HOW TO DO MANUAL CHECK AGAINST STAAD RESULTS FOR SEISMIC FORCES?

Example
The structure is 36x21m and is symmetrical in x and Z direction as well as in vertical elevation and its total height from the footing is 74m.(21 storey)

The building is in Zone III and the time period as per IS 1893-2002(PartI) for infill is taken 0.09h/√d.

After analysis through STAADPRO the followings check is carried out to verify and check the results between manual calculation and the software results.




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A. TIME PERIOD:

As per IS CODE 1893-2002(Part I) T =0.09h/ √d where d is the direction along the EQ forces.
Tx =0.09x74/ √36 =1.11 Sec.
Tz =0.09h/ √21 =1.453 Sec.

The output of STAADPRO is

TIME PERIOD FOR X 1893 LOADING = 1.11000 SEC
TIME PERIOD FOR Z 1893 LOADING = 1.45333 SEC
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