Sensitivity Study of Optimum RC Restrained End T‐Sections

Abstract

Economical restrained end reinforced concrete T‐sections are established using an optimization routine and the strength design procedure. The objective function includes the in‐place cost of formwork, concrete, longitudinal reinforcement, stirrup reinforcement, and depth‐related costs. The continuous function design variables are the beam stem width, effective depth, areas of tension and compression reinforcement, and percentages of support moment redistribution. Linear and nonlinear continuous functions are applied to establish side and behavorial constraints. The behavorial constraints include the nominal moment and shear strengths at critical locations and deflection limitations. Comparisons of optimum beam designs, obtained by changing a particular design parameter, are made to indicate design sensitivity. These parameter studies show the individual effects of allowable deflection, material strengths, support continuity, and unit material cost variation. The paper concludes with guidelines for economical T‐sections that are based on the results of the parameter sensitivity studies.