Damage Due to the 1985 Mexico Earthquake and the Ground Conditions
Abstract
. This paper presents some types of the damage caused by the Michoacan, Mexico Earthquake of September 19, 1985 and describes the relations between those damage and their ground conditions based on the site investigation in Mexico City and the epicentral zone in January, 1986. The lessons learned from the Mexico Earthquake through the site investigation, are summarized as follows.
Tremendous damage in Mexico City at 400 km distance from the epicenter, was triggered by the amplifications of the ground motions through the soft lacustrine clay deposit which is surrounded by hard volcanic rock formations. At the epicentral zone the damage to structures was relatively small in consideration of the recorded values of the peak acceleration which are 150 to 170 gals because most of structures stand on the firm coastal terrace. Only the City of Lazaro Cardenas, which was developed on the alluvial low ground, were severely attacked by the earthquake. Especially the factories on the reclaimed land were damaged due to the liquefactions. Comparison between the microtremor measurement on La Villita Dam and the FEM analysis suggests that the dam responded to the earthquake as a high dam adding the thickness of the foundation to the height of the dam. In the City of Guzman which is located 200km to the northwest of the epicenter and developed in the basin like Mexico City, most of the houses and pavements were damaged along the small gaps which were considered to relate a fault existing under the ground in the volcanic topography.- Publication:
-
Soils and Foundations
- Pub Date:
- September 1988
- DOI:
- 10.3208/sandf1972.28.3_149
- Bibcode:
- 1988SoFou..28..149O
- Keywords:
-
- dam;
- earthquake damage;
- faults;
- liquefaction;
- measurement;
- settlement;
- site investigation;
- volcanic cohesive soil;
- wave propagation (IGC: B 4/C 9)