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Homework Statement
Homework Equations
M = Fd
σ/y = M/I
T/J = τ/r
σalternating (σa) = σmax  σmin / 2
σmean (σm) = σmax + σmin / 2
soderberg: σa/σ'e + σm/σy = 1/FoS
The Attempt at a Solution
I am still unsure whether my progress so far is correct but..
I have calculated J to be 38.35e9 m^{4} and I to be 19.17e9 m^{4}. I then use these values in the shear stress and normal stress equations to find that:
σ = 82.16 MPa
τ = 41.07 MPa
I apply these values to a loading element diagram (am I right in thinking there is no force in the y direction??) and then used Mohrs circle to find that the maximum and minimum principal stresses are:
σmax = 99.17 MPa
σmin = 17.01 MPa
When applying these values to the σalternating and σmean equations, I am not sure whether it is expressed as:
σa = σmax  σmin / 2
σa = 99.17  (17.01) / 2 OR
σa = 99.17  17.01 / 2
After I get the correct σa and σm values and I need to find a suitable factor of safety, I'll have σa, σm, σy but im not sure how im to find the σ'e, or is there a different method to finding a suitable factor of safety?
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