Per your picture you show the bolt passing through both plates fully. If either or both are threaded then you must account for that. However, by the nature of threaded parts, as long as your threads are drilled and tapped properly it will be simple shear.
Calculate your shear length as the circumference of the hole radius minus 1.5 mm for the distance between the bolt and the threaded hole. The shear area is then that length times the thickness of your threaded plate. Multiply that by 0.6 times the yield strength of your plate (13th AISC equation J4-3) and divide by your safety factor (1.5 if using AISC ASD). This is the capacity of the threaded part, you'll need to check the bolt capacity but, assuming your plate is A36 steel, it will likely not control the design. There may likely be other requirements such as deformation of threads that must be checked but this will give you the most basic capacity of the part.
Maine EIT, Civil/Structural. Going to take the 1st part of the 16-hour SE test in October, wish me luck!
