PLOAD1

Applied Loads on Bar and Beam Elements

Description: Defines concentrated, uniformly distributed, or linearly distributed applied loads to CBAR and CBEAM elements at user chosen points along the axis.

Format:

Example:

Field Definition Type Default
SID Load set identification number. Integer > 0 Required
EID Element identification number. Integer > 0 Required
TYPE Load type, one of the following character variables: FX, FY, FZ, FXE, FYE, FZE, MX, MY, MZ, MXE, MYE, and MZE. Character Required
SCALE Determines scale factor for X1, X2. Must be one of following character variables: LE, FR, LEPR, or FRPR. Character Required
X1, X2 Distances along element axis from end A. X2 ≥ X1 ≥ 0.0; X2 may be real or blank
P1, P2 Load factors at positions X1, X2. Real or blank

Remarks:

  1. If X2 ≠ X1, a linearly varying distributed load will be applied to the element between positions X1 and X2, having an intensity per unit length of bar equal to P1 at X1 and equal to P2 at X2 except as noted in remarks 7 and 10 below.
  2. If X2 is blank or equal to X1, a concentrated load of value P1 will be applied at position X1.
  3. If P1 = P2 and X2 ≠ X1, a uniform distributed load of intensity per unit length equal to P1 will be applied between positions X1 and X2 except as noted in Remarks 7 and 10 below.
  4. Load TYPE symbols are used as follows to define loads:
    • FX, FY, or FZ: Force in the x, y, or z direction of the basic coordinate system.
    • MX, MY, or MZ: Moment in the x, y, or z direction of the basic coordinate system.
    • FXE, FYE, or FZE: Force in the x, y, or z direction of the element coordinate system.
    • MXE, MYE, or MZE: Moment in the x, y, or z direction of the element coordinate system.
  5. If SCALE = LE (length), the Xi values are actual distances along the bar x-axis, and (if X1 ≠ X2) Pi are load intensities per unit length of the bar.
  6. If SCALE = FR (fractional), the Xi values are ratios of the distance along the axis to the total length, and (if X2 ≠ X1) Pi are load intensities per unit length of the element.
  7. If SCALE = LEPR (length projected), the Xi values are actual distance along the bar x-axis and (if X2 ≠ X1) the distributed load is input in terms of the projected length of the bar.

    Figure 1. PLOAD1 Convention on Bar and Beam Elements

  8. If SCALE = LE, the total load applied to the bar is P1(X2 - X1) in the yb direction.
  9. If SCALE = LEPR, the total load applied to the bar is P1(X2 - X1)COS(α) in the yb direction.
  10. If SCALE = FRPR (fractional projected), the Xi values are ratios of the actual distance to the length of the bar and (X1 ≠ X2) the distributed load is input in terms of the projected length of the bar.
  11. Load sets must be selected in the Case Control Section (LOAD = SID).