Apr 7, 2009 #1 NS4U Structural Apr 2, 2007 320 Can someone give me a reference why the SJI says to reduce the moment of inertia by 1.15 when calcing deflection of steel trusses? Thanks
Can someone give me a reference why the SJI says to reduce the moment of inertia by 1.15 when calcing deflection of steel trusses? Thanks
Apr 8, 2009 #2 WillisV Structural Apr 24, 2005 1,352 The factor is used to account for the affect of the axial deformations in the webs and for joint eccentricity. A discussion and an alternate means of this calculation can be found here: http://www.steeltools.org/assets/0/544/546/670/3a1d42e3-3cc5-4486-a0c3-3019e87259e3.pdf Upvote 0 Downvote
The factor is used to account for the affect of the axial deformations in the webs and for joint eccentricity. A discussion and an alternate means of this calculation can be found here: http://www.steeltools.org/assets/0/544/546/670/3a1d42e3-3cc5-4486-a0c3-3019e87259e3.pdf
Apr 8, 2009 #3 Lion06 Structural Nov 17, 2006 4,238 I believe it is because a joist isn't really a "beam", so to speak, and the traditional deflection formula (5wl4/(384EI)) won't capture the difference in behavior. Upvote 0 Downvote
I believe it is because a joist isn't really a "beam", so to speak, and the traditional deflection formula (5wl4/(384EI)) won't capture the difference in behavior.
