EWPAA Structural Plywood and LVL Design Manual - Engineered ...

where:Δ = Δi +h33j14xh35Q *Qkpfor loads perp’ to grain (13.21)∆ = deformation (mm) of a single bolt in a Type 1 jointj 14 = duration of load factor for bolted joints;h33= stiffness factorh35 = 1.5 for first (3) joints of FIGURE 13.8.= 2.5 for multiple member connections, the fourthjoint in FIGURE 13.8.∆ i = initial displacement of joint due to oversize holesNcon= total number of bolts in the connectionQ* = serviceability load effect (N) parallel orperpendicular to the grain for a single boltQ kl = characteristic strength of bolt parallel to grain (N)Qkp= characteristic strength of bolt perpendicular tograin (N)13.17 Bolted Connection - Design ExampleThe connections in a roof truss provide the opportunity to expose a number of importantfactors regarding bolted joint design. Therefore, in this example the heel joint of a truss will bedesigned.A roof truss having the geometry shown in Figure 13.11 is to be featured in a commercialbuilding to be constructed on Queensland’s Gold Coast. The truss has been designed, butLVL with A faces for appearance, is being considered as an alternative. The joints of the trussare to be bolted using M12 galvanised bolts. The design load is to be taken as the load in thetop chord.The critical load combination for the strength limit state is to be:nominal dead load : Gnominal live load : Q= 8kN (axial compression top chord)= 6kN (duration of load 5 days) axial compression top chordThe LVL for the single top chord is 150 x 45mm and for the double bottom chard 150 x 35mm.The joint strength group of the LVL is JD3.209