Emin for unbraced glulam column design

Question: Per the 2005 NDS^®, which E_min should be used for the design of an unbraced structural glued laminated timber column under purely axial load. Since E_min is now used in the calculation for C_P and there is no E_{axial min} in the NDS Supplement for glulam, which E_min should be used - E_{x min} or E_{y min}?


Answer: Check both the weak axis and the strong axis and use the corresponding E_min for each axis. E_axial is the longitudinal modulus of elasticity and is used only for calculations involving the change in longitudinal dimension of the member. For axial buckling calculations, E_{x min} or E_{y min} should be used as appropriate.