WORK IN PROGRESS: RELATIVE SAFETY OF HIGH-RISE AND LOW-RISE BUILDINGS IN LOS ANGELES.

This paper summarizes the first phase of research on the relative safety of buildings in Los Angeles. At this phase, the behaviour of two 20-storey buildings designed according to UBC-1994 provisions and subjected to simulated and recorded/scaled ground motions that represent a rare seismic event is investigated. The seismic event considered in this study is a magnitude 7.15 ground motion initiated in the blind thrust Puente Hills fault system. The effect of beam to column connections detailing on seismic demands is also investigated by developing two models for each building: one with pre-Northridge connection assumptions and the other with post-Northridge ones. In all models, the effects of gravity load carrying system and slab are neglected for simplicity. It is concluded that simulated ground motions representing the magnitude 7.15 earthquake impose higher seismic demands compared with recorded/scaled motions that represent a similar event to the extent that in the high-slip region of the fault, the behaviour of the 20-storey building with post-Northridge connection can be deemed unacceptable. [ABSTRACT FROM AUTHOR]