Working with Slab Loads

Working with Slab Loads

Slab Load Properties


"Slab Load Properties" will be loaded when the "Point, Line and Area Loads" option in the "Loading "  ribbon is selected.

A new slab load can be defined by arranging the fields in the properties form and then by clicking the insertion reference.

The following fields exist in this properties form:


Load Type

Depending on the selected load type, necessary definition parameters will be set visible in the properties form.


Load Type

Three Load Type Buttons are available in the upper pane of the properties form to enable the definition of Point Loads, Line Loads and Partial Area Loads.

Slab Load Dimensions (b1, b2)

Horizontal ("b1 ") and vertical ("b2 ") dimensions of the slab load can be defined in these fields.
  1. Point Load: These fields will not be available when point load is selected.
  2. Line Load: "b1" will be the length of line load.
  3. Area Load: "b1" will be the horizontal length and "b2" will be the vertical dimensions of the area load.



Slab Loading Parameters

Slab Load Reference Distances (e1, e2)

Slab loads are inserted based on an axis intersection as reference point. The horizontal distance ("e1 ") and vertical distance ("e2 ") to the lower left corner of the slab load can be defined in these fields. The definition is similar to the definition of “e1” and “e2” in the slab opening section.

Load Angle

The "Angle" field allows you to define rotated slab loads. This is the direction angle of the bottom edge of the area load or direction of the line load measured from global x-axis.

This field will not be available for point loads.

Load Case

For every vertical load case (“G ” and “Q”) a set of load magnitudes can be defined. You can switch load cases using the "Next/Previous Load Case " buttons.

Load Magnitudes

Magnitude of the loads can be defined using the fields provided at the bottom of the properties form.
  1. Point Load: Only one magnitude field will be available for each load case.
  2. Line Load:  Two magnitude fields will be available for each load case, " w1 " for the beginning and " w2 " for the end of the line load. By default, " w2 " will be populated when " w1 " is modified. You can modify " w2 " manually to define a non-uniform distributed loading.
  3. Area Load:  Only one magnitude field will be available for each load case defining the uniform area loading.

Inserting a New Slab Load


To define a new Slab Load:
  1. Press the “Point, Line and Area Loads” button located in the "Loading " ribbon.
  2. Select the Load Type by pressing one of the Load Type Buttons located in the top pane of the properties form.
  3. Enter the loading dimensions ("b1 " and "b2 ") and load position angle ("Angle ", not applicable for point loads) in the "Slab Load Properties" form. Some of these parameters will be invisible depending on the load type selected.
  4. The distances to the reference point ("e1 " and "e2 ") can be defined on the plan or 3D views by picking the reference and insertion points. Instead of picking the insertion point, the relative coordinates of the insertion point can be defined using “F2” keyboard button.
  5. Enter the load magnitudes for each vertical load case that the load will be applied. You can switch load cases using the arrow buttons.
  6. Click the axis intersection which is going to be used as the reference point of the slab hole. Alternatively a direction angle can be defined by clicking an axis intersection and dragging to a second axis intersection point along one of the axes.
Important tip for user when creating slab load to avoid problems or error during analysis. 


Slab load should not be created: 
  1. exactly on edge line of slab
  2. across multiple slabs
  3. clashing with members (ie. wall, column)

Editing an Existing Slab Load


In order to edit an existing Slab Load:

  1. Select an existing slab load.
  2. Modify the fields such as load dimensions or magnitudes in the "Slab Load Properties " form.
  3. Press the "Update " button in the form.
You can repeat this process to as many members as you wish. One loading at a time can be edited by this method.



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