how can I analyze acomposite flitch plate beam, 20 ft. long, 3/8 steel plate by 9 in. sandwiched between 2 - 2x12,bolted with 3/8" carriage bolts on 12" centers? By hand, no software. Need it this week.
In addition, shear flow between the different materials must be calculated. If the steel plate is not dead center of the 2x12's and the 3/8" bolts also are not at the center, number of bolts have to be calc'd to justify that the load can be shared based on the stiffnesses of each pieces.
There is a two-page article in the September 1989 issue of Civil Engineering magazine on Flitch Beam Design. The article is by J. D. Wiesenfeld, who was (is?) a professor at the New York Institute of Technology's School of Architecture.
Thanks guys! Really preciate the help on the flitch plate beam. This was a garage door lintel that the building inspector turned down. I was asked to look at and make it work.
My first time. It's the best thing that has happened for Engineers.
As stated before you may design plate to take full bending. Space bolts to provide lateral support to steel plate. Also, if considering both wood and steel, bolts must be sized and spaced to transfer load to wood side plates...Good luck.