The result of defining a point support is a single support at a finite element node. The result of defining a line support is one or more line supports that are each located at a finite element edges. RAM Concept uses the thickness of the lowest numbered element in determining the support elevation. For this reason, it is not advisable to locate point supports or line supports at slab steps.

All supports that have a horizontal rigidity should be placed at the mid-depth of the slab or they may cause an unintended arch action in addition to their horizontal rigidity (mid-depth placement is done by setting the "Elevation above slab soffit" to be one-half of the slab depth).

Normally there is no need to use horizontal fixities in point and line supports, as RAM Concept automatically stabilizes the structure in the x- and y-directions (you can turn this automatic stabilization off in the General tab of the Calc Options dialog box). One situation where you might use a horizontal support is a structure braced against sidesway but modeled without bracing members (perhaps something other than a concrete wall provides the bracing).

Be very careful about specifying anything but "Fixed in z-direction" for point supports and "Translation in z-direction fixed" for line supports. For point supports, fixing the point support in the r- or s-direction could result in arch / membrane action. For line supports, fixing the slab translation along or across the support could result in arch / membrane action.