Field-informed thermo-mechanical modelling of a full-scale energy quay wall

Abstract

Energy quay walls (EQWs) represent an emerging class of energy geostructures that combine geothermal heat exchange with retaining-wall functions along waterways. While their thermal performance has been investigated in several recent studies, their thermo-mechanical (TM) behaviour remains less well documented, particularly under realistic long-term operating conditions. This paper presents a thermo-mechanical analysis of a full-scale EQW installed along the Delftse Schie canal (The Netherlands), combining field temperature and displacement monitoring with calibrated finite-element modelling. A two-dimensional plane-strain model is developed to reconstruct geostatic and thermal initial conditions, simulate short-term geothermal activation phases, and assess the long-term TM response under repeated seasonal operation. Model predictions show that TM-induced wall deformations are small. Short-term TM displacements are on the order of a few tenths of a millimetre, while long-term seasonal activation produces cyclic, predominantly reversible displacements in the millimetric range. No accumulation of plastic strain is predicted over the analysed geothermal operating period. The simulated deformation patterns reflect the combined influence of non-uniform temperature fields, stratigraphic stiffness contrasts, and thermo-elastic deformation of the steel sheet pile, rather than simple uniform thermal expansion or contraction. Overall, the results indicate that thermo-mechanical effects in the investigated EQW are modest and can be reasonably captured by calibrated numerical modelling evaluated against field observations. The study provides a reference framework for incorporating TM considerations into the design and serviceability assessment of EQWs and similar energy geostructures.