Post-Earthquake Structural Evaluation, San Isidro Office Building

2007 | Lima PERU

Client Bloomberg LP
Structural Engineer Expert Guy Nordenson and Associates

Following the 15 August 2007 Peru earthquake, GNA was hired by the Bloomberg LP to inspect a 15-story reinforced concrete building in the San Isidro district of Lima, Peru.  The inspection, which was conducted three days after the earthquake, included review of the below-grade parking structure and eight of the above-grade levels to which access was provided.  The inspection included comprehensive documentation of damage, which included hairline cracks in concrete beams and walls, as well as the recording of structural dimensions to confirm that the as-built conditions corresponded to the available structural documents.

Using the existing structural drawings for the building and the Peruvian seismic code, GNA ran a response spectrum analysis on a global structural model of the building to assess the code-compliance of selected beams and columns.  The analysis suggested that the building was designed according to code both in terms of strength and displacements.  GNA also acquired accelerograms from the earthquake at a site in San Isidro and determined that based on the fundamental periods of vibration of the office building in the two primary directions, the actual acceleration experienced by the building during the earthquake was on the order of 30% of that for which the building was designed.  Therefore the code analysis was a conservative representation of the demands imposed on the structural members.