Comparison of metaheuristics on multi objective (Cost-C02) optimization of RC cantilever retaining walls

Abstract

In this study, performance of meta-heuristic methods on optimum design of reinforced concrete (RC) retaining wall has been investigated with respect to minimizing the cost and the CO2 emission. Biogeography Based Optimization (BBO) and Social Spiders optimization (SSO) methods utilized for investigation. The minimizations of the cost, the CO2 emission and multi-objective of the cost+CO2 functions are described as objective functions of the optimization problem. There are thirteen design variables are defined in the optimization problem. Eight of these variables are the cross sectional dimensions of the retaining wall. The other five design variables are the reinforcement detailing of wall members. Flexural and shear strength requirements, minimum and maximum cross section areas of the reinforcement bar, the requirement length for reinforcement details and the factor of safety for failure modes are defined as constraints functions of the optimization problem. The Flexural and shear strength requirements, minimum and maximum limitations of the reinforcement bar areas are adopted from American Concrete Institute (ACI 318-14) design code. In order to test performance of the presented optimization methods literature design examples are used. In addition, efficiency of steel and concrete classes on optimum CO2 emission and cost have been investigated by using different steel and concrete classes.