Behaviour of demountable steel‐concrete composite beams with bolts and headed studs

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.