Assessment of crack width estimation models for RC tension members

Abstract

The objective of this study is to assess the crack width estimation equation suggested in CEB-FIP Model Code 1990 (1991) in terms of concrete strength. To evaluate the crack width estimation equation, a numerical model for a crack element is introduced by adopting detailed bond stress slip models. A remarkable advantage of the use of the model is that all significant internal variables within a crack element can be analysed, including average bond stress and tension stiffening effect, which are the vital parameters for the equation in CEB-FIP Model Code. Experimental results from literature were compared with those obtained by the estimation model equation in CEB-FIP Model Code and by the numerical analysis using the crack element model. The average bond stress and tension stiffening effect given in CEB-FIP Model seem to be overestimated and thus need to be reduced to properly reflect the effect of concrete strength.