Design a bolt for 40 kN double shear joint with steel and aluminum

[dilipdboss]

1. Homework Statement
A tensile load of 40KN is applied on a double shear joint. Design a bolt that holds the members safely without any kind of failure. A UTS 1250 class steel [allowable stress = 1080 MPa, Ultimate strength = 1250 MPa] bolt is used and the members (lugs) are made of AA2014 alloy [allowable stress=380 MPa, Ultimate strength = 420 MPa].

2. Homework Equations
shear failure: sigmaS = P/(2*A)
tensile failure: sigmaT = P/2*(w-d)
bearing failure: sigmaBR = P/(d*t)


thanx for the help.

 

[pongo38]

One way of doing a 'design' like this is to try something. Try, say diameter = 20 mm and see what loads it can carry in double shear and bearing. decide which of these is critical. Compare that with the requirements of the question, and adjust accordingly.