Threat Awareness: Geohazards, Bending Strain and Line Movement

Is movement straining your pipelines? Join our Integrity Engineering Solutions experts, Jacques Nicol and David Sunwall, as they dig into line movement and bending strain.

Discover how geohazards can affect pipelines and how TDW experts assess strain and measure curvature growth. The insights provided by these assessments help operators uphold the safety of their pipelines and mitigate the risks associated with line movement events.


Today, we're going to talk about geo hazards, bending strain, and line movement. The world is a dynamic place. The ground is constantly shifting and moving. Geohazards don't discriminate.

Terrain really isn't the best indicator of whether or not a pipeline is at risk. Whether it's in a mountainous region or in the flattest of prairies, geohazards are still a concern. Regulators are keenly aware of this threat and have released several advisory bulletins to help operators manage this concern.

What are geohazards?

Geohazards are essentially when a force, particularly a force of nature causes the earth to move.

When the pipe has been moved, it causes the material on the pipe to either stretch or compress. This stretching and compressing of the pipe material is what we call strain. Bending strain in and of itself can be a major threat to your pipeline, but even if there is only a moderate amount of strain in your line and you combine it with other moderate threats, it can then become a critical threat to your pipeline. A good example of that is circumferential stress corrosion cracking, where you have the threat of bending strain combined with the threat of corrosion. When you bring those two threats together, they can create cracking in your pipeline.

When should operators be concerned about geohazards?

Perhaps after a major event has occurred, maybe you have a pipeline that was located nearby an earthquake or located in an area where there's considerable amount of flooding. Whatever it might be, if you experience a major event on your line, you might want to consider if that major event introduced strain into your even if there hasn't been a major event in areas that are particularly prone to geohazards, there are small natural things that can be happening or going on which might introduce enough strain into your pipe tool to where it fails, even if it's in areas that may not be mountainous or or have steep slopes. There's water and rain that occurs everywhere. And so it's possible, heavy rainfall or or even normal rainfall might cause the soil conditions to change where your pipe is located and cause your pipe to move.

How can operators monitor the effects of geohazards?

We have a two different tools to address geohazards that might affect operators' pipelines, bending strain analysis and line movement analysis. With our mapping technology, we're able to calculate it very precisely what the position of the pipe is. And then based off of that position, we can then calculate the strain that is in your pipeline.

Line movement's a little bit different, a little more advanced because you need to have run our mapping technology on two different inspections. We compare them, and then we can see if the strain in the pipeline has changed over time. And if we see a significant amount of change, that potentially indicates that pipe has moved. And that really helps us prioritize which features you might want to either go dig or monitor.


We can't control the weather or how the Earth is moving, but we do have the technology to help you manage those threats effectively. If you have any questions about bending strain or line movement, the Integrity Engineering Solutions (IES) team is always here to help.