i want to apply the load combination of (1.2D + 1.0W + L + 0.5(Lr or S or R)) however , I don't have snow nor rain loads and the live loads at roof are the same as other lower floors taken as ( 2 KN / M2 )
so what would be my comb in this case or it is not applicable to my analysis?
the case would be applicable .
you will have Lr = 2kN . m 2 and L = 2 kN . m2
in combnination your roof live ( Lr ) will become 0.5 in roof , while the floor live load (L) will become one .
note roof live load is of different nature when compared to Floor live as Roof live load is usually not always permanent or in other words not occupied . for steel building , if it is inaccesible roof , the roof live load in only present if any maintainence activity is present .
Alex Immanuel Thainese
please see the definition of Lr in the attached code page ( Lr= roof live load of 1kn /m2 or less ) and how this agrees with your explanation above