Thesis (M. Eng.)--Massachusetts Institute of Technology, Dept. of Civil and Environmental Engineering, 2006.Includes bibliographical references (leaf 60).The need and ambition of humanity to go higher and higher is something that is amplified as time evolves. It is the same need that leads engineers to push their structures to higher limits. However, when engineers design higher structures their knowledge and their abilities are challenged. In that sense, during the design process of a high-rise building all the strange phenomenon of the behavior of the structure must be considered. A very significant factor that affects the limits of today's high-rise construction is the wind loading. Bracing the building in a clever and more efficient way was always a difficult task for designers and engineers. This thesis deals with a bracing system called the knee-bracing system. The application of knee-bracing system for high-rise buildings is not yet fully determined and this study will try to describe the problem and provide some solutions. Knee-bracing will be checked and the possibility of providing the required results using the minimum amount of material and giving the maximum space for use from the residents or workers of the building will be examined.(cont.) Several different cases of loading and knee-bracing systems are considered and an optimization for the design of such systems is described. The last part of the document describes the idea of adaptive stiffness, something new for high-rise buildings. Reinforcing these ideas, solutions for the construction of these bracings are also provided.by Symeon Gerasimidis.M.Eng
