From Durability to Circularity in Textile-Reinforced Mortar: Residual Performance, Degradation Pathways, and End-of-Life Decisions

Circular recovery decisions for aged strengthening systems require evidence that distinguishes loss of installed function from exhaustion of constituent value. Conventional durability studies rarely translate residual mechanical states into end-of-life decision support. This study develops an uncertainty-aware, multi-scale assessment for textile-reinforced mortar (TRM) based on three observed residual states: matrix retention (R_m), local pull-out/interface-related retention (R_i), and TRM-to-substrate/system-bond retention (R_b). AR-glass- and basalt-reinforced lime-based TRM systems were evaluated under dry reference, distilled-water, saline, alkaline, and acidic conditions after 1000, 3000, and 5000 h of exposure. Residual states were normalized to time-matched dry references, while 10,000 specimen-level bootstrap resamples quantified uncertainty. Cross-scale contrasts were used to identify degradation localization, and scenario thresholds of 0.60, 0.70, and 0.80 supported five performance-based end-of-life pathways. Among 24 non-reference conditions, 13 showed statistically supported localized or distributed degradation, whereas 11 remained uncertainty-dominated. At R_crit=0.70, 12 conditions were classified as continued-service candidates, two as repair/rebounding candidates, seven as recovery-assessment candidates, none as material recycling/downcycling candidates, and three as requiring further inspection. At 5000 h, basalt-reinforced systems exposed to distilled water, alkaline, and acidic environments consistently exhibited a recovery-assessment pattern in which system-level functionality deteriorated while the observed lower-scale states remained comparatively preserved. No tested condition showed robust evidence of simultaneous broad performance exhaustion across all three observed scales. Sensitivity analyses confirmed that alternative matrix definitions, baseline selection, and rupture handling did not alter modal pathway assignments, whereas stricter uncertainty treatment redirected several cases to further inspection. These results show that system-level functional deterioration need not coincide with exhaustion of observed lower-scale material states, supporting condition-based end-of-life screening before repair, recovery, or recycling decisions are made. The proposed pathways identify candidates for subsequent action rather than experimentally verifying constituent reuse or recyclability.