Load Combinations

If you haven’t used the Auto Generation of Load Cases option above, you can manually define the load factor for each of the load groups that you wish to include in the particular loading case, having already set up the load groups and load case titles, in the Loading Cases tab.

When a new file is created, MasterFrame will always generate a number of default loading cases and associated loading combinations.  The MasterFrame standard defaults include Dead plus Live (Ultimate) and Live Only (Serviceability) cases or 5 Composite Design load cases if any part of your frame has been set as a composite floor.

To define a load factor for a load group in the current loading combination:

1.Select the appropriate loading case using the drop down list or spin button. At this stage the load case has already been added using the Loading Cases tab. See above.

2.Select the load group you wish to define. For example, if you wish to include the D1 loading group, then select the Dead category and load set 1 (as shown).

3.Assign a load factor to the selected load group by typing in a value or clicking on one of the common load factors displayed. Once a non-zero load factor is given to a load group, it should appear the main blue coloured load combination cell.

To remove a load group from the load combination:

1.Select the load group you wish to remove by simply clicking on the load group item in the blue load combination window.

2.Assign a zero value to its load factor. This can also be done by typing in a zero or selecting it from the common load factors.

All the load factors defined in the current Loading Combinations are multiplied by the Global Factor (Usually set to 1), which is independent for each loading case. The Global Factor enables you to investigate structures under incremental loading, for example 90% of the loads (just change the Global Load Factor to 0.90).

The Wind Options are only applicable when using the integrated MasterKey Wind Analysis program for the calculation and application of the wind loading – see Wind Loading section of manual.

These loading combinations of factored load groups are subsequently used in the analysis.

If you need to edit a particular group load factor in several load combinations at once, use the Edit Load Group > Add/Remove load groups in multiple cases  ‘Edit’ button. This will open up a list of the load case combinations.

1.Highlight the load cases in which you want to change the load factor. You can highlight multiple cases using the keyboard Ctrl button and click on the cases in question.

2.In the Settings choose whether to add or remove the load factor.

3.Select the Load Group from the drop list.

4.Change the load factor – a zero will omit the load factor from that group.

5.Click on the ‘Apply’ button to implement the changes.