Basic Strength of Materials Calculation ????
Basic Strength of Materials Calculation ????
(OP)
I am working on a shaft failure and I came across something that puzzles me.
If I look at Mechanical Engineers handbook it lists a formula for maximum stress in center of a beam where the load is applied in the center with supports on the two ends being: WL / 4Z
W: weight
L: over all length
Z: section modulus
However from strength of materials class many moons ago I remember using Mc / I for stress due to bending. What is the difference?
If I look at Mechanical Engineers handbook it lists a formula for maximum stress in center of a beam where the load is applied in the center with supports on the two ends being: WL / 4Z
W: weight
L: over all length
Z: section modulus
However from strength of materials class many moons ago I remember using Mc / I for stress due to bending. What is the difference?





RE: Basic Strength of Materials Calculation ????
Tobalcane
"If you avoid failure, you also avoid success."
RE: Basic Strength of Materials Calculation ????
The section modulus is defined as Z = I/c
Also, (for a beam of length L, simply supported on each end with a load, W, applied at the center) the maximum moment is
M = WL/4 (at dist = L/2)
If we insert these into your standard Mc/I equation, this leads to the equation,
WL/4Z
The difference is that this equation is specific for this loading configuration and Mc/I still holds for *any* bending loading configuration.
RE: Basic Strength of Materials Calculation ????
Heckler
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RE: Basic Strength of Materials Calculation ????
RE: Basic Strength of Materials Calculation ????