PSI - Issue 78

Raffaele Laguardia et al. / Procedia Structural Integrity 78 (2026) 678–685

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Figure 5 shows the decomposition of the LCCI in the purely economic part (i.e., C I + C S ) and the purely environ mental part (i.e., ( I I + I S ) CT ) and it clearly shows that the environmental term impact on the LCCI is marginal, despite the CT value adopted (i.e., 120 e / ton ( CO 2 , eq )) is the highest values nowadays adopted by governments (World Bank, 2023).

Fig. 5. Cost breakdown between economic and environmental part of the OF function

4. Conclusions

This paper presents an optimization procedure for the design of bracing systems on existing RC buildings con sidering sustainability-based metrics for performance assessment. The objective function considers economic and environmental losses due to seismic events, along with initial costs and impacts due to retrofit intervention. At the same time, the constraint function allows to satisfy safety requirements expressed in terms of MAF of collapse limit state. The structural performance assessment is done using Modal Response History Analyses and a SAC-FEMA approach, thus considering uncertainties and reducing computational burden. The procedure has been applied to an existing low-code RC building, by the means of this example it has been shown how the procedure provides an opti mal configuration of brace property both in plan and elevation ensuring minimization of economic and environmental costs while safety requirements are fulfilled. Nonetheless, the influence of the environmental part was marginal and the design was highly dominated by the economic part. This appears as a strong limitation of an economic equiva lent sustainability approach because it does not allow to make relevant the environmental part in the decision-making process, at least considering the Carbon Tax values adopted herein. Abruzzo, R., 2023. Price list of civil manufacturing (italy, abruzzo). Aljawhari, K., Gentile, R., Galasso, C., 2024. Earthquake-induced environmental impacts for residential italian buildings: Consequence models and risk assessment. Journal of Building Engineering 84. doi: 10.1016/j.jobe.2023.108149 . Asdrubali, F., Baldassarri, C., Fthenakis, V., 2013. Life cycle analysis in the construction sector: Guiding the optimization of conventional italian buildings. Energy Buildings 64, 73–89. doi: 10.1016/j.enbuild.2013.04.018 . ATC, 2012. FEMA P-58-1 Seismic Performance Assessment of Buildings - Methodology. volume 1. Federal Emergency Management Agency (FEMA), Washington D.C. Baker, J.W., Cornell, C.A., 2008. Uncertainty propagation in probabilistic seismic loss estimation. Structural Safety 30, 236–252. doi: 10.1016/ j.strusafe.2006.11.003 . Braga, F., Gigliotti, R., Laguardia, R., 2019. Intervention cost optimization of bracing systems with multiperformance criteria. Engineering Structures 182, 185–197. doi: 10.1016/j.engstruct.2018.12.034 . Calvi, G.M., Sousa, L., Ruggeri, C., 2016. Energy e ffi ciency and seismic resilience: A common approach, In: Multi-Hazard Approaches to Civil Infrastructure Engineering. Springer International Publishing. chapter 9. pp. 165–208. References