The role of prestress and its optimization in cable domes design

M. Quagliaroli, P.G. Malerba, A. Albertin, N. Pollini (Politecnico di Milano, Studio Malerba, Technion – Israel Institute of Technology)

CHALLENGE - Among hybrid tensile structures, cable domes are widely used as lightweight, versatile forms of roofing in architecture. This study explores the role of prestress and its optimization to increase the stability and design efficiency of cable domes. 

SOLUTION - A comparative analysis was done on the performance of braced cable domes, whose bearing capacity is due to mechanical stiffness, and prestressed structures, whose bearing capacity is also due to the geometrical stiffness provided by prestress. An optimal solution was reached with the help of a numerical approach based on genetic algorithm. Results show that applying prestress allows designing lighter, even unconventional structural schemes. Additionally, certain results achieved by the use of prestress cannot be reached by the usual braced domes. 





















BENEFITS - In order to provide a design solution not only technologically sound, but also optimal with respect to design requirements, a structural optimization process is proposed using the genetic algorithm (GA), a heuristic search technique belonging to the class of stochastic algorithms, implemented in modeFRONTIER. By using the optimization software researchers were able to consider also the horizontal reactions and design supporting structures both equilibrating the the vertical loads and carrying the shrinking effects due to the prestress.