The answer to this question is too complex to describe here. There are too many factors which are not specified in the question, such as load in pounds per linear foot, spacing of the 4X12 joists, as...
first you need to calculate the load on the entire floor. Different uses mean different loads, you look that up in the building code. Then you calculate how much of the floor is held up by the beam....
Yes there is. Good luck trying to obtain one. It is a pretty closely guarded chart. Apparently engineers feel they need to give that information out. At $120 per hour. You might be able to get one in...