Ultimate strength behavior of curved steel–concrete–steel sandwich composite beams

Abstract

A concept of using curved steel–concrete–steel (SCS) sandwich structure as the ice-resistant wall has been proposed for Arctic oil and gas drilling platform. In the developed curved SCS sandwich structure, ultra-lightweight cement composite (ULCC) and overlapped headed studs were used as the core material and bonding measures at the steel-concrete interface, respectively. In this paper, quasi-static tests on ten curved SCS sandwich beams have been carried out to investigate their ultimate strength behaviors under patch loading that considers the critical local ice-contact pressure. The test results reported the failure mode and shear resistances of structures, studied the influences of thickness of the steel skin shell, curvature, spacing of the connectors, depth of the cross section, strength of core materials, and boundary conditions on the ultimate strength behavior of the curved SCS sandwich beam. Extensive discussions and analysis were also carried out to provide information for the development of the analytical models. Analytical models were developed through modifying design code provisions. These innovative modifications in the analytical models included redefining the inclination angle of shear failure surface, redefining the effective depth of the section, considering the influence of the thickness of steel skin, and developing analytical models on tensile resistance of the overlapped headed studs. The accuracy of the predictions by the analytical models was checked by the test data. All these efforts were made to provide better predictions on the shear resistance of the curved SCS sandwich beam.