This paper investigates an experimental study on reducing stress acting on buried flexible pipes by using expanded polystyrene (EPS) geofoam techniques. An experimental model was carried out with dimensions depending on pipe diameter (D) and location, the used fill cover material was from sand and EPS blocks either embankment form, or within sand backfill as embedded layer. The pipe flexible is un-plasticized polyvinyl chloride (UPVC). A series of experiments have been carried out by using static surface loading on rectangular steel plate,where the load is distributed over the backfill. The behavior of sand backfill around the pipe was observed, and the displacement and strains of the pipe were measured.
The experimental results showed that the embedded layer of EPS geofoam block embedded in sand for different techniques reduced the deformation of flexible buried pipe, with high efficiency and low coast compared with EPS geofoam only. The results reveal that, the most effective methods thatcanreduce the stress on buried flexible pipe with low cost were EPS encasement block with head void method, and EPS block embraces the upper part of pipe method.