A constitutive model for predicting the lateral strain of confined concrete

Depending on the confining stress developed, the provision of confinement can substantially improve the strength and ductility of concrete members. However, the confining stress developed is related to the lateral strain (or lateral expansion) of the concrete and up to now it remains a difficult task to evaluate the lateral strain of confined concrete under inelastic condition. Herein, the lateral strain of confined concrete for the full stress-strain range from pre-crack and elastic state to post-crack and inelastic state is studied based on published experimental results, and a constitutive model for predicting the lateral strain of confined concrete is developed by back calculation from the experimental results. This model is a useful tool for analyzing the full range structural behaviour of various kinds of confined concrete columns and concrete-filled steel tube columns.