General Questions About "sizing" Structural Beams. Hello Guys. I would like to know where I can find high quality info on which types of beams to use for certain applications. Say, for example, a 100 foot span which is supposed to hold 100 tons at the center, or cantilever, and so on. I know there are many factors, such as material strength, "height" of beam, thickness of material, and weight of material, and the like, but I cannot figure out a mathematical relationship even for simple shapes, for I am no savant. For example, is there a way to mathematically deduce how much "torque", or "weight" a ten foot 10"x10" solid square cantilever of 50 KSI steel can handle before permanently deforming? I am assuming these things have been figured out experimentally. Ultimately, I am asking you guys for guidance in terms of recommended sources (internet, and books) for such information, and formulas. Thank you.