question 1: [21 points] Two steel plates are attached to each other using N similar bolts.
This system is supposed to carry 100 Klb with safety factor of at least 2 guarding against sep-
aration of the plates. Here is the known properties of each bolt and the two plates.
Washers: We use washers at the top and bottom of the two plates. Washers are steel with
thickness of 0.095 in and E=30 Mpsi.
Nut: The height of the nut is 0.4375 in.
$\frac{1}{2}$in- 13UNC Grade 8 steel. E=30 Mpsi. Proof strength is 120 kpsi.
Bolt: The Bolt is
Plates: Each plate's thickness is 2 in and made up of Al. E=10.3 Mpsi, the ultimate strength
is 47 kpsi, and the yield strength is 25 kpsi.
1.1) Find the minimum length of the bolt with zero threads out of the nut.
1.2) How many nuts do we need for this structure with safety factor of at least 2 guarding
against separation of the plates?
1.3) What is the safety factor guarding against separation of the plates for your design (for
your suggested N)?
The plates are Al, not steel. Use the give E in the problem statement.
the attachment is permanent.
