Title: The 1999 Tehuacan (mw = 7.0) and Oaxaca (Mw = 7.5) Mexican Earthquakes: Lessons Learned

Author(s): S.M. Alcocer, C. Reyes, D. Bitran, O. Lopez-Batiz, R. Duran-Hernandez, and L. Flores

Publication: Symposium Paper

Volume: 209

Issue:

Appears on pages(s): 65-88

Keywords: columsn; earthquake engineering; historical buildings; hospitals; housing; masonry; reinforced concrete; repair; schools; strengthening

DOI: 10.14359/12495

Date: 9/26/2002

Abstract:
On June 15, 1999, a magnitude Mw = 7.0 earthquake occurred with epicenter located southwest from the city of Tehuacan, Puebla, and on September 30, 1999, a Mw = 7.5 magnitude earthquake occurred with epicenter located northeast from the city of Puerto Escondido, Oaxaca, Mexico. The earthquakes affected a wide geographical area, including seven states. Few casualties were recorded. In Puebla, 15 percent in the State of Oaxaca and only the remaining ten percent in the States of Morelos, Mexico, Tlaxcala, Veracruz and Guerrero; the second earthquake only affected the State of Oaxaca. Historical buildings, dwellings, hospitals, schools and roads were mostly impacted. Some damages were also experienced in bridges and lifelines. The economic activities were not severely impaired. This paper summarizes the seismological characteristics of the event, its economic impact and the Emergency measures adopted by the authorities. Observation made during several visits to the affected regions of Puebla and Oaxaca on the behavior of soils and foundations, lifeline, schools, dwellings, historical monuments and commercial buildings are described. Recommendations for the development o fvulnerability reduction programs are presented.