Evolution of Seismic Zoning in India Over Various Revisions of IS 1893

Zoning of India from Earthquake point of view is a very important aspect of Earthquake Resistant Design of Structures. At first instance the seismic zone in which the structure is located gives an idea of severity of an earthquake. The seismic zoning of India has been changing from the IS Code IS 1893 from one version to the other. This has been mainly due to more and more data of earthquakes became available as time passed. Moreover, more and more research in the area of Earthquake Engineering has made the change of zoning imperative. In this paper an effort has been made to critically review the changes in zoning in various versions of the code.