Novel Remediation for Buried Pipelines under Ground Deformation: Cross-Sectional Testing and an Analytical Modeling Approach

Abstract

This paper proposes a novel mitigation approach to improve the safety and structural integrity of buried steel transmission pipelines subjected to ground deformation. This method involves altering the boundary condition of buried pipelines with adjacently installed special geomaterial blocks (SGBs) consisting of a set of expanded polystyrene geofoam and polypropylene squared plastic boxes. The proposed SGB allows accommodating ground deformation while significantly reducing the ground-induced forces in the pipe. The mitigation technique is first presented, followed by the experimental test program developed to evaluate the beneficial effects of SGB on the pipe response when subjected to lateral and oblique displacements. Furthermore, a simplified spring-based analytical modeling approach is proposed for predicting the force-displacement response of the pipe–SGB–soil assembly with emphasis on the interaction between the pipe and soil under the new boundary condition. The analytical model is validated using experimental test data. The results of the experimental tests confirm the efficiency of the proposed remediation and feature the relationship between the applied displacement and the force developed in the pipe. Furthermore, it is found that the proposed simplified analytical model can appropriately predict the expected reaction of the pipe equipped with the SGB.