What are the standard load combinations used in structural design?

Common LRFD load combinations include: 1.4D (dead only), 1.2D + 1.6L + 0.5(Lr or S) (gravity dominant), 1.2D + 1.6(Lr or S) + L, 1.2D + 1.0W + L + 0.5(Lr or S), 1.2D + 1.0E + L + 0.2S, and 0.9D + 1.0W or 0.9D + 1.0E (uplift/overturning). Each combination represents different loading scenarios, and the most critical combination governs design. Factors account for load uncertainty and probability of simultaneous occurrence.