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CSI SAFE has very useful feature to find long term non linear deflection for slabs. The procedure is as follow:
Define Load Cases,
a.Immdeiate Non-Linear(D.L -1 and L.L-1)
b. Sustained Non-Linear(D.L -1 and L.L-0.25)
c. Sustained Non-Linear Long Term (D.L-1 and L.L -0.25)
Define Load Combination for long term deflection as
Immd. NL - Sus. NL + Sus. NL Long term
Then run the analysis and check deflection for the above defined load combination.
the csi safe can run a load case taking in consideration immediate deflection for cracked section ( DL + FLOORING+ LL)
and can also run a load case taking in consideration long term deflection- creep and shrinkage- for cracked section ( DL + 0.25*LL + FLOORING)
to calculate total Long term deflection you can not just add the two cases, as the csi safe in calculating the case of LTD automaticaly add the immediate deflction for (DL+FLOORING+0.25LL) so you will need to subtract the immediate deflection value for (DL+FLOORING+0.25LL) from the immediate deflection load case
it is very simple, after aplying loads and running analysis the program give you deformed shape of structure... now just check left bottom of screen and note the maximum value of deflection or deformation
Using the officaial CSI Safe Guide:
https://wiki.csiamerica.com/display/safe/Cracked-section+analysis
you should make some load cases and soe load combinations as per mentioned in their site.
