Stresses and strains in a flexible pipe buried in geosynthetic reinforced soil

Geosynthetics have been used to reinforce soils for over four decades. They can also be used as reinforcement in buried pipe installations to reduce stresses and strains in the pipe, as well as the consequences of pipe explosions. This paper investigates the use of geosynthetic reinforcement to protect a flexible buried pipe from the effects of a localised surcharge on the soil surface. Large scale tests were carried out on an instrumented PVC pipe buried in a rather loose sand. Different types and arrangements of the reinforcement layer were investigated. The results obtained address the relations between stresses on the pipe, pipe strains and pipe deflections and show that the presence of the reinforcement can reduce significantly vertical and horizontal stresses on the pipe as well as pipe deformations. An elastic solution for the prediction of strains at the pipe crown was employed, whose predictions compared well with the experimental results.