Integrating tri-phase resilience and intangible benefits in project CBA: A tiered framework for critical infrastructure

Critical-infrastructure project appraisal often undervalues resilience investments because many disruption impacts are non-market in origin yet material for stakeholders. This study proposes the tiered tri?phase resilience valuation framework plus (TRVF+), which integrates three operational resilience dimensions – preparedness, continuity maintenance, and restoration – into a CBA-compatible decision metric. TRVF+ computes normalized indices (PPI, CMI, SRI/SRI_adj) and a composite social stability index (CSSI); monetizes avoided disruption impacts (ADIC) from complaints, trust/satisfaction proxies, and regulatory standing; and propagates parameter uncertainty via Monte Carlo simulation (10,000 runs per case) to estimate a resilience-adjusted benefit–cost ratio (RABCR) and the decision-robustness probability Pr(RABCR>1.0). The framework is demonstrated on four anonymized pilot cases representing increasing data maturity (Tier 1–3). Monetized intangible benefits account for ~15–30% of total benefits on average (up to ~40% within Tier?1 uncertainty bounds). Across cases, baseline BCR values of 0.88–1.15 increase to post?intervention RABCR values of 1.10–1.45, and decision robustness meets or exceeds a moderate acceptance rule (Pr(RABCR>1.0)?0.80; observed range 0.81–0.95). TRVF+ enables auditable valuation of resilience and supports communication of uncertainty in stakeholder consultations and public hearings.