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

5.6 Structural Plywood - Design ProceduresLimit State Design to AS 1720.1-1997The design capacity of structural plywood designed in accordance with the limit states design format of AS1720.1–1997, is achieved by modifying the characteristic strength capacities by a material capacity factorΦ, a geometric section property, and in-service factors (k, j and g factors). Structural capacity factorreliability is achieved through the use of these modified characteristic strength capacities and factored loadsas detailed in AS/NZS 1170.1 - 1997.Strength Limit State CapacityThe strength limit state condition is satisfied when the design capacity of the structural plywoodexceeds the design load effects from the factored loads. That is:g 19).Φ R > S*where Φ R = design capacity of the plywood memberS* = design action effect, eg. bending moment, M*, shear force, V*, etc.and Φ R = Φ k mod [f o '.X]where Φ = capacity factork mod = product of relevant modification factors(eg. k 1 , k 6 , k 7 , k 12 , k 19 ,fo'= appropriate characteristic strengthX = geometric section property.Serviceability Limit States CapacityThe serviceability limit states are achieved when in-service displacements and vibrations are keptwithin acceptable limits. Calculated bending deflections and shear deformations must be modified by inservice modification factors (j 2 , j 6 , and g 19 , as appropriate). Guidance on serviceability limit states aregiven in Appendix B of AS 1720.1-1997.5.7 Strength & Stiffness limit states design capacities5.7.1 Loading Normal to the Plane of the Plywood PanelFIGURE 5.3 Shows Loading Normal to the Plane of the Plywood Panel.FIGURE 5.3: Notation for bearing and shear normal to the face of the plywood panel and for flatwise bendingplywood26