Seismic rehabilitation of concrete buildings after the 1985 and 2017 earthquakes in Mexico City

The 19 September 2017 Puebla-Morelos earthquake provides a unique opportunity to (a) study the effectiveness of seismic rehabilitation methods implemented in Mexico City after 1985 and (b) collect large amounts of data on current building rehabilitation practices. This article presents and discusses seismic rehabilitation efforts conducted on concrete buildings after the 1985 and 2017 earthquakes. Building damage and vulnerabilities, code provisions for rehabilitation, and common repair and retrofit techniques used in these two periods of time are summarized. The performance of four buildings rehabilitated after 1985 is examined based on results from field investigations conducted after the 2017 event. These rehabilitations were effective in improving the performance of these buildings according to observed damages and estimated shaking intensities. To allow a more systematic assessment of seismic rehabilitations in future earthquakes, an inventory of rehabilitated buildings in Mexico City is currently under development. Preliminary data obtained from this inventory effort are presented and discussed.