowable spacing s of the nails at cross sections where the shear force V is equal to (a) 200 lb and (b) 300 lb. z y O 3 in. — in. 3 16 — in. 3 16 8 in. in. 3 4 in. 3 4 A-PDF Split DEMO : Purchase from www.A-PDF.com to remove the watermark...
View Full Document

{[ snackBarMessage ]}

### What students are saying

• As a current student on this bumpy collegiate pathway, I stumbled upon Course Hero, where I can find study resources for nearly all my courses, get online help from tutors 24/7, and even share my old projects, papers, and lecture notes with other students.

Kiran Temple University Fox School of Business ‘17, Course Hero Intern

• I cannot even describe how much Course Hero helped me this summer. It’s truly become something I can always rely on and help me. In the end, I was not only able to survive summer classes, but I was able to thrive thanks to Course Hero.

Dana University of Pennsylvania ‘17, Course Hero Intern

• The ability to access any university’s resources through Course Hero proved invaluable in my case. I was behind on Tulane coursework and actually used UCLA’s materials to help me move forward and get everything together on time.

Jill Tulane University ‘16, Course Hero Intern