Double ceiling beam
Double ceiling beam
(OP)
Can anyone give me a reference for lateral stability of unbraced ceiling beams? I have two horizontal beams with king posts @ the one third points. I plan on spacing the beams 3 1/2" apart and providing a spacer block sandwiched between the clg beams below the king posts. Spacer block will be bolted thru the clg beams with an all-thread.






RE: Double ceiling beam
For Height:Thickness to assume CL=1.0
2:1 and less case, no supports are required
3:1 or 4:1 case, At ends of members by blocking, bridging, hangers.
5:1 case, then the lateral stability requirements are:
a. The compression edge is held in-line the entire beam length
b. The member ends are held in position with full depth blocking, hangers, or bridging.
Beam Stability Factor Equation:
CL=((1+Q/1.9)-((1+Q/1.9)**2-Q/0.95)**1/2)</= 1.0
G=Fbe/Fb*
Fbe=(Kbe/Ey'/Rb)**2 Kbe= 0.438 Lumber, graded
0.610 Glulamms
Ey'=Ey(Cm)Cl