Modelling Cathodic Protection Performance of Steel Pipeline under Dynamic Soil Moisture Environment (C2026-00221)

Xingsen Yang, Hao Wang

Cathodic protection (CP) is a widely adopted method for mitigating external corrosion in buried pipelines, and its effectiveness is typically evaluated in practice by whether a fixed potential threshold is met. This approach may be inadequate under real-world conditions, where CP performance is strongly affected by variations in soil moisture content. This study develops a finite element model that integrates soil hydrodynamics, climate-controlled surface boundary conditions, and moisture-dependent electrochemical behavior to simulate the spatiotemporal evolution of cathodic protection effectiveness under realistic environmental condition. Simulation results demonstrate that variations in soil moisture significantly influence the spatial and temporal performance of CP systems, affecting their ability to deliver consistent and effective corrosion prevention under dynamic field conditions. Under seasonal moisture cycles, maintaining a fixed level of CP application of CP application may result in suboptimal performance, leading to localized under- or over-protection. The proposed model offers a robust basis for evaluating CP performance under transient subsurface conditions and can be integrated with sensing techniques such as ground-penetrating radar to support adaptive, data-informed protection strategies for long-term pipeline integrity management.