RISA News

RISA NewsRISA News

RISA News provides information about upcoming education opportunities, program information/updates and technical solutions for commonly asked questions. Click the title of each individual entry for more information.


August 31, 2010

How Are Wind Loads Generated for Sloped Roofs?

RISAFloor is capable of automatically generating the wind loads on sloped roofs. Let’s look at an example of this with the model below:

Note that all of the roof members are defined as lateral. This is optional, as only the ridge beams truly need to be defined as lateral. However, by defining the rafters as lateral they will transfer into RISA-3D, and will be designed for wind load and uplift, which is a bonus. When transferring the model to RISA-3D make sure that the Generate Roof Wind Loads box is checked in the wind loads dialog.

Once in RISA-3D  you can review the four basic load cases that have been generated by the program (WLX+R, WLX-R, WLZ+R, WLZ-R). A positive and negative load case is created for each wind direction, as the windward load magnitude is different from the leeward. Be sure to generate reversible load combinations for these roof wind loads to account for this in the Load Combination Generator.

Tags: , ,

This entry was posted by RISA News on Tuesday, August 31st, 2010 at 9:00 am and is filed under Technical Solutions. You can follow any responses to this entry through the RSS 2.0 feed. You can leave a response, or trackback from your own site.
Share |

Leave a Reply