Optimal Angle of Diagrid Structures for High Rise Buildings

Abstract

The rapid growths of urban population and consequent pressure on limited space have considerably influenced the developments of the high rise buildings. As the height of building increases, the lateral load resisting system becomes more important than the gravitational load resisting structural system. The widely used lateral load resisting systems are: rigid frame, wall-frame, brace tube frame, outrigger system and tubular system. Diagrid structural system is also emerging as an effective lateral load resisting system because of its triangulated configuration. Recently, diagrid structural system is widely used for tall buildings due to its structural efficiency and aesthetic potentials. Diagrid is a form of space truss. Diagrid structural system doesn’t have a vertical element for lateral load resistance and it consists of inclined columns on the exterior surface of the buildings. Inclined column resist gravitational load as well as lateral loads. Lateral load is resisted by axial action of inclined columns on the periphery of building. In present study, optimal angle of inclined columns in diagrid structural system is evaluated. For this purpose 40, 50, and 60 storey tall buildings are considered with different angle of inclination of diagonal column on periphery like 50.2, 67.4, 74.5, 78.2, and 80.5 degrees with 2, 4, 6, 8, and 10 storey modules respectively. The angle of inclination is kept uniform throughout the height. The modeling, analysis and design of diagrid system with different height are carried out using ETABS software.