Repair of an 18-Story Shear Wall Building Damaged in the 2010 Chile Earthquake

Three transverse shear walls at one corner of an 18-story building in Santiago failed in flexural compression just below grade, causing the ground floor to drop 75 mm and the corner of the roof to displace laterally 185 mm. Cracking of walls and floor slabs caused significant building distortions. Nonlinear analyses of shear walls and floor slabs were used to understand the measured residual displacements and determine effective stiffnesses needed for a three-dimensional (3-D) model of the building. This model was used to estimate jacking forces needed to reposition the building. Existing cracks in shear walls were injected with epoxy, and fiber reinforced plastic (FRP) fabric was used to control new cracks. Instrumentation was used during jacking to monitor building movements, inclinations of walls and slabs, maximum compression and tension strains in walls, and crack widths. The building was repaired for less than 25% of the replacement cost and with much less impact on building habitants and the surrounding community.