Study on Partial Collapse of a Five Story Reinforced Concrete Building during the 2010 Chile Earthquake

Abstract

After the 2010 Chile earthquake about 20 reinforced concrete (RC) buildings were declared inhabitable and four buildings faced demolition order within the city of Santiago, which is located more than 300 km away from the epicenter. The objective of this paper is to present the main findings of, and the lessons learned from, apreliminary study on the partial collapse of a 5-story residential building. To achieve this goal, the seismic design of this building was verified using the response spectrum method following the Chilean seismic design code at the time of the earthquake. The building was designed with a mixed RC and confined masonry structure; however the parking level was structured mostly with RC in order to maximize parking spaces. It is concluded that: (1) walls at the basement level had inadequate demand/capacity ratios, (2) confinement requirements in RC walls needs to be revised, and (3) vertical irregularity must be incorporated in Chilean code.