Geohazards, such as landslides or settlement, are a major threat to pipelines because the loading can be challenging to identify or predict. Even once they are properly identified, managing the threat posed by any given geohazard is difficult. Visual movement at the surface does not necessarily mean that substantial loads are applied to the pipeline below. In many cases, surface movement may leave the pipeline unaffected, while in other cases, the movement may have significant impacts on the pipeline. Visual observations can be obscured by vegetation or occur over a sufficient duration so that small changes are not evident in periodic inspections. New construction for roads or housing developments create additional surface loads that can result in subsidence. The consequences of geohazard loading can include unexpected failure by tensile fracture or compressive buckling.

Fortunately, in-line inspection technology using an inertial measurement unit (IMU) allows operators to identify the presence of external loads on their pipelines. Historically, operators have used IMU technology for line location and improved feature location during excavations. However, the data collected from IMU technology has value beyond simply locating ILI features – a value that is often underutilized in the pipeline industry. IMU data essentially measures pipeline curvature, which is directly proportional to the amount of bending strain in the pipeline. Engineering analysis of this dataset permits as-built construction strains to be differentiated from locations where the pipeline has been subjected to external loads. This valuable information permits the early identification of loads that are imposed on the pipeline from external sources, helping operators to evaluate and monitor or mitigate the threat as part of a geohazard management process. With repeat IMU assessments, even better information can be provided to the client – namely whether the feature is active and the rate of loading on the pipeline.

In this webinar, we will describe the key role that bending strain measurement plays in the evaluation and management of pipeline integrity. This webinar will cover the basics of IMU inspection to define strains in the pipeline and explain how repeat inspection can demonstrate whether the pipeline has experienced movement under the action of external loads.

A geohazard management process based on IMU data will be presented. This process will prioritize the threat presented by each bending strain location. In addition, the discussion will include sample actions to address the varying magnitudes of the geohazard threats and illustrate how the process provides a clear framework for making decisions in response to geohazard loads.

Please join this free webinar to learn about the key role of inertial measurement unit (IMU) data from in-line inspections in identifying, evaluating and controlling geohazard loading on pipelines.

The webinar will be presented live by our experts on July 11, 2019 at 8 AM (London Time) and 5 PM (London Time).

Presented By

Rhett Dotson, PE
Principal Engineer

Rhett Dotson has worked as a consultant in the oil and gas industry for 13 years. Rhett has developed technical expertise in analysis and testing for structural components and pipeline systems. His work with offshore systems has included strength and fatigue analysis performed on topsides and subsea components. His work with pipeline systems has included assessment and engineering support for anomalies such as dents and wrinklebends in vintage pipeline systems as well as accident investigations due to third-party damage in both onshore and offshore pipeline systems. Rhett has also served as an expert witness for a pipeline operator involving settlement-related issues. Recent structural work has included the analysis and remediation of damaged natural gas pipelines and the determination of in-place pipeline strains based on survey data and finite element calculations.


Andy Young
Principal Geohazards Engineer

Andy Young is a principal geohazards engineer in ROSEN’s integrity solutions team. He has over 25 years of experience in the structural evaluation of pipelines from the effects of ground movement and external loading, including the development of in-line inspection data to enhance the evaluation of geohazards. Andy participated in the ISO committee for the development of ISO 20074 on geological risk management for onshore pipelines and developed a module on geohazards and pipelines for the MSc in Pipeline Integrity Management at Northumbria University.



  • Understand how pipeline bending strains are measured using IMU technology during in-line inspection
  • Appreciate the benefits of pipe movement detection from repeat IMU inspection.
  • Learn how the significance of measured bending strains can be established from the strain magnitude and cause of the strain.
  • Gain awareness of how geohazards affecting pipelines can be managed through a clear and systematic process that is built around available IMU inspection data.


This webinar is aimed at professionals with responsibilities in pipeline integrity management.