Seismic Retrofit Using Rocking Walls and Steel Dampers

TLDR

The study introduces key details of a retrofit design for an 11‑story steel reinforced concrete building. The retrofit employs prestressed concrete rocking walls and steel dampers to enhance strength and energy dissipation, and its performance is assessed via extensive nonlinear time‑history analysis of the structure. The rocking system significantly reduces seismic responses and their scattering, making the retrofitted building’s damage mode and performance more predictable and enabling more reliable performance‑based seismic design.

Abstract

A retrofit system of prestressed concrete rocking walls and steel dampers is used to control the seismic damage mode and increase the strength and energy dissipating capacity of an 11 story steel reinforced concrete frame in Japan. Important details of the retrofit design are introduced. The seismic performance of the structure before and after the retrofit is evaluated through extensive nonlinear time history analysis. Results show that the rocking system can significantly reduce both the seismic responses to different earthquake ground motions and their scattering. This makes the damage mode and the seismic performance of the retrofitted building more predictable, leading to a possibility of more reliable performance-based seismic design.