Sustainability Optimization: Assessment of Recycling Scenarios for Timber-Concrete Hybrid Slabs

Over the last years, increasing awareness of the alarming proximity to critical climate tipping points is spreading, along with the knowledge that implications for the whole humanity would be exacerbated in case these limits are overcome. Thus, a series of international actions that also involve a rethinking of traditional steps for design, maintenance and dismantling in civil engineering applications initiated. One of the most demanding targets is to include environmental assessment of a structure already in the design phase to equate sustainability with other driving parameters, as e.g., economic benefits. Reduction of environmental impact cannot be reduced to a mere calculation, but it should be exploited for seeking new structural solutions in a comprehensive scenario. In such scenario, a composite slab made by concrete and engineered timber (Timber Concrete Composite, TCC) is a valuable answer to decrease environmental impact of such horizontal element, improving its rigidity, stiffness, and load-bearing capacity. In this context, a broad outlook supports a specific focus on uncertainties that may affect Life-Cycle Assessment (LCA) results: evaluation of multiple scenarios is the key to smooth uncertain data pertaining service life or End-of-Life events. Assessment of multiple scenarios allows for consideration of burdens and benefits currently treated as non-standard option, as e.g., mixed End-of-Life scenario exploiting both timber and concrete carbon capture inborn ability. In this way, the composite slab is used as concrete layer optimizer since the rationale behind this research pursues minimization of materials quantities through achievement of maximum environmental and structural performances. To deliver robust results, two sets of potential solutions are analzyed, characterised by the same bearing capacity or the same span, respectively.