Existing Systems for Earth-Retaining Structures Monitoring, New Approaches and Future Trends—A Survey

Earth-retaining Structures are engineered systems designed to hold back soil, rock, or other materials and prevent landslides or the collapse of earth onto roadways. These structures are essential for stabilizing slopes and supporting excavations. They play an important role, especially in transportation infrastructure systems. One of the biggest challenges the asset holders are facing with, is the maintenance of these important as-sets. Several techniques have been used recently to monitor the health level of these geotechnical systems. Although there are some works reviewing these structural health monitoring techniques for civil structures, none of them specifically focused on earth-retaining structures which leads to an overall lack of knowledge in this field. Therefore, this survey aims to conduct a comprehensive review of health monitoring methods that are being used for the assessment of these important geotechnical assets to highlight the current state of research, identify gaps and limitations, and suggest fu-ture directions. In particular, this paper outlines the importance of timely maintenance for earth-retaining structures, presents the types of structural health monitoring meth-ods used for predictive or preventive maintenance of these assets, and finally, identi-fies the challenges and new solutions to help with a more efficient assessment and monitoring of these assets.