How to calculate strength of welds (welded joints)?

[fpdlskf]

I need to calculate strengths of welds / welded joints.

Could you point me to a handbook or website?

I will be a bit more specific. The welds are fusion welding w/o any filler materials

and the materials to be welded are thin strips of stainless steel (thickness 5/1000 in)

 

[Chronos]

http://www.dtic.mil/dtic/tr/fulltext/u2/401387.pdf