Load Combinations
| Setting | Description |
|---|---|
| Steel Standard Provision Mode | Eight Steel Design Codes are available in the Standard Provision mode of the RAM Frame program: AISC 360-05 ASD, AISC 360-05 LRFD, AISC ASD 9th, AISC LRFD 3rd, Eurocode, CAN/CSA-S16-95, BS 5950-1990, BS 5950-2000 and AS 4100-98. Depending on the currently selected steel code, load combinations can be generated based on different building codes. The load combination dialogs for each of the steel codes are described in the following links. |
| Steel Seismic Provisions | The load combinations generated and created in this mode are only used where the selected code requires that the 'Special Seismic Load Combinations' be applied. For AISC 1997 the term 'Special Seismic Load Combinations’ refers to load combinations 4-1 and 4-2, for UBC 1997 LRFD this refers to load combinations 3-7 and 3-8, while for UBC 1997 ASD this refers to load combinations described in section 2213.5.1. Refer to the relevant codes for appropriate Omega values. The omega value is dependant on the building system used. For models with more than one building system (with different Omega values), the code check may need to be performed more than once. The different omega values would then be specified depending on the system being checked. It is important to note that a large portion of the checks performed in the Seismic Provision mode use the load combinations defined in the Steel-Standard Provision Mode. The engineer should ensure that the currently selected standard provision load combinations (generated and custom) are appropriate for the checks to be performed in the Seismic Provision mode. |
In the Load Combination Generation dialog box, a list of analyzed load cases appears in the Analyzed Load Cases to Include list box. These are the load cases that are available to be used for code generated load combinations. Click on the Apply button when the appropriate load cases have been selected (Use column selected) and the load combinations will be generated and displayed in the lower spreadsheet. Select the Use column for all load combinations to be considered in the design.
In addition to the program generated load combinations, the user can define their own combinations. User defined load combinations as created in the dialog obtained from the Combinations-Custom command.