Earthquake Damage-Resistant Tall Buildings at Near Fault Regions Using Base Isolation and Rocking Core Walls

This paper studies the computational seismic response of two damage-resistant 20-story tall buildings, located at near-fault regions of strong earthquakes, with a reinforced concrete core-wall to provide the majority of lateral resistance above ground. The first building uses a post-tensioned core-wall designed to rock at the ground level resulting in minimal structural damage in the wall at the maximum considered earthquake (MCE) level of shaking. The second building combines an isolation plane at the base (below ground) of the building with a post-tensioned rocking core wall (dual-isolation system); the dual-isolation system results in minimal structural damage at the MCE level of shaking and reduces significantly demands to non-structural components. The three-dimensional seismic responses of the two buildings are compared to that of a conventionally designed core-wall building designed to develop a flexural plastic hinge in the core-wall. Nonlinear response history analysis is conducted using the two horizontal components of strong historical near fault ground motions. The three building models use a nonlinear beam-truss modeling scheme that explicitly accounts for flexure-shear interaction in RC walls and slabs.