Issue link: http://alpine.uberflip.com/i/684939
A girder is a truss that supports other framing members such as; roof trusses, floor trusses, conventional framing, or a combination of framing. Let's now take a look at calculating the supported PLF load applied to a girder's bottom chord and the resulting girder reactions. Remember that for this example the supported trusses are non-girder trusses. Building on what you have learned, we will use the reaction from the previous example to calculate the PLF to be applied to the girder bottom chord. As you'll recall, the reaction = 400 pounds. We could apply 200 PLF to the bottom chord of the girder. However, this load would be conservative compared to the load calculated by iDesign. We calculated the load based on ½ of the supported span. This applies the entire load to the girder's bottom chord. However, some of that load is distributed to the girder's top chord. When we add the full load from ½ of the supported truss plus the full 2' of PLF to the top chord, the result is more load than what is actually there.