Monitoring of a rehabilitated building in soft soil in Mexico and structural response to the September 2017 earthquakes; Part 1, Structural health monitoring system

The seismic response of an instrumented 22-story rehabilitated building is presented. The building analyzed is as part of a complex (called CCUT) with three low-rise structures and a common basement founded on soft soil that was built in 1964. Since it was under construction until date, the building tower has experienced differential settlements and tilting. To mitigate such problems, the building has been subjected to several rehabilitations over the years. During the 1985 and 2017 high-intensity earthquakes in Mexico City, the tower suffered some damage. The aim of this article is to discuss the structural health monitoring system implemented for the tower and to describe the structure's performance since the last rehabilitation in 2009. A monitoring methodology designed and implemented as a structural warning system based on five structural health indicators, two on seismic severity and three on structural performance, to automatically process seismic records, is presented. The results of the seismic response of the CCUT tower between 2011 and 2018 indicate that the structure had suffered moderate damage. Analysis of data, corroborated by building inspection, confirmed that the structure exhibited good performance during the 19 September 2017 Puebla-Morelos earthquake. The importance of the information obtained from the structural warning system is highlighted as a promissory tool for establishing a robust decision framework for occupants' safety.