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En este trabajo se describen los efectos producidos por algunos sismos importantes en construcciones de la ciudad de Morelia, Michoacán, la morfología urbana, las características de los suelos, las fallas sísmicas locales, así como la evolución de parámetros de diseño sísmico que se han propuesto en los reglamentos de diseño locales. Se señala la importancia de la Red Sísmica Nicolaita, compuesta de diez estaciones acelerométricas, en la obtención de registros que permitan mitigar el riesgo sísmico y con los cuales ha sido posible establecer diferencias apreciables del movimiento de los suelos en la ciudad y que deben ser consideradas en estudios de peligro. También, se presentan algunos acelerogramas registrados y espectros de respuesta. El objetivo de este trabajo es mostrar que, de acuerdo con la historia sísmica y los daños producidos por eventos sísmicos pasados, la ciudad de Morelia es un sitio propenso a sismos destructivos, lo que vuelve fundamental contar con una red de monitoreo.

In this paper, the seismic behavior of the main nave and cloister of the Guadalupe Church and San Diego Convent is studied, a structure dating from the 18th century and built in the historic center of the city of Morelia, Mexico, considering a set of 9 real seismic acceleration records of September 19 2017 earthquake obtained at seismic stations located near the epicenter but at almost 100 kilometers from this building, which were used first without any scale factor and then a scale factor was applied to reach the expected maximum peak accelerations of the ground at the site for probabilistic return periods of 475 years and 975 years.

Large earthquakes have epicenters on the Pacific Coast of Mexico and many of them are responsible of damages in reinforced concrete (RC) bridges. The Pacific Coast is a highly active seismic zone where most of the strong earthquakes in the country occur. In this region, there are new and old RC bridges subjected to ground motions from interplate and intraplate seismic sources. This study evaluates the seismic vulnerability of ten RC bridges, with typical geometry in Mexico, and two existing bridges located close to the Pacific Coast of Mexico. The group of ten bridges includes two span lengths (20 and 40 m), two pier heights (6 and 10 m) and two substructure types (single and multi-colum piers). The bridges were designed according to the regulation codes used in practice in Mexico, and their seismic capacity (C) was evaluated with pushover analysis. The seismic demand (D) was determined using a group of more than one hundred seismic records from interplate and intraplate seismic sources. The random ratio C/D was used to assess the fragility curves of the bridges using four earthquake return periods. The results showed that the two existing bridges have similar trend of behavior and the fragility curves of the bridge models can predict the expected behavior of multi-column or single-column existing bridges.