Abstract

The fundamental problem while obtaining initial modulus (Young’s modulus) of concrete in experimental studies is to determine the region on stress-strain curve that will be used in calculations of initial tangent. In the present paper, an approach that depends on regression control chart - that is one of the statistical process control (SPC) tools - for determining the initial tangent and Young’s modulus is proposed. The aim of this study is to determine Young’s modulus from a particular region on stress-strain curve, which is determined by monitoring the experimental data obtained from an experimental set-up, with regression control chart.  According to the current standards, Young’s modulus of concrete and steel materials is given individually. There is no established young’s modulus exists for reinforced concrete sections. For the displacement calculations, the elasticity modulus is used which is calculated by considering only the compressive strength of concrete. However, steel reinforcements are contained here too. In the relevant literature, there exists no study that uses statistical process control charts to determine the Young’s modulus of data obtained from experimental experience with reinforced concrete specimens. The results demonstrate that the Young’s modulus values calculated by proposed method correspond with values calculated by analytical method.

Key words: Reinforced concrete columns, stress-strain models, Young’s modulus, regression control chart.

Abbreviation

: , Standard deviation of population; ,  Standard deviation of residuals; , Random error term; , Intercept of regression equation; , Slope of regression equation; , Time (or observation number); , Residual at time t.