Understanding Extreme Geohazards: The Science of the Disaster Risk Management Cycle European Science Foundation Conference November 28 to December 1, 2011, Sant Feliu de Guixols, Spain

The economic impact of seismic retrofit on heritage buildings with historic reinforced concrete skeleton structure of the interwar time

Maria Bostenaru Dan
"Ion Mincu" University of Architecture and Urbanism, Bucharest, Romania, maria.bostenaru@iaim.ro

Groups of actors (conservators, engineers, inhabitants, investors) put different priorities in interventions on heritage buildings. In seismically vulnerable buildings interventions can be done at different levels, from avoiding collapse up to assuring immediate post-earthquake functionality. Between these two poles there are degrees of damage depending on the performance aim set. The costs of the retrofit and post-earthquake repair differ depending on the targeted performance.

Not only an earthquake has impact on a heritage building, but also the retrofit measure, for example on its appearance or its functional layout. A solution must be found on how much change we accept for retrofit and how much repairable damage we take into account. There are two impact studies.

Numerical simulation was run for interwar buildings for several earthquakes, and for successive earthquakes, considering also the case when retrofit is done between two earthquakes. A developed system counted building elements according to their degree of damage. Device computations for the retrofit and for the repair measures were done considering the material prices and the labor hour prices, a flexible mean, being able to be applied for different countries, also ones where there is no database on existing projects in seismic retrofit. Diagrams and tables have been built to see how the total costs vary as addition between the preventive retrofit and the postearthquake repair, compared to the costs of rebuilding.