To obtain the vertical loading on a slab element which is modeled using a fairly fine mesh, users may implement a joint pattern through the following process:

For each loading patch, or set of patches which act together, select Define > Joint Pattern to define a joint pattern, as shown in Figure 1:

Tutorials > Joint-pattern first steps > Define_pattern_names_form.png

Figure 1 - Name joint patterns

Select joints which are contained within the patch or patches. Next, select Assign > Joint Pattern, then assign a dimensionless scale factor D, such as 1.0. This process is shown in Figure 2:

Tutorials > Joint-pattern first steps > Pattern_data_form.png

Figure 2 - Pattern data

Select the slab elements, then select Assign > Area Loads > Surface Pressure to assign pressure (force/area) such that it acts downward on the top face, according to the appropriate load pattern. This menu is shown in Figure 3:

Tutorials > Joint-pattern first steps > Area_surface_pressure_load.png

Figure 3 - Area surface pressure load

The pressure on each element will be interpolated from the product between joint-pattern values and the pressure assigned, which is 5.0 kN/m in this example. If only one element joint has a nonzero pressure, a quarter of the load will be applied. Load pressure is multiplied by element tributary area such that users need not manually calculate nodal forces.

Display joint pattern

To graphically display the joint-pattern assignment, select Display > Show Misc Assigns > Joints.

Select Display > Show Load Assign > Area Surface Pressure Values to display the area load assigned to each joint.