Novel Remediation for Buried Pipelines under Ground Deformation: Large-Scale Laboratory Testing and Numerical Modeling

Abstract

A novel mitigation technique is proposed in this paper to effectively improve the safety and integrity of buried pipelines subjected to ground deformation and to mitigate the detrimental effects of ground deformation on the pipe. This technique involves the installation of special geomaterial blocks (SGBs) adjacent to the pipe. The SGB consisting of multiple layers of hollow plastic boxes placed between layers of high-density expanded polystyrene (EPS) geofoam blocks forms a thick sandwich panel structure, which is oriented such that its orthotropic mechanical property allows the pipe to move laterally without developing significant reactions against the soil. A summary of past mitigation techniques and the method proposed in this study are first presented. Large-scale experimental testing used to assess the beneficial effects of the SGB on the pipe response when subjected to lateral and oblique displacements is then presented, followed by a simplified finite element model proposed to numerically simulate the pipe-SGB-soil interaction under lateral soil displacement. The results confirm that the proposed remediation method can significantly reduce the soil-pipe interaction force. Furthermore, the proposed beam-based numerical model that can be used in engineering design predicts well the lateral load-deformation response of the system.