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Implementation of demountable beams in steel‐concrete composite floors enables structure reuse during several life cycles, consequently leading to savings in material consumption and reduction of emissions, providing overall ecological benefits. The behaviour of the innovative demountable beam with a shear connection consisting of headed studs and bolts is analysed in this paper. The proposed beam is formed of a steel profile and a steel‐concrete composite slab cast in open trough profiled steel sheeting. Headed studs, welded to the additional steel angles, are placed in sheeting ribs, whereas bolts are installed between ribs, connecting the steel angles and profile flange. A numerical FE model of a full‐scale steel‐concrete composite beam has been developed to analyse the beam behaviour under service loads. Experimental results of push‐out tests have been used to describe the load‐slip behaviour of headed studs, whereas bolt response has been simulated according to the experimental investigations of lap joints with preloaded bolts and oversize holes. The parametric study has been conducted by varying the bolt diameter, grade and bolt hole size. The results have validated the applicability of the proposed system, confirming the fulfilment of serviceability limit state requirements. [ABSTRACT FROM AUTHOR]

For obtaining shear resistance of a welded headed stud in profiled steel sheeting, EN 1994‐1‐1:2004 defines reduction factors that should be multiplied with the resistance of a headed stud in a solid concrete slab. Two reduction factors are prescribed, for sheeting ribs that are parallel and transverse to the supporting beam. However, the design code does not recognise cases when the angle between ribs and the beam is in the range between 0° and 90°. This research is focused on the specific case in the steel‐concrete composite beam design when the angle between profiled sheeting ribs and the beam is 45°. The experimental investigation has been conducted through push‐out tests, comparing the response of the connection with a rib‐to‐beam angle of 45° and the connection with ribs transverse to the supporting beam. In addition, numerical models based on finite element analysis have been made and validated against experimental data. According to the obtained results, similar failure mechanisms manifested through concrete pull‐out failure and separation of the concrete cone are observed in shear connections with rib‐to‐beam angles of 45° and 90°. An increase in the connection resistance is noticed with the decrease of a rib‐to‐beam angle. [ABSTRACT FROM AUTHOR]