RAM Frame uses the effective lengths of beams and columns to calculate the stiffness of these members in the coordinate system at the end of the rigid end zone. These are then transformed to a coordinate system at the joint centerline.
Determination of the rigid end zone depth assumes that the beam's web is parallel to the column flanges or parallel to the column's web.
Normal and Sloping Columns
A reduction factor can be used to scale down the effect of the full rigid end offsets. The Rigid End Zone is then given by:
| REZ = R * Joint Face Distance | |
where
For beams the effective length is calculated as:
| Leff = L - REZi - REZj | (6.12) |
where
|
L
| = | length of member, centerline to centerline |
|
REZi
| = | the Rigid End Zone at end i |
|
REZj
| = | the Rigid End Zone at end j |
For columns, the major axis effective length is calculated as:
| Leff = L - REZXTop - REZXBot | (6.13) |
and the minor axis effective length is calculated as:
| Leff = L - REZYTop - REZYBot | (6.14) |
where
|
L
| = | length of member, centerline to centerline |
|
REZXTop
| = | the Major Axis Rigid End Zone at Top |
|
REZXBot
| = | the Major Axis Rigid End Zone at Bottom |
|
REZYTop
| = | the Minor Axis Rigid End Zone at Top |
|
REZYBot
| = | the Minor Axis Rigid End Zone at Bottom |
