This paper presents a framework for developing aftershock fragility curves for reinforced concrete bridges initially damaged by mainshocks. The presented aftershock fragility is a damage-dependent fragility function, which is conditioned on an initial damage state resulting from mainshocks. The presented framework can capture the cumulative damage of as-built bridges due to mainshock-aftershock sequences as well as the reduced vulnerability of bridges repaired with CFRP pier jackets. To achieve this goal, the numerical model of column jackets is firstly presented and then validated using existing experimental data available in literature. A four-span concrete boxgirder bridge is selected as a case study to examine the application of the presented framework. The aftershock fragility curves are derived using response data from back-to-back nonlinear dynamic analyses under mainshock-aftershock sequences. The aftershock fragility curves for as-built bridge columns are firstly compared with different levels of initial damage state, and then the post-repair effect of FRP pier jacket is examined through the comparison of aftershock fragility curves for as-built and repaired piers.

본 연구에서는 입형펌프의 기초부에 4종류의 여진력이 작용하는 경우의 입형펌프 각 부분에 진동변위, 속도 및 가속도에 대한 시간응답특성을 해석하였으며, 여진형태에 따른 입형펀펌프의 거동을 구명하였고, 진동 해석 프로그램을 개발하였다. 선박용뿐만 아니라 해저광물 채취용 수중펌프 및 육상발전 플랜트 등에 사용되는 각종 입형펌프의 기초여진 문제에 대한 과도응답을 평가함으로서 동적거동을 예지할 수 있을 것이다.