Dear Sir(s)
I am doing a Elevated Tank design in Staad. Now Indian IS 1893 Part II (seismic code) does give details on how to calculate the impulsive and convective (non inertia part of upper volume of water stored). So I can manually calculate Base Shear and Moments and add to the other forces at foundation level and do the foundation analysis.
But, I want to take the Staad help. But how to figure out lumping of water mass and how to connect it to main structure as modelling does not have any node or vertical member inside the elevated tank. An if I can create a member, what will be its rigidity.
Even if I go for a Impulsive mode and lump the whole water mass at the centroid of the circular water tank, how could I transfer the horizontal force at base. Moreover the slab of tank is made in plates with no nodes.
Enclosed is the staad model.
Please, please help. I am stuck.
Regards
Rajarshi
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