New confining stress-based design for rubberised concrete-filled single/double-skin steel tubular short columns

Abstract

Despite being characterised by a reduction in compressive, tensile and flexural strengths when compared to standard concrete, rubberised concrete (RuC) is being used as a way to conserve natural resources and reduce the amount of tires entering landfills. An excellent solution to limit the RuC's compressive strength drop is to incorporate this type of concrete into steel tubes. However, up-to-date there is a lack of lateral confining pressure formulae for square and circular rubberised concrete-filled steel tubular (RuCFST) columns and rubberised concrete-filled double-skin steel tubular (RuCFDST) columns. Hence, the main aim of this technical note is to provide new design formulae based on lateral confining pressure and calibrated by means of test results available in the literature. These formulae are then used to suggest more accurate design strength models compared to those obtained from European, American and Australian specifications.