L51515 Monitoring and Intervention on Pipelines in Mining Subsidence Areas

Longwall mining can constitute a threat to the integrity of a pipeline by way of surface subsidence and soil strains. The subsidence and soil strain phenomena associated with longwall mining have been studied in detail both in the United Kingdom and the United States. Empirically-based methods are available to predict both subsidence and surface soil strains. These methods can be used to estimate the possible effects of subsidence on buried pipelines.

The objectives of this study were to review the effects of longwall mining subsidence on pipelines and to develop concepts for preserving the integrity of pipelines affected by such subsidence. Presented in this report is a discussion of the subsidence phenomena and terminology, calculations for hypothetical settlement cases, the appropriate monitoring and intervention responses with respect to any possible effects on a pipeline, and examples of actual pipeline monitoring experience. A suitable strain monitoring technique is described in this report.