## 4 Analysis of Results  
### Results of Life Cycle Assessments  
Figure 3 illustrates the results of the LCCA for alternatives to retrofit the beam with shear deficiencies. The costs are expressed as present values as of January 2025. Construction costs are the most significant component of the total costs, accounting for an average \begin{table}
\begin{tabular}{l l l l l} \hline
**Dimension** & **Criteria** & \multicolumn{2}{c}{**Indicators**} \\ \hline  & C1 & Construction cost & I1 & Construction cost (USD) \\ \cline{2-5} Economic & C2 & Maintenance and EoL costs & I2 & Preventive maintenance (USD) \\  & C2 & Maintenance and EoL costs & I3 & Maintenance (USD first 10 years) \\  & C2 & I4 & Demplition, classification, and \\  & C3 & Manufacturing and construction & I5 & Ecosystem (Points) \\  & C3 & Manufacturing and construction & I6 & Human health (Points) \\  & C4 & Maintenance and EoL & I7 & Resources (Points) \\ \cline{2-5}  & C5 & Local Community and Society & I11 & Local Community (MRH) \\ Social & C6 & Value Chain Actors and Workers & I12 & Society (MRH) \\  & C7 & Duration of works & I15 & Duration of works/disruption to \\ Functionality & C8 & Architectural impact & I16 & Architectural impact (scale) \\ \hline \end{tabular}
\end{table} 
Table 3: Hierarchical tree of the decision model. of 82% across all alternatives. The CFRP alternative incurs the highest construction costs due to the expensive raw materials. CJ ranks second, mainly due to the high cost of the formwork system required. The STE and STA alternatives have the highest costs in the maintenance stage. This is attributed to the inclusion of two types of preventive maintenance: anti-corrosion paint with fireproofing mortar, which represents a 2.3 times increase compared to the preventive maintenance cost of the CJ alternative. In the EOL phase, the costs are especially significant for the CJ and SCJ alternatives due to the requirements for the pretreatment of concrete waste. The percentages shown in Figure 3 represent the total LCCA values, with the CJ alternative as the benchmark. The SCJ alternative has the lowest total costs, with a 45% reduction, while the CFRP alternative has an increase of 1%. The ReCiPe endpoint approach provides straightforward LCA results for environmental impacts, offering a clear overview of the effects associated with each alternative. Figure 4 highlights the impacts across damage categories: Ecosystems, Human Health, and Resources. The manufacturing phase has the highest impact in all damage categories, with the exception of the STE alternative, which has the highest values for the preventive maintenance stage in the Ecosystems category. In the EoL phase, impacts are substantial for CJ and SCJ. Regarding total impact values measured in points, the Resources category has the highest representation, followed by Human Health and Ecosystems. Among all alternatives, CJ exhibits the highest environmental impact. SCJ ranks second but achieves the most significant reduction in the Resources damage category, with a 21% decrease compared to CJ. Despite requiring higher energy consumption for machinery operations during the manufacturing and application of shotcrete, SCJ benefits from the reduction of structural adhesives, which helps lower its overall environmental impact. STE and STA alternatives offer substantial ecological advantages, particularly in the Human Health category, with reductions of 69% for STE and 79% for STA compared to CJ. Similarly, CFRP presents significant benefits with reductions of 54% in the Ecosystems category, 70% in Human Health, and 56% in Resources compared to CJ. Similarly, the Figure 4d) summarizes the total environmental impacts of the retrofit alternatives. CJ has the highest overall impact, while SCJ achieves a 19% reduction. CFRP shows a 59% decrease, and the lowest environmental impacts are observed for the STE and STA alternatives, with decreases of 62% and 77%, respectively, compared to CJ.