OPTIMAL DESIGN OF NON-PRISMATIC REINFORCED CONCRETE BOX GIRDER BRIDGE: MINIMIZATION OF THE COST AND CO2 EMISSION

This paper presents a computational framework for optimal design of non-prismatic reinforced concrete box girder bridges. The variables include the geometry of the cross section, tapered length, concrete strength and reinforcement of box girders and slabs. These are obtained by the enhanced colliding bodies optimization algorithm to optimizing the cost and again CO2 emission. Loading and design is based on the AASHTO standard specification. The methodology is illustrated by a three-span continuous bridge. The trade-off between optimal cost and CO2 emission in this type of bridge indicates that the difference of costs, as well as CO2 emissions in the solution with both objectives is less than 1%. However, the optimal variables in the cost objective are different from the variables of CO2 emission objective.