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1.4.3-Loads Included
SIZER includes dead, live, snow, wind, live roof, live storage, impact, and earthquake loads as load types, and allows you to specify that the either the live loads, live roof loads, or both are construction loads.
Impact loads are considered a live load by ASCE 7 and are not mentioned in 1.4.3, but load combinations are generated with impact loads considered as a separate load type because these combinations have a different load duration factor and a shear reduction factor for glulam members.
Live roof loads are not mentioned in 1.4.3 but are required by ASD load combinations in ASCE 7 2.4.1. These are loads due to things like rooftop gardens, parking, and assembly areas.
Live storage loads are not mentioned in 1.4.3 or defined in ASCE 7, but are included because they have a different LRFD time-effect factor than other live loads and are treated as permanent loads in deflection calculations.
NDS Commentary C2.3.2 indicates that it is conventional practice to consider a construction load as a roof live load for which the 1.25 load duration factor applies, so it is necessary to allow both construction roof live loads and occupancy live loads on the structure at the same time.
Sizer therefore has a check box "All roof live loads are construction loads" which allows roof live loads to be treated as construction loads even when live loads on other parts of the structure are not.
1.4.4-Load Combinations
For Beam, Column and Concept modes Sizer generates a comprehensive set of load combinations that reflect those recommended by the IBC and ASCE 7 building code authorities, for both ASD and LRFD design. Refer to Load Combinations
See also: Pattern loads