Structural Performance of Demountable Hybrid Floor Systems Under Monotonic and Cyclic Loading

The building sector is actively researching and reviewing technical solutions for de-construction, driven by the increasing importance of sustainability requirements, as outlined in the EU Commission's ‘Green Deal,‘ which aims to achieve net-zero greenhouse gas emissions by 2050. Two key research areas in efficient structural design strategies are the performance of hybrid structures, which combine mechanical properties and architectural appearance of different materials, and the techniques and mechanical properties of connections between structural components that enable deconstruction and reuse. However, there is a scarcity of studies and methods focused on demountable and hybrid structural systems, limiting the understanding of their overall structural performance at a real-structure floor level. In this paper, a finite element model is presented to conduct a comparative study between the traditional floor system with welded stud connections and the demountable floor system with coupler-embedded bolted connectors. The numerical results showed that the serviceability loading capacity of the demountable floor system was 8% lower, and the difference in ultimate resistance was further enlarged. Reusing a demountable floor system, analysed in the case study, had little effect on the ultimate resistance, but it is difficult to exclude local plastic deformation after the first life cycles.