Optimal Design of Tall RC‐Framed Tube Buildings

Abstract

Analysis and design of reinforced concrete (RC) framed tube buildings is formulated as a general nonlinear optimization problem and solved using modern design‐optimization algorithms and software. A brief review of tall‐building‐design considerations and framed tube behavior is presented as well as a discussion of the analysis methods employed. Nonlinear effects due to large displacements are treated using an approximate iterative method. Column and beam dimensions and their steel areas are treated as design variables. The dollar cost of the framed tube, consisting of the cost of beam concrete, column concrete, reinforcing steel, and the formwork, is treated as the objective function to be minimized. Constraints for the problem consist of building drift, fundamental frequency, requirements of the American Concrete Institute, and explicit bounds on the design variables. Various software components are integrated to create the design‐optimization capability.