Friday

August 29, 2014

August 29, 2014

Posted by **Jon** on Wednesday, December 7, 2011 at 8:03am.

- Statics -
**drwls**, Wednesday, December 7, 2011 at 8:18amWhat are Fb and Fv? Is one of them the rupture or yield stress?

What factor of safety do you wish to use?

- Statics -
**Jon**, Wednesday, December 7, 2011 at 8:24amFb=allowable bending stress and Fv=unit shearing stress , I just need to find the minimum diameter allowable to meet those conditions

- Statics -
**drwls**, Wednesday, December 7, 2011 at 8:42amThat allowable shearing stress of 100 psi seems suspiciously low. There is usually a certain plane where the shearing stress is about half the tensile stress, so everything would fail in shear if the strength were that low.

Look up or calculate the location and value of the maximum bending moment, M.

For uniform loading at w weight/length, the maximum bending moment is

M = w L^2/8

I recommend using w = 33.33 lb/inch, with L in inches, if you are going to compute stresses in psi.

The maximum shear occurs at the ends, and is

V = w L/2

The maximum shear stress is

Fshear = V/(pi D^2/4)

The maximum bending stress is

Ftensile = M c/I

where c = D/2 and I = pi*D^4/64

- Statics (P.S.) -
**drwls**, Wednesday, December 7, 2011 at 8:53amref: Eshbach: Handbook of Engineering Fundamentals. College Edition, 1952.

What a great book! Mine cost me $6.40 in about 1957.

It was a pleasure to consult it again.

I am sure you will find the same formulas in many strength of materials texts and handbooks.

**Related Questions**

statics - A cantilever beam member made from steel with hollow circular cross ...

statics and strengths - A cantilever beam member made from steel with hollow ...

strength of mechanics - Determine the midspan value of EI(shear stress) for the ...

Physics - HW8_1: CANTILEVERED BEAM WITH TAPERED SQUARE CROSS SECTION A ...

Physics/Mechanics - HW8_1: CANTILEVERED BEAM WITH TAPERED SQUARE CROSS SECTION A...

Physics - HW8_1: CANTILEVERED BEAM WITH TAPERED SQUARE CROSS SECTION A ...

MAT LAB - HW8_1: CANTILEVERED BEAM WITH TAPERED SQUARE CROSS SECTION A ...

MIT 2.01X - HW8_1: CANTILEVERED BEAM WITH TAPERED SQUARE CROSS SECTION A ...

math - Use this rule to find the number of feet of lumber in a log:"Take 4 ...

Equilibrium - A beam having a length of 20 metres is pivoted at its mid point. A...