Development of a holistic parametric framework for multi-performance evaluation of post-tensioned timber buildings

Catastrophic events and climate change represent major challenges for modern society, which calls for new solutions able to provide acceptable performances with low carbon footprint. In the European Union (EU), the building and construction sector accounts for 36% of the total EU operational energy, and 39% of Carbon Dioxide (CO2) emissions (GlobalABC, IEA, UN Environment Programme, 2019). This aspect becomes much more important in seismic-prone areas, where buildings are vulnerable to extensive damage which significantly impacts the sustainability of the environment as well as the resilience of the entire community (Menna et al., 2013). Indeed, recent catastrophic earthquakes have once again emphasized the mismatch between social expectations over the seismic performance of modern buildings, proving the need for a shift towards a damage-control approach using low-damage technologies. Post-tensioned engineered timber structural system, also known as Pres-Lam (Prestressed Laminated timber), meets the need for an outstanding seismic structural performance using sustainable materials (Palermo et al., 2005, Granello et al., 2020). Besides the material choice, the design phase has a strong influence over the environmental impact along the life-cycle of buildings; hence, the decision-making process has to take into account multiple aspects related to the proposed solution that has to be combined into a comprehensive framework. To date, numerous procedures have been proposed to evaluate the seismic performance and environmental impact in the construction sector (the second, using Life-Cycle Assessment (LCA) regulated by ISO 14040 and ISO 14044 (Caruso et al., 2017)), but these are rarely considered simultaneously. Thus, this paper proposes a holistic parametric approach able to assess those different aspects, developing an integrated model in Rhino-Grasshopper environment using independently developed packages. Seismic and environmental performance are evaluated for three different Pres-Lam case studies. The seismic response is assessed through a probabilistic approach, whereas the carbon footprint is estimated using the extensive environmental database of the Grasshopper plugin One Click LCA. Given the parametric nature of the framework, a wide range of solutions can be analyzed in order to make the optimal choice, with the possibility to include also energy simulations and combine all of the results within a Multi-Criteria Decision Analysis to guide the decisional process.