Torsional elastic modulus
Torsional elastic modulus
(OP)
Could anyone give me the fomula for finding the torsional elastic modulus of a rectangular bar. Thanks
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RE: Torsional elastic modulus
J=k*b*t^3
where:
b = width of section
t = thickness of section
k = constant depending on b/t ratio, as follows:
b/t k
1 0.141
1.2 0.166
1.5 0.196
2 0.229
2.5 0.249
3 0.263
4 0.281
5 0.291
infinity 0.333
RE: Torsional elastic modulus
prex
motori@xcalcs.com
http://www.xcalcs.com
Online tools for structural design
RE: Torsional elastic modulus
RE: Torsional elastic modulus
Anthony Tugwell
Project Director & Consulting Engineer  just relocated to Australia
RE: Torsional elastic modulus
The exact text extract is "The value of torsional elastic modulus (G) may be taken as 28.3 GPa for glass fins"
RE: Torsional elastic modulus
The shear modulus is used in computing torsional deformation
(twist) of a member.
G = E / 2 / (1 + mu)
E = young's modulus
mu = Poisson's ratio.
Check any book on structural mechanics for the relationships
between torsional moment, torsional constant, G and twist.
Hariharan
RE: Torsional elastic modulus
Modulus of elasticity, G, also known as Modulus of Rigidity.
G= fV/Y
fv= torsional shearing stress(Pa)
Y= gamma, strain in the material
If u r designing glass than 28.3 GPa is correct, upto 30 is fine.
I would suggest u use the G values directly rather than compute from first principles.
Riz
RE: Torsional elastic modulus
If u use formula given by Hariharan than the parameters are as follows:
E = 70KPa
mu= 0.22
Thus G = 28.7GPa
Riz
RE: Torsional elastic modulus
If u use formula given by Hariharan than the parameters are as follows:
E = 70KPa
mu= 0.22 ( for stress parallel to grain )
Thus G = 28.7GPa
Riz
RE: Torsional elastic modulus
RE: Torsional elastic modulus
Anthony Tugwell
Project Director & Consulting Engineer  just relocated to Australia