Integrated Measurements and Digital Image Correlation for Performance Assessment of a Gabion Foundation Under Compressive Loading

This study investigates the contribution of measurements and Digital Image Correlation (DIC) to describe the performance of a gabion foundation under vertical compressive loading. The investigated system, named the Ledrosteel Foundation (LSF), is a novel prefabricated shallow foundation designed for lightweight one–or two-storey timber buildings. It consists of a kit made of a steel weldmesh gabion filled with stone aggregate and closed with a special lid that integrates a reinforced concrete beam and a hinge for the connection to the superstructure. An extensive experimental campaign was carried out to investigate the mechanical response of the LSF under vertical loading, using different types of limestone aggregates. To obtain detailed information for the calibration and validation of numerical models, conventional measurements (load cells and displacement transducers) were integrated with full-field DIC. While displacement transducers captured the movements of selected points on the weldmesh gabion and top beam, DIC enabled the observation of the displacement field of the stone aggregate. This paper presents the results obtained from two kits filled with aggregates of the same lithology and grain size distribution, but differing in porosity. DIC analysis revealed that aggregate downward displacement increases with porosity; however, the majority of this displacement is primarily due to the compressibility of the hooks connecting the side panels of the gabion to its base.