Bracing Wood Truss
Bracing Wood Truss
(OP)
Does anyone have any guidelines for designing and analyzing wood trusses with scab and/or t-bracing?
I have a project that requires me to analyze and reinforce existing trusses that will be beneath an overbuilt roof. The trusses’ are severely inadequate with 15' long 2x4 web members without any lateral bracing. Much of the truss system can be braced with continuous lateral bracing however some locations will require scab bracing or t-bracing.
My approach was to consider only the bracing's affect upon the members stiffness by calculating the stiffness ratio as le/(r*sqrt(12)) (Appendix H.4 of NDS). I then used the stiffness ratio to calculate my allowable compressive stress which was compared to the axial load over the area of the original 2x4. Is this method acceptable?
I have a project that requires me to analyze and reinforce existing trusses that will be beneath an overbuilt roof. The trusses’ are severely inadequate with 15' long 2x4 web members without any lateral bracing. Much of the truss system can be braced with continuous lateral bracing however some locations will require scab bracing or t-bracing.
My approach was to consider only the bracing's affect upon the members stiffness by calculating the stiffness ratio as le/(r*sqrt(12)) (Appendix H.4 of NDS). I then used the stiffness ratio to calculate my allowable compressive stress which was compared to the axial load over the area of the original 2x4. Is this method acceptable?





RE: Bracing Wood Truss
Shrestha, D., D. A. Bender, and F. E. Woeste. 2003. T-Brace design for MPC wood truss webs.Forest Products Journal 53(1): 61-66.
Anderson, C.A., F.E. Woeste and D. Bender. 2002. Wood Bits: Checking T-brace capacity onwood truss webs. Building Standards 71(6): 5-10.
RE: Bracing Wood Truss
http://www.sbcindustry.com/structuremagazine.php?PHPSESSID=806nifrsfp5r60m7b09d79hag1