A Framework to Evaluate the Benefit of Seismic Upgrading. Issue 2 (May 2019) - Michel, Clotaire
The framework to evaluate the benefit of seismic upgrading ofGalanis et al. (2018) is compared to that present in the Swiss seismic code for existing buildings since 2004, updated in 2017. To illustrate the comparison, the example building ofGalanis et al. (2018) in Zurich is analyzed following the Swiss code. It is shown that the concept of Degree of Seismic Upgrade is not relevant for practical applications. More generally, the approach ofGalanis et al. (2018) would be more suited to a risk-based framework (like the Swiss code) than to a performance-based framework like the one they followed. For existing buildings, we claim that it is appropriate to define the retrofitting strategy based on the absolute level of risk, whereas targeting the safety level of the design code is rarely cost-efficient.