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Over 2000 buildings were surveyed by members of the Colegio de Ingenieros (CICM) and Sociedad Mexicana de Ingenieria Estructural (SMIE) in Mexico City following the Puebla-Morelos Earthquake of 2017. This inventory of surveyed buildings included nearly 40 collapses and over 600 buildings deemed to have structural damage. Correlation of damage with peak ground acceleration (PGA), peak ground velocity (PGV), predominant spectral period, building location, and building properties including height, estimated stiffness, and presence of walls or retrofits was investigated for the surveyed buildings. The evidence available suggests that (1) ground motion intensity (PGV) drove the occurrence of damage and (2) buildings with more infill and stiff retrofit systems did better than other buildings.

A method is presented for extracting empirical capacity curves from building earthquake response data. The method can be applied to buildings with acceleration response records from each floor to develop story empirical capacity curves assuming the building has flexible columns and rigid floors. The method can also be applied to buildings with acceleration response records from the roof and ground to develop a fundamental mode empirical capacity curve. The method relies on extracting the restoring force and relative displacement of the system by removing damping force, considered as equivalent viscous damping, from the inertial response, using a proposed viscous damping identification procedure. The method is demonstrated using data from a small-scale, three-story experimental model subjected to strong base motion.

Following the 12 January 2010 Haiti earthquake, teams of students and faculty members from the United States and Haiti surveyed 170 reinforced concrete (RC) buildings in Port-au-Prince and Léogâne. This paper summarizes the survey results and compares them with results from a similar survey done after the 1999 earthquakes near Düzce, Turkey. The survey results demonstrate that the frequency of damage in RC buildings was higher in Haiti than in Turkey. This increased level of damage is consistent with practical screening criteria based on cross-sectional areas of building columns and walls. Based on these criteria, 90% of the structures surveyed in Haiti would have been classified as seismically vulnerable before the earthquake. Damage was more frequent in structures with captive columns. A two-tiered screening process is suggested to rapidly assess the vulnerability of scores of poorly built low-rise RC buildings in future earthquakes.

Several school buildings were surveyed in the disaster areas of the Marmara (17 August 1999, [Formula: see text]), Düzce (12 November 1999, [Formula: see text]), and Bingöl (1 May 2003, [Formula: see text]) earthquakes in Turkey. Among them, 21 reinforced concrete buildings were found to have an identical floor plan. Lateral load resisting structural system consisted of reinforced concrete frames (moment-resisting frame) in 16 of the buildings and structural concrete walls integrated with the moment-resisting frame (dual system) in the remaining five buildings. The number of stories above ground in these buildings ranged from two to four. These school buildings provide a nearly ideal test of the effect of a single important structural characteristic on the performance of buildings with structural designs that are uniform in all other respects. Our observation is that the presence of structural walls improves the behavior of reinforced concrete systems drastically.

There is no convincing evidence indicating that future ground motion in at least two-thirds of Istanbul, Turkey, shall be less demanding than the ground motions that devastated the city of Duzce, Turkey, in 1999. Comparison of vulnerability indices calibrated for Turkish construction indicates that the structures of the buildings in Istanbul are no better than the structures of buildings in Duzce. On the basis of these arguments, we project that a future earthquake near Istanbul may cause severe damage or collapse approximately quarter of a million buildings. Leaving the vulnerable buildings as they are and organizing for emergency response is not an option for Istanbul. DOI: 10.1193/1.2424988