Abstract
The purpose of this study is to analyze lateral load resisting capacity by core area ratio of tower-shaped type apartment with flat plate system and to find an effective core ratio to control lateral displacement of tower-shaped type apartment with flat plate system. In tower-shaped type apartment with flat plate system, the core wall has an important role of controlling lateral displacement. When the spacious core area is good for controlling lateral displacement, but residential area will become small. Contrary, small core area has disadvantage in lateral displacement, but residential area will become more spacious. This study uses analysis program, Midas Gen. Core area ratio is five, from 11% to 22%. As a result, when the core area ratio is 22%, lateral displacement is declined 60% than 11%. And according to raising core area, the residential area is become small. But the amount of concrete decrease by raising the core area. So in a point of economic view, raising the core area is not an important role in effectiveness of structure.