Monitoring Stress/Strain in Buried Pipelines Through the Use of Fiber Bragg Grating Sensors

ECOPETROL S.A. has been working since 2006 in Pipeline Integrity Management Process. In that process, the threat related to climate and external forces play an important role, because of the vulnerability of ECOPETROL pipelines to this threat, not only by the geomorphology of Colombia, but also because of the strong impact of climate phenomenon such as “La Niña”, that consists in an unusual quantity of rain precipitation, represented in the increasing of slopes instability that affects the rights of way. Due to these events and the evolution of optical strain sensors monitoring technology, ECOPETROL has introduced an instrumentation pipeline program for monitoring the strain and advanced in the understanding of the behavior of pipelines. This paper describes the technology selected, the criteria used to select the monitoring sites and the thresholds stress/strain. The results of monitoring are discussed for a particular case.

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Horizontal Movement of Fast Ice in the North Water Area

Journal of Glaciology ◽

10.1017/s002214300002949x ◽

1977 ◽

Vol 19 (81) ◽

pp. 547-554 ◽

Cited By ~ 13

Author(s):

Hajime Ito ◽

Fritz Müller

Keyword(s):

Sea Ice ◽

Water Area ◽

Physical Characteristics ◽

Stress Strain ◽

Horizontal Movement ◽

The North ◽

North Water ◽

Fast Ice ◽

External Forces

AbstractThe understanding of the horizontal movement of fast ice is important for applied sea-ice mechanics. A case study, carried out in conjunction with a polynya known as North Water, is presented in this paper. The displacements of the fast-ire arches which separate the polynya from the surrounding ice-covered sea, were measured and found to be small. It is, therefore, confirmed that these arches prevent the influx of large quantities of sea ice into the polynya. The results are then explained in terms of the external forces (wind and current), the stress- strain situations and some physical characteristics (temperature and thickness) which were measured simultaneously.

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Wide-range linear viscoelastic hydrogels with high mechanical properties and their applications in quantifiable stress-strain sensors

Chemical Engineering Journal ◽

10.1016/j.cej.2020.125697 ◽

2020 ◽

Vol 399 ◽

pp. 125697 ◽

Cited By ~ 3

Author(s):

Changshu Ma ◽

Yi Wang ◽

Zuming Jiang ◽

Zhenxing Cao ◽

Huiting Yu ◽

...

Keyword(s):

Mechanical Properties ◽

Strain Sensors ◽

Stress Strain ◽

Wide Range ◽

Linear Viscoelastic

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Evaluation of Strain Transition Properties between Cast-In Fibre Bragg Gratings and Cast Aluminium during Uniaxial Straining

Sensors ◽

10.3390/s20216276 ◽

2020 ◽

Vol 20 (21) ◽

pp. 6276

Author(s):

Florian Heilmeier ◽

Robert Koos ◽

Michael Singer ◽

Constantin Bauer ◽

Peter Hornberger ◽

...

Keyword(s):

Bragg Gratings ◽

Tensile Specimen ◽

Strain Sensors ◽

Fe Model ◽

Plastic Strains ◽

Closing The Gap ◽

Optical Strain ◽

Structural Parts ◽

Fibre Bragg Gratings

Current testing methods are capable of measuring strain near the surface on structural parts, for example by using strain gauges. However, stress peaks often occur within the material and can only be approximated. An alternative strain measurement incorporates fibre-optical strain sensors (Fiber Bragg Gratings, FBG) which are able to determine strains within the material. The principle has already been verified by using embedded FBGs in tensile specimens. The transition area between fibre and aluminium, however, is not yet properly investigated. Therefore, strains in tensile specimens containing FBGs were measured by neutron diffraction in gauge volumes of two different sizes around the Bragg grating. As a result, it is possible to identify and decouple elastic and plastic strains affecting the FBGs and to transfer the findings into a fully descriptive FE-model of the strain transition area.We thus accomplished closing the gap between the external load and internal straining obtained from cast-in FBG and generating valuable information about the mechanisms within the strain transition area.It was found that the porosity within the casting has a significant impact on the stiffness of the tensile specimen, the generation of excess microscopic tensions and thus the formation of permanent plastic strains, which are well recognized by the FBG. The knowledge that FBG as internal strain sensors function just as well as common external strain sensors will now allow for the application of FBG in actual structural parts and measurements under real load conditions. In the future, applications for long-term monitoring of cast parts will also be enabled and are currently under development.

