Optimization of concrete cable-stayed bridges under seismic action

A computational tool is presented for the optimum design of concrete cable-stayed bridges under seismic action. The finite element method is used for the three-dimensional analysis of the structure under dead and live loads, time-dependent effects and geometrical nonlinearities are considered. The dynamic analysis is solved by the modal/spectral approach. The design problem is posed as a multi-criteria optimization. The design variables are the cable forces and the cross-sectional dimensions of cables, deck and towers. Design objectives of minimum cost, deflections, natural frequencies and stresses considering both, serviceability and ultimate limit states are considered. Given that a gradient-based algorithm is applied for the optimization the discrete direct method is used for sensitivity analysis. An entropy-based algorithm finds economically and structurally efficient solutions by rearranging the stiffness and mass distribution to enhance the structural response. Numerical examples illustrate the features of the proposed computational tool. (C) 2019 Elsevier Ltd. All rights reserved.