The San Salvador Earthquake of October 10, 1986—Geotechnical Effects

Geotechnical effects generated by the October 10 earthquake were significant. Various types of observed ground failures include landslides, lurching or cracking, and differential fill compaction and settlement. Liquefaction and surface faulting were not observed. Poor compaction was responsible for many ground failures such as differential compaction/densification and settlement of embankment fills and fills placed in former deep barrancas. Foundation failures, if they occurred, were not observable at the time of the reconnaissance because of ongoing rescue and demolition operations and limited accessibility to collapsed buildings and major damaged areas. Preliminary assessment indicates that local geologic and soil conditions appear to have had some influence on the intensity of shaking and damage.