In situations where the centroid of the slab is not at a uniform elevation, the in-plane and out-of-plane stiffnesses of RAM Concept 's slab elements will interact. For example, in a T-beam, the axial stiffness of the web and the flanges will interact with their bending stiffnesses (creating a stiffer section than just the web and flange bending stiffnesses added together).

In these situations, you may need to modify the in-plane behavior to modify the out-of-plane behavior. For example, if you want to reduce a T-beam bending stiffness by half, you would need to set both KMs and KFr to 0.5.