RISK-BASED RETROFITTING AND STRUCTURAL REFURBISHMENT OF AGEING INFRASTRUCTURE IN SAUDI ARABIA: AN SBC-COMPLIANT FRAMEWORK FOR LONG-TERM RESILIENCE

Ageing infrastructure in Saudi Arabia faces interacting threats from material deterioration, altered occupancy, extreme environmental exposure and uncertain construction records. Conventional refurbishment decisions often respond to observable defects or available budgets without explicitly connecting structural risk, code applicability and continued service. This critical review synthesises 30 DOI-traceable studies published between 2020 and 2025, together with the published scope of the Saudi Building Code, to develop a staged decision framework for existing buildings and associated civil assets. Its aim is to establish a defensible relationship between evidence quality, consequence-based prioritisation, retrofit mechanisms and verified in-service performance. The synthesis distinguishes condition from vulnerability, life safety from functional recovery, and repair from structural strengthening. A six-gate pathway is proposed covering asset classification, diagnosis, hazard-sensitive assessment, intervention selection, approval and longitudinal monitoring. Comparative appraisal shows that no retrofit technique can be chosen by nominal strength gain alone: deformation compatibility, foundations, constructability, environmental durability and nonstructural functionality control the outcome.