Title Analysis of Seismic Response Control Performance of Outrigger Systems in Tilted Irregular High-Rise Buildings
Authors 김지현(Kim, Ji-Hyeon) ; 이다혜(Lee, Da-Hye) ; 강주원(Kang, Joo-Won)
DOI https://doi.org/10.5659/JAIK.2025.41.12.311
Page pp.311-318
ISSN 2733-6247
Keywords Tilted Shaped Structure; Outrigger System; Seismic Response; Structural Stability
Abstract Tilted structural systems, intentionally designed with inclined forms, may experience eccentricity and overturning moments under gravity loads due to a mismatch between the center of mass and the center of rigidity. Consequently, lateral displacements can be induced not only by lateral loads but also by gravity loads. Therefore, in structural design, it is essential to examine the member forces and deformations of critical members under irregular load paths. In this study, the optimal installation locations of outrigger systems in irregular high-rise buildings with tilted geometries were investigated, and their effectiveness in controlling seismic responses was analyzed. To this end, a set of 90-story analysis models were developed, each with varying in the number and vertical position of inclined stories. Each model was designed to limit wind-induced lateral displacement to within 1/500 of the building height. Subsequently, the natural period, displacement responses, and axial forces in external columns and shear walls were analyzed. As a result, the optimal outrigger installation positions in the tilted structures were located between 0.411H and 0.489H from the top of the building. The displacement response was more effectively reduced when the core had a larger contact area along the inclined direction. However, as the inclination angle increased and the inclined section was positioned lower, the effectiveness of controlling axial forces and displacement responses diminished. Although the response-reducing effect of outrigger installation was observed, the effect was relatively limited.