U.S.-Japan Cooperative Program: Displacement Amplification Factors for the Seismic Evaluation and Retrofit of Existing RC Frames

University Of Wisconsin-Madison, Madison WI

Investigators

Abstract

Many existing buildings designed according to older code provisions have performed poorly in recent strong earthquakes (e.g., 1994 Northridge, U.S., 1995 Hyogo-Ken Nanbu, Japan). The damage caused by these events reached unprecedented figures which resulted in some of the costliest natural hazard events in recent history. Since damage and lateral deformations are interrelated, the control of lateral displacement during an earthquake is key to providing for damage control. The main objectives of this investigation are: a) to quantify the influence of the degrading characteristics of older buildings on the lateral displacements and b) to develop approximate expressions to compute displacement amplification factors. These objectives will be accomplished by computing the lateral displacement of a variety of older systems subjected to a large database of earthquake records. Statistical and regression analysis of the data will be conducted to develop simplified expressions for the calculation of displacement amplification factors. The project will be conducted in close collaboration with investigation at Nagoya Institute of Technology in Japan. The results of this investigation will provide new and needed data that will allow researchers and practicing engineers to make better decisions in their evaluation and rehabilitation procedures in both the U.S. and in Japan