# How to determine factor of safety in a beam (lap joint)?

A beam is made up by bolting together two cold-drawn bars of AISI 1018 Steel as a lap joint. The bolts used are ISO 5.8. Ignoring any twisting how do I determine factor of safety in this connection?

I have placed an image of this problem under the following to view the question:

http://img73.imageshack.us/img73/6568/pr...

this looks like an official question, but there appears to be information left out.

Depending on what level of a question this is, the answers will be different. (kinda like in math, in 2nd grade we were taught there were no "negative" numbers)

The edge distance from the bolt center to the edge of the plate is left out. This is a critical dimension. The problems appears to suggest other factors you are being asked to ignore.

To figure this out, the two moments about the bolts create a "couple", are you this far in engineering yet?

if you are not, the simple answer is the single shear bolt diameter value, times the distance from center. The value of the steel plates/thickness gives you the moment arm capacity.
The force given/distance gives you the required value
actual/theoretical gives you the safety factor.

as in this type of engineering solutions, edge distance is very critical, note some of the well publicized failures due to the lack of this calculation.