Design action or design load (W*) is the combination of the nominal actions or loads imposed upon the structure (e.g., transverse loads on a beam) multiplied by the appropriate load factors as specified in AS/NZS 1170 (Structural design factors).
Design action effects (S*) are the actions (e.g., design bending moments, shear forces, axial loads) calculated from the design actions or design loads using an acceptable method of analysis.
Limit states design requires structural memebers and connections to be proportioned so that the design action effects (S*), resulting from the design action (W*), is less than ot equal to the design capacity (#Rn).
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