In the RAM Steel Beam Design module, criteria used in the design of composite beams with Bison plank can be specified. This is done with the Criteria – Bison PC Units command. In this dialog box there are three sections: Gap Data, Transverse Reinforcement and Precast Units. Only the Gap Data may be specified by the user; the other two sections are for informational purposes only, indicating values that the program will assume and use.

The Gap is the distance between the ends of the precast units. It affects the effective width of compression area of concrete and the stud capacity. It is a function of the beam flange width, the required width of bearing of the precast unit on the steel beam, the construction tolerance of the precast units and the construction and erection tolerance of the structural steel. Generally, the Bearing Width is 40mm, the Slab Tolerance is 20mm and the Construction Tolerance is 15mm.