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TR.32.2 Member Load Specification

This set of commands may be used to specify member loads on frame members

General Format

member-list { { UNI | UMOM } dir-spec f1 f2 f3 f4| { CON | CMOM } dir-spec f5 f6 f4| LIN dir-spec f7 f8 f9 | TRAP dir-spec f10 f11 f12 f13 }


dir-spec = { X | Y | Z | GX | GY | GZ | PX | PY | PZ }
  • X, Y, & Z specify the direction of the load in the local (member) x, y and z-axes.
  • GX, GY, & GZ specify the direction of the load in the global X, Y, and Z-axes.
  • PX, PY, & PZ may be used if the load is to be along the projected length of the member in the corresponding global direction.
Note: Load start and end distances are measured along the member length and not the projected length.
f1 value of uniformly distributed load (UNI) or moment (UMOM).
f2, f3 distance of from the start of the member to the start of the load, and distance from the start of the member to the end of the load, respectively. The load is assumed to cover the full member length if f2 and f3 are omitted.
Note: Uniformly distributed moments can not be assigned to tapered members for analysis.
f4 Perpendicular distance from the member shear center to the local plane of loading. The value is positive in the general direction of the parallel (or close to parallel) local axis. If global or projected load is selected, then the local Y component of load is offset the f4 distance; the local Z component is offset the f4 distance; and the local X component is not offset.
Note: The local x component of force is not offset (i.e., no secondary moment is caused by axial load).
f5 value of concentrated force (CON) or moment (CMOM)
f6 distance of from the start of the member to concentrated force or moment. f6 will default to half the member length if omitted.
f7, f8 LIN specifies a linearly decreasing or increasing, or a triangular load. If the load is linearly increasing or decreasing then f7 is the value at the start of the member and f8 is the value at the end.
f9 If the load is triangular, then f7 and f8 are input as zero and f9 is the value of the load in the middle of the member.
f10, f11 The starting and ending load value for a trapezoidal linearly varying load (TRAP), respectively. The TRAP load may act over the full or partial length of a member and in a local, global or projected direction.
f12, f13 the loading starting point and stopping point, respectively. Both are measured from the start of the member. If f12 and f13 are not given, the load is assumed to cover the full member length.


  1. In earlier versions of STAAD, the LINear type of member load could be applied only along the local axis of the member. It has been modified to allow for global and projected axes directions also.
  2. If the member being loaded has offset distances (see MEMBER OFFSET specification), the location of the load is measured not from the coordinates of the starting node but from the offset distance.
  3. Trapezoidal loads are converted into a uniform load and 8 or more concentrated loads.
  4. A UNIT command may be on lines in between member-list lines.
  5. If a load location is less than zero, it is reset to 0.0.
  6. If a load location is greater than the length, it is reset to the length.


619 CON GY -2.35 5.827
68 TO 72 UNI GX -0.088 3.17 10.0
186 TRAP GY -0.24 -0.35 0.0 7.96
3212 LIN X -5.431 -3.335
41016 UNI PZ -0.075
3724 LIN GY -6.2 -7.8