PSI - Issue 55

Poliana Bellei et al. / Procedia Structural Integrity 55 (2024) 96–102

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Poliana Bellei et al. / Structural Integrity Procedia 00 (2019) 000 – 000

if the calcination process is indeed necessary. Nevertheless, considering that all mortars have similar characteristics, the 24% NHL-COSP mortar, with 24% substitution of natural hydraulic lime with calcined oyster shell powder, stands out for its negative environmental impacts (Fig.3). 4. Conclusions This work found to identify the environmental impacts of recovering traditional construction techniques in coastal regions by incorporating oyster shells into mortar to achieve the blue circular economy. The LCA of three different types of mortars was analyzed in terms of GWP and compared with each other and with a standard construction technique. There are previous records of the use of oyster shell in coastal regions in ancient times. The shell was used to replace lime due to its scarcity. Nowadays these construction techniques are little used by the population. The accumulation of shells generated by oyster mortality in the aquaculture industry, and the disposal of shells in common waste after consumption by the food industry are problems that can be minimized through the recovery of traditional construction techniques. Firstly, the mortar produced with 24% replacement of natural hydraulic lime by oyster shell powder (obtained by a mechanical process) was the solution with the lowest environmental impact generated. The solution replacing 30% natural aggregate by oyster shell aggregate was the second one with the lowest environmental impact. The solution (24% NHL-COSP) with shell calcination (thermal process) demonstrated the greatest environmental impacts. Thus, it is essential to assess the equilibrium between the performance enhancements and the potential negative environmental impacts. Concrete and mortar are used worldwide in civil construction due to their ease of working, high strength, and wide availability of their components. On the other hand, high consumption raises concerns about the scarcity of raw natural aggregates, and it is of great importance to seek alternatives to mitigate these negative impacts, such as the replacement of natural materials by oyster shell-based products as a binder or aggregate. With this development, the cluster of activities associated with bivalves grows, extending in value to production activities, new distribution circuits and waste collection, generating employment and economic value, also with an impact on the social dimension. Finally, mention should be made of valuing the environmental dimension in which waste from consumption is reduced, which is thus sustainably incorporated into the territories where it is developed. The recovery of marine waste thus represents a good example of a blue circular economy. Acknowledgements The author is grateful for the Foundation for Science and Technology (UI/BD/151151/2021) from the research unit CERIS (UIDB/04625/2020), and the EEA Grants support through funding SHELLTER project (FBR_OC2_30). References Bellei, P., Torres, I., Solstad, R., Flore-Colen, I., 2023. Potential Use of Oyster Shell Waste in the Composition of Construction Composites: A Review. Buildings, 13, 1546. https://doi.org/10.3390/buildings13061546. Chandra, S., 2003. History of Architecture and Ancient Building Materials in India - Single Volume. Tbi - India. [Online] Available at: https://archive.org/details/Aravindctmt_AncientBuildingMaterialsInIndia/page/109/mode/2up. DGRM, 2021. Direção Geral de Recursos Naturais, Segurança e Serviços Marítimos - Estatísticas da Pesca 2021. European Commission, 2023. European Platform on Life Cycle Assessment (LCA) - Environment. Eikeset, A. M., Davíðsdóttir, A. B., Klinger, D. H., Levin, S. A., Rovenskaya, E., Stenseth, N. C., 2018. What is blue growth? The semantics of “Sustainable Development” of marine environments. Marine Policy . EPA, 2023. United States Environmental Protection Agency. Design for the Environment Life-Cycle Assessments.

FAO, 2022. The State of World Fisheries and Aquaculture. Towards Blue Transformation. Rome, FAO. Félix, F., Hinzmann, M., Vaz-Pires, P., 2018. Manual de boas práticas na ostreicultura em Portugal.

Guedes, P., 2018. Learning from the ‘other’: Early modern emulation and tLearning from the ‘other’: early modern emulation and trans -imperial exchange of ‘native’ building technologies – in: Wouters, Van de Voorde, Bertels et al. Building Knowledge, Constructing Histories. Guimarães, J. E., 2002. A Cal: Fundamentos e Aplicações na Engenharia Civil. In:Pini Ltda, 2ª (Ed.). São Paulo.