Evaluation of flexural cracks in reinforced concrete members

Abstract

A research program was conducted with the aim of studying the cracking behavior of concrete beams under increasing load and to study this behavior as it is affected by using combinations of steel reinforcement of different grades The yield strengths of the steel bars used were 40 50 60 75 ksi and the ultimate strength of cables was 250 ksi Widths and spacings of cracks as well as strains in steel reinforcement were measured all due to two cycles of loading An expression for the calculation of the maximum crack width and another expression for the spacings of cracks were developed A graph was established to estimate the maximum crack width for a known steel stress and percentage The graph is the result of this research and the relations obtained by other investigators