Analysis of OWSJ's w/ top chord extension

[PG35]

Does the existance of a top chord extension affect the forces in the web members near the cantilevered end? A simple analysis would suggest that the forces would be greater at the cantilevered end compared to a simply supported case of the same span and loading if there was no top chord extension.

A joist supplier I am working with has designed joists as simply supported and ignored the cantilevered top chord. I find this to be an incorrect analysis.

Can someone comment on the design of joists with top chord extensions?

 

[hokie66]

Yes, if there is a cantilever on one end and not the other, the web forces on the cantilever end will be increased. However, if there is an equal cantilever on both ends, the web forces would not be affected. This assumes symmetrical loading.