05-10-2014, 08:23 AM
Seismic Retrofit of Elevated Steel Water Tanks
Author: N. S. Potty*, Universiti Teknologi Malaysia, MALAYSIA S. Nambissan, Advanced Defence Laboratory, Bangalore, INDIA | Size: 189 MB | Format: PDF | Quality: Unspecified | Publisher: ICCBT 2008 - C - (09) – pp99-108 | Year: 2008 | pages: 10
The Indian Standard “Criteria for Earthquake Resistant Design of Structures: IS 1893-1984” has been revised. Areas in earthquake zone 1 have been merged to earthquake zone 2 and Killari is now in earthquake zone 3. The seismic zone factors have been also changed. Response spectra are now specified for 3 types of founding soil strata and a response reduction factor has been introduced. Elevated water tanks are vulnerable to earthquake, owing to large mass concentrated at the top of a relatively slender supporting structure. Existing elevated steel water tanks in India designed using IS 1893-1984 is checked for safety as per revised code (IS 1893-2002) by carrying out static and forced dynamic analysis. It is observed that the structure is unsafe due to under-estimation of seismic load as per old code provisions. Retrofit measures such as additional structural elements and passive devices like viscous and friction dampers are modelled and structure analysed again to check for compliance with the revised code. Conclusions drawn from this study are presented.
Code:
***************************************
Content of this section is hidden, You must be registered and activate your account to see this content. See this link to read how you can remove this limitation:
http://forum.civilea.com/thread-27464.html
***************************************