STRUCTURAL ENGINEERING FORUM OF INDIA [SEFI]

hemalmistry · ... Joined: 01 Jul 2009 Posts: 70

According to cl. 7.3.10, stability co-eff (thita) is given as Pu*delta/H. I think it should be Pu*delta/Hu*hi as per Annex E of IS 456_2000. Similar equation is there in ASCE 7. Stability index (co-eff) shall be less than 0.2 to avoid instability.

However, p-delta analysis is compulsary for all cases as per cl. 7.3.9. According to ASCE 7 p-delta analysis is required only when stability co-eff is greater than 0.1 (may be 0.04 as per indian code). According to IS 456_2000, columns are non sway column when stability index is less than 0.04.