| Title |
In-plane Free Vibrations of Horseshoe Circular Arch |
| Authors |
이병구(Lee, Byoung Koo) ; 오상진(Oh, Sang Jin) ; 이태은(Lee, Tae Eun) |
| DOI |
https://doi.org/10.12652/Ksce.2014.34.4.1043 |
| Keywords |
마제형 아치;원호 아치;면내 자유진동;곡선거리좌표;고유진동수;진동형 Horseshoe arch;Circular arch;In-plane free vibration;Arc length coordinate;Natural frequency;Mode shape |
| Abstract |
Flexible base isolation bearings that separate superstructure from ground have been widely used in the construction field because they make a significant contribution to increasing the fundamental period of the structure, thereby decreasing response acceleration transmitted into the superstructure. However, the established bearing devices installed to uphold the whole building give rise to some problems involved with failure and collapse due to lack of the capacity as modern structures are getting more massive and higher. Therefore, this study suggests new isolation bearings assembled with additional restrainers enabled to reinforcing and recentering, and then evaluates their performance to withstand the seismic load. The superelastic shape memory alloy (SMA) bars are installed into the conventional lead-rubber bearing (LRB) devices in order to provide recentering forces. These new systems are modeled as component spring models for the purpose of conducting nonlinear dynamic analyses with near fault ground motion data. The LRB devices with steel bars are also designed and analyzed to compare their responses with those of new systems. After numerical analyses, ultimate strength, maximum displacement, permanent deformation, and recentering ratio are compared to each model with an aim to investigate which base isolation models are superior. It can be shown that LRB models with superelastic SMA bars are superior to other models compared to each other in terms of seismic resistance and recentering effect. |