Field Observations of Tidal- and Thermal-Induced Deformations and Anchor Forces in Quay Walls

Abstract This case study investigates the mechanical and thermal response of anchored quay walls in the Port of Rotterdam through continuous field monitoring. Three structurally distinct combined quay walls, consisting of steel tubular piles with intermediate sheet piles, were examined. Water level, temperature, lateral wall displacement and anchor forces were measured using advanced instrumentation, including optical fiber sensors for anchor forces and shape accelerometer array/field (SAAF) for horizontal displacements. The results show that daily lateral wall displacement fluctuations of approximately 1.5 mm (about 10% of initial displacement) are primarily driven by tidal water-level variations. Seasonal temperature changes cause anchor forces to vary by approximately 60% of the mean, with measured forces mobilizing 20%–60% of design capacity. Temperature measurements indicate that sea-water temperature does not change significantly with depth at any given time, whereas seasonal variations in ground temperature are confined to the upper 8 m. The presented field data provide a valuable benchmark for validating coupled thermomechanical numerical models and guiding the assessment of temperature and tidal-induced deformations and anchor forces in combined quay walls.