Durability Design of Reinforced Concrete Beams Using Cost Minimization by Excel Solver

Abstract

Design procedures based on current specifications do not always ensure required service life, mostly because of the underestimated durability parameters. This is due to the fact that definition of durability is not operational as basis for design, maintenance and repair. This paper presents an Excel spreadsheet model for the cost optimization of simply supported beams designed according to the requirements of the American Concrete Institute (ACI) code and the Japan Society of Civil Engineers (JSCE) recommendation. The resulting structure, however, should not only be marked with a low price but also comply with all strength and durability requirements for a given level of the applied load. Cover depth and water to cement ratio (w/c ratio) are considered as durability design variables to define life time of the structure.
Keywords: cover depth, life time, diffusion coefficient, cost minimization