Reusability assessment of reinforced concrete components prior to deconstruction from obsolete buildings

A large part of building demolitions is motivated by purely socio-economic reasons. Hence, about-to-be-demolished structures, commonly made of reinforced concrete, very often present no or little degradation. When adaptive reuse of the entire building is not possible anymore, its deconstruction and the reuse of its load-bearing components elsewhere in new structures maximize the reclamation of preexisting structural qualities. This strategy drastically decreases the environmental burden of both demolition and subsequent new construction. However, its efficient implementation requires a careful preliminary assessment of the existing structure, including the inventory of its components, and the evaluation of their reuse potential in relation with their pre-existing damages and possible future uses. Currently available procedures are not exhaustive and focus solely on precast components. This paper thus introduces a specific methodology for the reusability assessment of load-bearing reinforced concrete components, focusing in priority on their long-term durability. It first proposes a systematic protocol to classify and quantify the components, investigate their geometrical and material properties and evaluate their preexisting damages. Then, the paper develops a new procedure to grade the reusability of the components for future projects. Finally, the whole methodology is tested on three case studies in Switzerland, demonstrating its robustness and repeatability. In these three case studies, 95 % of reinforced concrete components are graded as reusable.