This report provides a complete background on the topic of “Increasing Resilience of Earth Structures to Natural Hazards” assigned to WG1 of PIARC TC 4.3 as part of the 2020-2023 Work Program. This topic has been developed as part of the 2020-2023 Work Cycle and is complemented by two additional documents for this topic: a Case Studies Report and a Literature Review Report.

The production of this report was carried out in multiple phases. The first phase involved a cursory review and selection of relevant documents from the literature that address, directly or indirectly, the concept of resilience. The selected documents address the concept of resilience in various ways, from the most general meaning of the concept to its specific application in road infrastructure.

In a second phase, relevant case studies related to resilience in earth structures, collected among members of PIARC TC 4.3, have been analyzed using a common framework, to identify which are the most common hazards that are currently affecting earth structures, what is the most common damage they suffer due to these impacts and which are the most common measures that are applied to repair or to adapt these assets.

As a result of this WG1 final review, it was concluded that resilience is a concept that can be applied to earth structures taking into account the whole life cycle of the assets, starting from the inception (design phase) up to construction and management. Specific directions and recommendations have been identified and their application was discussed together with relevant examples taken from cases.

In order to serve its function as background and reference for the resilience concept as applied to earth structures, recommendations and conclusions have been provided in Chapters 10 and 11 of the document.