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Plate Loads tab

Used to apply loads to elements.

Tip: To apply nodal loads on plate nodes, whether they are corner nodes or not, select the Region Node Load tab under the Nodal Load tab in this dialog.

Pressure on Full Plate

Used to define a pressure load that acts on the full surface of an element. (To define a pressure load that acts on a small part of an element, see the Partial Plate Pressure tab that is described in the coming pages).

SettingDescription
Load W1 is the pressure magnitude, in the current units.
Direction

The load may be applied along:

  • the local X, Y, or Z axis,
    Tip: Loads in the Local X or Local Y directions can be used to represent in-plane friction loads.
  • one of the global X, Y or Z axes (GX, GY, or GZ)
  • projected area of the plate (PX, PY, or PZ)

Concentrated Load

Use this option to define a concentrated load that acts at a specific point within the boundary of an element. If a load acts at a node point of an element, it is advisable to apply it using the Nodal Load option described in earlier pages.

SettingDescription
Load Force is the magnitude of the load.
Direction The load may be applied along the local Z axis, or along one of the global X, Y or Z axes (GX, GY, GZ).

Partial Plate Pressure Load

Used to specify a uniform pressure load on the entire element or on a user specified portion of the element.

SettingDescription
Load The element pressure (force per unit area) or concentrated load (force unit). For concentrated load, the values of X2 and Y2 must be omitted, while X1 and Y1 must be specified.
X1, Y1, X2, Y2 For element pressure (force per unit area), these values represent the coordinates of the rectangular boundary on which the pressure is applied. If X1, Y1, X2, and Y2 are all zero,the pressure is applied over the entire element. If X1 and Y1 are specified but X2 and Y2 are omitted, then W1 is treated as a concentrated load.
Direction GX, GY, and GZ represent the global X, Y, and Z directions along which the pressure may be applied. Local Z indicates that the pressure is applied normal to the element in the local Z direction.
Note: For more information, please refer to TR.32.3 Element Load Specifications .

Trapezoidal

Used to specify a trapezoidally varying pressure load on a plate. The load is applied over the entire element in the local Z direction, varying along the positive local X or Y direction. 

SettingDescription
Direction of Pressure GX, GY, and GZ represent the global X, Y, and Z directions along which the pressure may be applied. Local Z indicates that the pressure is applied normal to the element in the local Z direction.
Variation along element

Define the direction in which the pressure varies as either the local X or Y direction or choose the joint option which is discussed next.

The Joint option is used to apply different values of pressure at different nodes of the plate element. When checked, the dialog updates to allow a different pressure value for each of the four plate corner nodes.

Hydrostatic

Used to model loads due to hydrostatic pressure on one or more adjacent elements. The Hydrostatic load is converted to Trapezoidal loads on the elements. The load is applied over the entire area of the element.

SettingDescription
Force Enter value of the load at the minimum and maximum global axis in current units.  For example, to model a retaining wall with soil pressure, W1 is the force at the bottom of the wall and W2 is the force at the top of the wall.
Interpolate along Global Axis Specify the global axis (X, Y, or Z) along which the load should vary from W1 to W2.  For example, the load would vary along the Y axis on a vertical retaining wall.
Direction of pressure Specify the direction of design pressure as Local Z axis or global axes (GX, GY or GZ) and click on Add. This will assign the linearly varying hydrostatic load on all the selected elements.
Select Plate(s) Opens a Selected Item(s) dialog, which is used to generate a list of selected plates. The Create Load Items dialog is dismissed until all loads are added using the Plates Cursor tool in the View Window. Once Done is clicked, the Create Load Items dialog re-opens with the Plate table populated. Unlike other load definition options, we must select plates for this option to become active.