Assessing and Mitigating Seismic Risk for a Hospital Structure in Zaruma, Ecuador: A Structural and Regulatory Evaluation

Abstract

This research, conducted in Zaruma, southern Ecuador, seeks to evaluate the seismic vulnerability and performance level of the Humberto Molina Hospital's reinforced concrete buildings. The study employs an examination of national and international seismic codes for rehabilitation, along with the implementation of recommended techniques. Structural characteristics of the buildings were identified through auscultation, surveys of reinforcing steel, and the extraction of concrete cores. The amassed data, coupled with a seismic hazard analysis of the site, facilitated a structural assessment of the blocks, conducted in accordance with national (MIDUVI) and international (ASCE/SEI) codes. The Federal Emergency Management Agency (FEMA) subsequently proposed rehabilitation alternatives for each block. Due to the importance of the hospital's functions, data collection was limited to blocks B3 and B4. The structural system, composed of moment-resisting concrete frames, exhibits potential vulnerabilities due to knocking (collision) and torsion, attributed to its irregular form. Structural evaluation revealed that block B4 adheres to the drift limits stipulated by the ASCE 41-13 standard (below 2%), while block B3 exceeds these limits (2.05-2.80%). Recommended rehabilitation strategies for B3 encompass mass reduction (removal of the second floor, representing a dead load of 700kg/m 2 and a live load of 200kg/m 2 ), and the introduction of additional rigidity and strength (extension of structural elements). For block B4, it is suggested that each sub-block be made independent. These interventions aim to facilitate the hospital's reopening, thereby benefiting the Zaruma Mining District community.