Mechanical Behavior of Large Flexible Pipe Buried in Shallow Cover

Field Performance of Pipeline with Uplift Enhancement by Use of Geogrids

Abstract

The paper presents the results of field tests that were conducted to reveal the mechanical performance of large flexible pipe buried in shallow cover with enhancement of the uplift capacity of buried pipelines by the use of geogrids.
Twin type flexible pipes, whose diameter was 2400mm, were installed in the field with 1.5m cover. The mechanisms involved in the uplift process under increasing ground water level and the behavior of pipe during construction were discussed. After measurement for the performance of pipe, about 1 year duration, the results indicate that the deflection of pipe is less than 1% of diameter and the force onto the geogrid is about 10% for the ultimate strength of that. The results of field test reveal that the pipe with geogrid protection is restrained its deflection during the installation of pipe, and that the uplift resistance of buried pipeline can be increased significantly by the incorporation of geogrids.