Tests on Circular Thin-Walled Steel Tubes Filled with Medium and High StrengthConcrete

摘要

This report presents the results from an experimental study performed toinvestigate the behavior of short circular thin-walled steel tubes filled with medium and high strength concrete. Five different circular steel tubes were examined with a diameter to thickness ratio ranging from fully effective to slender where local buckling of the steel tube dominates the behavior. Two nominal concrete strengths of 50 MPa and 80 MPa were used to fill these steel tubes. The material properties, residual stresses and geometric imperfections were carefully measured. Three different axial compression tests were conducted which included: concentrically loading the steel and concrete simultaneously; concentrically loading only the concrete (steel unbonded and only used as confinement) and eccentrically loading the steel and concrete simultaneously at eccentricities of D/20 and D/10, where D is the external diameter of the steel tube.