A Data-Driven Strategy for the Structural Health Monitoring of the Machico Cable-Stayed Bridge: A Case Study

The management of aging infrastructure requires a paradigm shift from routine, time-based inspections to data-driven, condition-based assessment. This paper presents a novel and practical framework for this transition through an in-depth case study of the Machico Cable-Stayed Bridge, a modern structure exhibiting accelerated deterioration driven by its aggressive marine environment. The core contribution is a replicable methodology demonstrating how to leverage a unique and disparate set of existing diagnostic data—synthesizing visual inspection reports, non-destructive evaluations, and dynamic in situ measurements—to design a targeted and optimized Structural Health Monitoring (SHM) strategy. The diagnostic analysis reveals critical pathologies, including advanced corrosion and significant discrepancies between design and measured cable forces, a finding that highlights a critical gap in historical performance data. In direct response to an official mandate for continuous monitoring, this paper proposes a multi-level SHM framework where the placement and specifications of each sensor (accelerometers, strain gauges, corrosion sensors) are directly justified by the documented failure modes. This work thus provides a practical roadmap for translating forensic data into a coherent, long-term asset management strategy, bridging the critical gap between diagnostic engineering and proactive infrastructure management.