Technologies for Retrofitting existing buildings and structures to make them earthquake resistant

8. Case Studies
8.1 General 8.2 Masonry Building 8.2.1 The Building 8.2.2 Seismic Evaluation 8.2.3 Retrofitting of Building 8.3 RC Buildings 8.3.1 RC Building-1 8.3.2 RC Building-2

Appendix-I: Performance Levels
Appendix-II: Checklist for Visual Inspection Masonry Buildings
Appendix-III: Checklist for Visual Insection of RC Buildings
Appendix-IV: Stiffness Matrix of a 3D Beam Element
Appendix-V: Checklist for Visual Inspection of Earthquake Damaged Buildings

Summary : Even though, the Codes of Practice on Earthquake Resistant Design of Buildings and Structures is in existence since 1962, the construction of number of unsafe building are growing in the county due to its non compliance specially in private sector of housing construction. Only recently, the code provisions on Earthquake Resistant Design are made mandatory in few States and its implementation is yet to take full momentum. As a result, existing earthquake unsafe buildings are growing to an alarming proportion.

Any major earthquake in future will repeat the scenario of Killari 1993 and Bhuj 2001 when thousand of lives were lost and a staggering number of houses were collapsed/damaged. To upgrade the existing buildings seismic retrofitting has to be undertaken in order to make these unsafe houses to resist future earthquakes.

Any government action is just not feasible and therefore individual house owner/builder has to undertake the retrofitting measures. An effort has been made here to present the simple techniques of retrofitting the existing load bearing masonry buildings and reinforced concrete framed buildings. However these techniques can also be applied to other structures as well. This deals with seismic evaluation of existing buildings, mathematical modeling for analysis of buildings, materials for retrofitting, retrofitting of non-engineered, engineered and earthquake damaged buildings, and two case studies.

Much literature on retrofitting of building is already available including the Bureau of Indian Standards (BIS). It is felt that a common builder may not easily understand these. Therefore a need has been felt to provide adequate information about seismic retrofitting which can be easily understood and implemented. A complete chapter has been devoted to retrofit design of masonry and RC buildings. Two case studies on seismic retrofitting of a load bearing building and a reinforced concrete framed building have also been included. It is hoped that this will provide adequate information required for effective implementation of seismic retrofitting.