Development and Application of Geobuffer System to Reduce the Impact of Ground Movements on Buried Pipes

Abstract This paper introduces an alternative solution for enhancing the performance of buried pipelines under various scenarios of ground displacements through the installation of Geobuffer elements. Installation of the Geobuffers allows for controlled modification of pipe’s boundary conditions based on the expected ground movement rate and direction. This modification enables the pipe to distribute the applied displacement more effectively, which prevents concentration of stress/strain. The orthotropic properties of the Geobuffer make it flexible in one direction and stiff in the other orthogonal directions. As a result, it can accommodate large pipe movements without developing large reactive forces, while adequately resisting soil and overburden pressure. By using this method, the pipe maximum curvature and axial elongation are reduced significantly which results in lower longitudinal strain ranges and lower risk of subsequent failures. Reduction of the longitudinal strain accumulation rate also increases pipes life span in steady and slow ground movement scenarios (e. g., slope creep); and decreases probability of failure in episodic movement scenarios (e.g., fault slip). This paper reviews the background and development stages of the Geobuffer system and continues with presenting its application on one pipeline crossing an axial/oblique landslide. The installation scope and layout were developed for this site based on the landslide and pipe characteristics and targeted tolerance level for future movements. The key design and development steps for this application are reviewed here, including design inputs, sizing and layout, performance evaluation analysis, installation, and the monitoring system. This paper concludes with a discussion of utilizing the Geobuffer system in the integrity management of pipelines and how it can offer value in certain areas.