Application of Stay Cable Systems in Large-Span Underground Construction

Abstract

Nowadays, large-span underground structures can only be built at shallow depths or in hard rock since their structural strength is not great enough to bear the overburden pressure of thick overlying soil material. To build large-span structures at greater depths or in a wider range of geotechnical conditions, new technical and technological solutions must be developed. The paper discusses the possibility of using stay cable systems to enhance the load-bearing capacity and service performance of large-span underground structures. To assess the applicability of such stay cable systems for large-span underground construction, a numerical model has been developed and validated. The paper presents the results of the modeling of underground structures (20m to 50m wide) under different pressures and examines how the stress-strain behavior of the load-bearing structural elements depends on the span of the structures, the arrangement and height of pylons, and the number and arrangement of stay cables. It is shown that the use of stay cable systems can significantly improve the load-carrying capacity and performance of both individual structural elements of a large-span underground structure and the structure as a whole. The paper also discusses the possibility of using composite materials for the stay cable systems.