09-26-2009, 09:30 AM
(02-02-2009, 06:37 AM)aslam Wrote: hello, Juice, Yasir,
Plz correct (guide) me if i am wrong :
(1) Two way slabs shall be modelled as SHELL and need meshing
core: There are two kinds of analysis, Global and local analysis. If you are using shell in the global analysis "be very careful, specially is your bldg's period is to the limit. It would increase the stiffness of your bldg. And it might not match your detailing.
(2) One way slabs shall be modelled as MEMBRANE and NO need meshing
[color]core[/color]: Etabs default for membrane is automatic. Thats why you thought messing is not required. Check column reactions of your model to be sure loads are properly captured. A good way of checking is to export one flr and check in etabs if col loads are same as manual calcs.
(3) Stiffnes modifiers for beams,columns,walls,slabs needed on when nonlinear
analysis not performed.
core: modifiers should be provided, special for crack condition. UBC and other codes specifics this. There are no full 100% I value in reality.
(4) ETABS only gives area of reinforcement for columns & beams (section to be
designed & not to be checked) and not the dia of bars and its arrangement.
Core: all can be check and design be etabs, except slab and slating walls.
(5) for beam we get steel requirement at column face, mid span only and not at
other sections of beam. How to decide upto which distance extra top steel at
support and extra stirrups at end required?
Regards