Abstract
Flexible pipes are traditionally used for shallow burial depth, say less than 10 m. In recent years, flexible pipes are increasingly used in the difficult terrains for infrastructures, landfills, residential, and industrial developments. Occasionally, the fill height may exceed 20 to 30 m. The existing guidelines do not address the design of flexible pipes under such high fills. In this paper, a general solution for the moment and displacements of a thin-wall ring subject to external earth pressures exerted by the high fills was derived. A finite element procedure was also used to analyze the pipe behavior under high fill. The closed-form solution and finite element results were verified with the measurements obtained from the field under a fill height of 47.1 m. The analytical and finite element results showed good agreement with the measured results. This study revealed that existing design for pipe buried under high fill could be overly conservative and uneconomical. The vertical and lateral earth pressure diagrams for design were revised.