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Vulnerability of Buried Pipelines to Landslides

Volume 2: Pipeline Safety Management Systems; Project Management, Design, Construction and Environmental Issues; Strain Based Design; Risk and Reliability; Northern Offshore and Production Pipelines ◽

10.1115/ipc2016-64071 ◽

2016 ◽

Author(s):

Gerald Ferris ◽

Sarah Newton ◽

Michael Porter

Keyword(s):

Ground Movement ◽

Buried Pipelines ◽

Large Numbers ◽

Vulnerability Model ◽

Cause Of Failure ◽

Integrity Management ◽

Pipeline Failure ◽

As Stress ◽

Pipeline Failures ◽

Landslide Movement

The movement of a mass of rock, debris or earth down a slope is a landslide, which in the pipeline industry is often referred to as ground movement. Landslides continue to cause pipeline failures throughout the industry, sometimes as the singular cause of failure and in others cases as a contributing factor to failures (such as stress corrosion cracking on slopes). Landslides can originate on slopes above a pipeline and cause impact loads; they can originate below a pipeline and cause unintended spans; and they can encompass the ground crossed by a pipeline, which can lead to high compressive (or tensile) strains and pipeline buckling. This paper focuses on the latter scenario. Similar to the approach recently outlined for watercourses [1], the term ‘vulnerability’ refers to the conditional probability of pipeline failure given that landslide movement spatially impacts a pipeline. This paper presents the development of a statistical and judgment-based vulnerability model for pipeline crossings of slopes that are subject to landslides that can be used to rank the relative importance of slopes at a screening level of assessment. The model is based on case histories where this type of landslide scenario caused pipeline failures (defined as holes, leaks and ruptures), or buckling of pipelines that resulted in the need for immediate repairs. Vulnerability has two main uses: on its own to help prioritize large numbers of slope crossings for further investigation; and, once combined with estimates of the probability of landslide movement, to provide a probability of pipeline failure estimate that can be used to guide integrity management programs.

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Proactive Approaches to Geohazard Management

ASME 2017 International Pipeline Geotechnical Conference ◽

10.1115/ipg2017-2537 ◽

2017 ◽

Author(s):

S. Ruik Beyhaut

Keyword(s):

Technological Development ◽

Seismic Intensity ◽

Management Program ◽

Slope Instability ◽

Mitigation Measures ◽

Critical Element ◽

Bending Strain ◽

Actual Movement ◽

Integrity Management ◽

External Forces

To control the threats from external forces, pipeline owners and operators require detailed information about their pipeline infrastructure and the environment surrounding that infrastructure. The contribution from geographic data is recognized as an increasingly important part of a complete integrity management program, particularly for the identification of geohazards. This is because geohazards are generally characterized by high spatial variability, are complex and difficult to quantify but may result in catastrophic failure of pipelines. In recent years we have seen widespread technological development surrounding the processes to capture information in order to deliver quantitative inputs for pipeline engineers, risk & geotechnical experts. International codes & best practices (e.g. AS 2885.1-2012) state that “Environmental impact assessment is not simply a vehicle to obtain regulatory approval, it is a critical element of the planning for design, construction and operation of the pipeline.” Furthermore, geohazards frequently develop during the service life of pipelines. Consequently, regulators recommend that assessments are conducted on an ongoing basis to identify all potential threats and implement mitigation measures. A process has been developed to create efficient and economical solutions for monitoring and assessing the significance of pipeline bending strain and whether actual movement has taken place. This process can make use of a variety of inputs including slope gradient, climate, groundwater conditions, slope instability, seismic intensity, and environmental impacts, and can provide important information in the determination of potential mitigations. This paper will review the benefits which can be gained from the implementation of integrated approaches to inform geohazard management.

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Stress-Strain-Analysis of Grapevine Pruning with Powered and Non-Powered Hand Tools

Proceedings of the Human Factors and Ergonomics Society Annual Meeting ◽

10.1177/154193120004402238 ◽

2000 ◽

Vol 44 (22) ◽

pp. 639-642 ◽

Cited By ~ 1

Author(s):

Jurij Wakula ◽

Thomas Beckmann ◽

Michael Hett ◽

Kurt Landau

Keyword(s):

Strain Analysis ◽

Stress Factors ◽

Climate Condition ◽

Hand Tools ◽

Stress Strain ◽

Repetitive Movements ◽

Power Tools ◽

Power Hand Tools ◽

External Forces

Non-power and power cutting hand tools are mainly used every day in vineyards for grapevines pruning during 5 months (November - March). The grapevines pruning with the help of non-power tools is very stressful for wine growers. Repetitive movements combined with external forces in finger-hand-wrist-system, extreme positions in arm-shoulder-system, climate condition are some of the stress factors. Grapevines pruning with 5 manual prunes produced by 3 different manufacture and 2 power hand tools (electrically and pneumatically) were analysed. The results reveal that grapevines pruning with pneumatic and electric prunes is up to 30% more effective (according to productivity) than cutting with non-powered hand tools. At the same time is grapevines cutting with power tools more stressful as with non-powered one.

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