What is the function of structural health monitoring (SHM) in bridge management and what sensors are commonly used?

• A. SHM provides ongoing data on health and condition to inform maintenance; common sensors include accelerometers, strain gauges, displacement sensors, corrosion probes, and corrosion monitoring devices.
• B. SHM provides no maintenance guidance.
• C. SHM only monitors temperature sensors.
• D. SHM uses visual inspection only.

Answer: (A)

Structural health monitoring provides ongoing, quantitative information about a bridge’s health so maintenance decisions can be planned and risks managed. It supports life-cycle management by enabling condition-based maintenance, early damage detection, trend analysis, and assessment of performance under traffic and environmental influences. Common sensors used include accelerometers to capture dynamic behavior and vibrations, strain gauges to measure internal stresses, displacement sensors to track deflections and geometry changes, and corrosion probes or corrosion monitoring devices to track deterioration of reinforcing steel and protective coatings. The data from these sensors are analyzed to detect anomalies, estimate remaining life, and guide inspections or repairs before problems become critical. Temperature-only sensing or relying on visual inspections alone cannot provide the full, continuous picture of structural integrity and damage progression.