Experimental evaluation of new concrete encased steel composite beam to steel column joint

Abstract

To reduce the floor-to-floor height, the technical, economical, and convenient (TEC) beam is developed as a new composite beam composed of structural tee, horizontal top stud, precast concrete, stirrup, and cast-in-place concrete slab. The preliminary testing of the proposed system was performed for simple beams, and the results indicated good structural behavior. However, application of the system in the relevant field requires the development of a moment-resisting connection using steel brackets on which upper rebars of the TEC beam are anchored. In this paper, three types of the proposed system are experimentally investigated under cyclic loadings. The parameters of the test are the spacing of transverse bars in the slab and the ratio of width of rebar spacing to bracket length. The structural behaviors such as load-displacement relation, ductility, variation of neutral axis, and failure pattern, were explored. Based on test results, specimens were classified as semirigid full strength by the Eurocode 4. It could be concluded that the proposed moment-resisting system shows good structural behavior and may be applicable in the field.