From O86 8.4.3.1, the factored flatwise bending moment resistance is
Mr = f Krb FbSeff
where
f = 0.9.
Fb is the factored bending resistance in the longitudinal layers for major-axis design and for the transverse layers for minor-axis design. The unfactored fb is given in Table 8.2 and it is factored by the load duration factor and possibly a fire-retardant factor.
Krb is 0.85 for major-axis design and 1.0 for minor-axis design
Seff = 2 (EI)eff / E h
where
h is the panel depth for major axis loading, and the panel depth minus the thickness of the outermost layers for minor axis design.
E is the modulus of elasticity from Table 8.1 for the longitudinal layers when loading is along the major strength axis, and for the transverse layers when loading is along the minor axis
