TR.32.1 Joint Load Specification
General Format
JOINT LOAD
joint-list (inclined-spec) *{ FX f8 | FY f9 | FZ f10 | MX f11 | MY f12 | MZ f13 }
Where:
inclined-spec = INCLINED { f1 f2 f3 | REF f4 f5 f6 | REFJT f7 }
Use the optional inclined-spec to specify a joint load in a inclined load axis. See Inclined Load Axis System below for details.
Parameter | Definition |
---|---|
f1, f2, f3 | x, y, z relative distances from the joint in the global directions to the reference point |
f4, f5, f6 | x, y, z global coordinates of an arbitrary reference point |
f7 | a joint number whose x, y, z global coordinates are the reference point |
f8, f9, f10 | force values in the corresponding global direction (even at inclined support joints). |
f11, f12, f13 | moment values in the corresponding global direction. |
Example
UNIT FEET KIP
*…
JOINT LOAD
3 TO 7 9 11 FY -17.2 MZ 180.0
5 8 FX 15.1
UNIT INCH KIP
12 MX 180.0 FZ 6.3
Notes
- Joint numbers may be repeated where loads are meant to be additive in the joint.
- A
UNIT
command may be on lines in between joint-list lines. - If moments are for dynamic mass, then the units are assumed to be force-length2.
- An
INCLINED REF
orINCLINED REFJT
must be included on the same line as the preceding joint list. No continuation sign (-
) may be used with this command.
Inclined Load Axis System
If the joint loading is specified using the option
INCLINED
, then the axes in which the direct forces
(and about which for moment forces) are applied are realigned from the global
directions of X, Y, and Z to the directions x', y', and z' as shown below.
The reference point –whether it is specified using absolute coordinates, relative distances, or a reference joint– defines the direction of the x' axes from the loaded node to the reference point. The direction of the Y' axes is then defined as the direction perpendicular to x' that lies in the plane of X' and Y. In the special case of when X' is in the direction of Y, Y' is taken to be the direction of Z. The direction of Z' is then defined as the direction perpendicular to the plane X' and Y' and follows the right-hand rule as for all other axes systems used in STAAD.Pro.
Example
JOINT LOAD
4 INCLINED 1.0 -1.0 0.0 FX 10
JOINT LOAD
3 INCLINED REFJT 7 FZ -30