Confinement effects for rubberised concrete in tubular steel cross-sections under combined loading

Abstract This paper describes an experimental investigation into confinement effects provided by circular tubular sections to rubberised concrete materials under combined loading. The tests include specimens with 0%, 30% and 60% rubber replacement of mineral aggregates volume. After describing the arrangements specimen details, results bending eccentric compression are presented, together complementary axial on stub-column samples. Tests hollow steel also included for comparison purposes. Particular focus is given assessing in infill as well their influence axial–bending cross-section strength interaction. show that whilst capacity reduced increase ratio, enhanced action obtained high content compared conventional materials. Test measurements means digital image correlation techniques neutral axis position loading depend content. Analytical procedures determining infilled cross-sections considered based test those from a collated database then available recommendations. Rubber content-dependent modification factors proposed provide more realistic representations flexural capacities. observations used, conjunction number analytical assessments, highlight main parameters influencing behaviour propose simplified expressions bending.