Low‐settlement construction of crossings through embankments

Abstract

Adapting existing assets will pose an increasingly significant challenge in the future in order to ensure sustainable operation, long‐term maintenance, and the necessary expansion or adaptation of the infrastructure to new requirements and conditions. In the case of transportation routes, their availability must be taken into account above all, which for rail routes often represents one of the decisive constraints due to a lack of detour options. In addition to construction activities along open stretches or in tunnel and cutting areas, embankment structures and fill sections are often part of maintenance projects. Among other things, it is often necessary here to integrate crossings into embankment structures, for example, to reduce above‐ground crossings or to replace existing crossings with new structures. In addition to traditional methods involving the excavation of a construction pit and the erection of the structure followed by backfilling, trenchless pipeline construction methods can be used here. The article focuses on the jacking method. In this process, culvert sections prefabricated outside the dam are pressed into the dam body using jacking equipment, and the resulting spoil is simultaneously removed from inside the culvert section. This approach makes it possible to construct a crossing with minimal impact on the embankment body (minimal settlement of the crest) with minimal or no disruption of the underpassed line (e.g., slow‐speed zones).