Survey, monitoring and reinforcement of a leaning tower after the 2016 Italy earthquakes. The towers of Palazzo Merli in Ascoli Piceno

The paper illustrates the studies carried out after the 2016 earthquakes to evaluate the stability of the towers belonging to Palazzo Merli in Ascoli Piceno and the reinforcement project that arose from them. The studies were based on different approaches. Advanced techniques for survey and monitoring were used to get a reliable measurement of the real overall geometry of the towers and to check by real-time remote monitoring the possible progression of their tilting. Traditional methods of direct analysis and historical research provided a sound support for the safety assessment, allowing to found the modeling choices on consistent physical data and to assess, experimentally, the resistance of towers to historical earthquakes