Simplified Model for Analysis and Optimization of Skyscrapers with Outrigger and Belt Trusses

Abstract

A simplified skyscraper model (SSM) based on dominant degrees of freedom and superelements was developed and implemented in a spreadsheet for use in preliminary design of skyscrapers with outrigger and belt trusses. The SSM was used to analyze and optimize the linear and nonlinear response to gravity, wind, and seismic loading of four configurations of an example 100-story skyscraper. Results from the SSM were compared with those from a detailed finite element model (DFEM), and the difference was less than 1% for displacement and 6% for maximum stress. The SSM properly predicted the deflected shape of the core including curvature reversals typical of skyscrapers with outrigger and belt trusses. The speed of execution, data preparation, data extraction, and optimization were found to be much faster with the SSM than with the DFEM.