The structural modelling of deconstructable beams, fabricated using friction-grip shear connection

Many new medium-sized office-building structures are “temporary” and in some cases are demolished within ten years of their construction. Composite steel-concrete structural systems are very popular for medium-sized office buildings, but deconstruction and re-use in deference to demolition is difficult because headed stud shear connectors in the composite slab and steel beam flooring system cannot be detached easily, and reuse is virtually impossible. As an alternative, it is proposed that precast concrete panels can be attached to steel beams using pre-tensioned bolts, instead of cast-in-situ floors with pre-welded headed stud connectors. The proposed floor system can be deconstructed by unbolting the precast panels, enabling recyclability of the system and providing significant advantages in a paradigm within the construction industry focussed on low emissions. This paper presents an analysis of this slab and beam system, with the composite beams comprising of two elastic elements connected at their interface by a stiff but finite frictional connection. Under loading, it is shown that three distinct lengthwise domains exist along the member, and a model for this is presented and discussed.