Multi‐objective optimization of reinforced concrete columns considering long‐term and second order effects: Constructability, cost, and environmental impact

Abstract This work presents a methodology for the optimum design of reinforced concrete (RC) columns subjected to axial compression and bending end loads, considering long‐term and second‐order effects, designed according to the general method outlined in Eurocode 2 (EN 1992‐1‐1, 2004). The approach is applicable to columns of any slenderness, with arbitrary polygonal cross‐section shape and subjected to any combination of axial compression and bending end loads. The multi‐objective problem is formulated for the simultaneous improvement of cost, constructability, and environmental impact. The solution is obtained by the metaheuristic algorithms multi‐objective quantum particle swarm optimization (MOQPSO), multi‐objective particle swarm optimization (MOPSO) and the well‐established non‐dominated sorting genetic algorithm II (NSGA‐II). Examples of the optimization of RC columns with rectangular cross‐section and subjected to many load cases showed that cost and environmental impact can be minimized simultaneously at the expense of constructability, which is observed by the non‐linear Pareto frontier obtained for each pair of these conflicting objectives.