Structural Design and Performance of Braced Magatubes for Supertall Buildings

초록

Among various tubular systems developed for tall buildings, braced tubes with perimeter columns and large diagonal bracings can provide one of the most efficient structural solutions. Compared with the conventional braced tubes with regularly spaced multiple perimeter columns on every side of the building, braced megatubes with corner megacolumns are more efficient in resisting lateral wind loads. Structural design of tall buildings is generally governed by lateral stiffness. Depending on the stiffness distribution, the level of efficiency between different structural systems can vary substantially. This paper studies optimal structural design of braced megatubes in comparison with that of conventional braced tubes based on the optimal stiffness distribution for each. With the optimally designed structures, comparative efficiency between the systems is also evaluated. The heights of the comparatively studied braced tubes and braced megatubes range from 40 to 120 stories. These structures' height-to-width aspect ratios are between 4.3 and 13. While emphasis is placed on the optimal structural design and comparative structural efficiency of the braced tubes and braced megatubes, architectural design considerations are also discussed holistically.