Answer:
1) 1.4(D + F)
2) 1.2(D + F + T) + 1.6(L + H) + 0.5(Lr or S or R)
3) 1.2D + 1.6(Lr or S or R) + ((0.5 or 1.0)*L or 0.8W)
4) 1.2D + 1.6W + (0.5 or 1.0)*L + 0.5(Lr or S or R)
5) 1.2D + 1.0E + (0.5 or 1.0)*L + 0.2S
6) 0.9D + 1.6W + 1.6H
7) 0.9D + 1.0E + 1.6H
Explanation:
Load and Resistance Factor Design
there are 7 basic load combination of LRFD that is
1) 1.4(D + F)
2) 1.2(D + F + T) + 1.6(L + H) + 0.5(Lr or S or R)
3) 1.2D + 1.6(Lr or S or R) + ((0.5 or 1.0)*L or 0.8W)
4) 1.2D + 1.6W + (0.5 or 1.0)*L + 0.5(Lr or S or R)
5) 1.2D + 1.0E + (0.5 or 1.0)*L + 0.2S
6) 0.9D + 1.6W + 1.6H
7) 0.9D + 1.0E + 1.6H
and
here load factor for L given ( * ) mean it is permitted = 0.5 for occupancies when live load is less than or equal to 100 psf
here
D is dead load and L is live load
E is earth quake load and S is snow load
W is wind load and R is rain load
Lr is roof live load
