2001 ASD Supplements - unprotected PDF - American Wood Council

GL-30CAPACITY SELECTION TABLES5.1 GeneralCapacity and stiffness values for structural glued laminatedtimber are provided in this section. The capacityvalue is based on a normal load duration (10 years). Forother load durations, the tabulated capacities should bemultiplied by the appropriate load duration factor (seeSection 4.2).5.2 Bending Capacity, M, and Shear Capacity, VBending capacity, M, and shear capacity, V, are givenfor various allowable stress levels in Table 5.1 for Westernspecies glued laminated timber and Table 5.2 forSouthern Pine glued laminated timber. These capacitiesshall be further multiplied by applicable design adjustmentfactors given in Section 4 of this Supplement. Notethat the tabulated values for bending capacity, M, haveNOT been adjusted for volume factor (see Section 4.9of this Supplement) as the length of the glued laminatedtimber member is not specified in the tables.The bending capacities in Tables 5.1 and 5.2 are basedon fully laterally supported members. When members arenot laterally supported, see the NDS for design details.As noted in Section 3.2, tabulated horizontal shearvalues have been arbitrarily reduced by 10% to allow forin-service checking. The designer may increase the tabulatedshear capacity values by 10% if allowance forchecking is not a design concern.5.3 Bending Stiffness, EITables 5.3 (Western species) and 5.4 (Southern Pine)provides the bending stiffness for various glued laminatedtimber sizes at different E levels. The EI values may beused for deflection computations.5.4 Tension Parallel to Grain Capacity, TTension parallel to grain capacity, T, can be calculatedby multiplying the tensile strength parallel to grain(given in Tables 3.1 and 3.2) by the cross sectional area(given in Tables 9.1 and 9.2). This capacity shall be furthermultiplied by applicable design adjustment factorsgiven in Section 4 of this Supplement.5.5 Compression Parallel to Grain Capacity, PCapacity for compression parallel-to-grain, P, (crushing)can be calculated by multiplying the allowablecompressive stress parallel to grain (given in Tables 3.1and 3.2) by the cross sectional area (given in Tables 9.1and 9.2). This capacity shall be further multiplied by applicabledesign adjustment factors, especially the columnstability factor when appropriate, given in Section 4 ofthis Supplement.APA – The Engineered Wood Association