Experimental investigation of composite floor system with thin-walled steel trussed beams and partially prefabricated concrete slab

摘要

The present investigation addresses the structural behavior of steel and concrete composite floor systems, composed of thin-walled trussed members, usually adopted in the steel frame constructional technology. The floor systems of typical light-weight frame constructions are generally constituted by thin-walled beams (or open web joist), wood-based panels (Oriented Strand Boards - OSB) and self-drilling screws connecting both materials (steel and wood). In some situations, concrete slabs are cast over the OSB panels and no shear connectors are adopted to ensure the composite action between the steel members and the concrete. In this context, one of the objectives of this work aims at presenting three new innovative solutions for shear connectors, composed of thin-walled members and attached to the top chord of the trusses by means of self-drilling screws (4.2 mm diameter). A series of experimental tests were performed in the Structures Laboratory of Federal University of Rio de Janeiro (COPPE/UFRJ), in order to provide reliable information in terms of shear strength, deformation capacity and mechanisms of collapse associated with eight push-out test specimens, according to recommendations established by Eurocode 4. Also, the performance of the referred connectors was investigated with the help of three full-scale bending tests, which revealed important characteristics regarding the structural behavior of the composite floor systems in terms of bending capacity, flexural stiffness, degree of interaction between the steel trusses and the concrete slabs, as well as strain distribution at mid-section. (c) 2020 Elsevier Ltd. All rights reserved.