PSI - Issue 64

Raul Berto et al. / Procedia Structural Integrity 64 (2024) 1733–1742 1737 Raul Berto, Chiara Bedon, Andrea Mio, Alessandro Mazelli, Paolo Rosato / Structural Integrity Procedia 00 (2019) 000 – 000 5

Table 2. Economic parameters. Solution Implementation cost Decommissioning cost OSB 14,791.92 € 5,036.16 € CLT 31,067.80 € 6,043.39 € LWC 14,848.27 € 11,289.60 € Table 3. Architectural parameters. Solution Reversibility Invasiveness OSB 10 6 CLT 10 8 LWC 4 1

Environmental parameters: The LCA methodology is used to estimate the environmental emissions of products throughout their entire lifespan (Mio et al., 2022;2023). For the purposes of this study, the functional unit was defined as “the production, installation and final disposal of a structural reinforcement for the restoration of a historic building”, using a cradle -to-grave approach. Raw materials, manufacturing activities, average European transportation and end-of-life treatments were retrieved from the Ecoinvent v3.10-Cutoff database and openLCA software was used for calculations. Installation and lifetime maintenance impacts were considered negligible, as they fall below the 1% cut-off. Results are reported in Table 4, using the aforementioned impact categories (GWP100 and AWARE). Table 4. Environmental parameters. PRODUCTION STAGE END OF LIFE STAGE Solution GWP [kg CO 2 eq] % Water use [m 3 ] % GWP [kg CO 2 eq] % Water use [m 3 ] % OSB 4,297.99 88.15 1,830.00 100 578.05 11.85 0.00 0.00 CLT 5,056.83 95.21 2,120.00 97.00 254.17 4.79 65.71 3.00 LWC 6,312.66 92.94 2,250.00 92.49 479.35 7.06 182.24 7.51 Structural parameters : The static benefits of floors strengthening solutions were assessed for Serviceability (SLS) and Ultimate Limit State (ULS) , according to the γ -method (EN 1995-1-1:2005, 2005). A safety factor for SLS (SF SLS ) was defined as the ratio between the instantaneous deflection under a live load q=3.00 kN/m 2 and the limit value of L/300 (Italian Building Code, 2018), where L is the span. The ULS performance was evaluated as the load carrying capacity of the floor. A safety factor for the ULS (SF ULS ) was also identified, considering the ratio between the maximum live load carried by the floor and the q=3.00 kN/m 2 load. Δ static for SLS and ULS were calculated as: ∆ , [%]= , − , , ∙ 100 ℎ = (6) where “pre” and “post” refer to “ before ” and “ after ” the intervention. Furthermore, the variation over time of Δ static was considered. A creep coefficient was applied to all the components (panels, slab and connections), except for existing timber beams. The coefficients for timber were chosen according to Toratti (1992) and EN 1995-1-1:2005 (2005), whereas for LWC according to Jiang et al. (2021) and EN 1992-1-1:2004 (2004) . The values Δ static were calculated after 15 and 50 years. The performance under seismic excitation was evaluated considering both the out of-plane wall mechanisms and pushover analyses (Sap2000). The mechanical parameters for the timber reinforcement were taken from (Gubana and Melotto, 2021b), with E= 20 GPa the modulus of elasticity of LWC. The increase in seismic performance was evaluated in relation to DL and LS limit states: ∆ , [%]= , − , , ∙ 100 ℎ = (7) where ζ is the ratio between the capacity and the demand in terms of PGA, before (pre) and after (post) the intervention. The seismic performance was taken as constant over time (Gubana et al., 2023). The obtained values of Δ for all cases are in Table 5, while the analysis matrices are reported in Table 6.