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Document type: Part of book or chapter of book
 
Document type: Part of book or chapter of book
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== Error ==
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==2. Numerical modeling==
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In this study, an X80 grade steel pipeline with corrosion defect is modeled. According to the previous analysis, the local stress state of buried corrosion defective pipelines is complicated under the action of unreasonable ground overload. Meanwhile, the focus of this paper is to conduct a safety assessment of buried corrosion defective pipelines under given conditions. Generally, the shape of corrosion defects is irregular. To quantify the shape of corrosion defects, it is necessary to reasonably simplify the model corrosion defects to apply the results to various geometric shapes [19-20]. In many industry standard specifications such as DNV and modified B31G, the maximum corrosion depth (<math display="inline">d</math>
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), width (<math display="inline">W</math>) and length (<math display="inline">L</math>) are used to describe the pipeline corrosion defects. If the defect depth profile is relatively smooth and does not present multiple major peaks in depth, a corrosion defect can be considered as a regular shape [20]. The shape of the corrosion defect of buried pipelines is simplified as a rectangular volume defects and rounded the corners in this paper, as shown in [[#img-1|Figure 1]], which is a common used method in literature [13,17,21].
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<div id='img-1'></div>
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{| style="text-align: center; border: 1px solid #BBB; margin: 1em auto; width: auto;max-width: auto;"
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|style="padding:10px;"| [[Image:Draft_Zheng_851632191-image1.png|426px]]
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|- style="text-align: center; font-size: 75%;"
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| colspan="1" style="padding:10px;"| '''Figure 1'''. Schematic diagram of corrosion defect pipeline
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Numerical analysis of the buried pipeline under the ground loads is conducted by using the FE software ABAQUS6.14. The diameter of the pipeline is 0.66m, and the wall thickness is 8mm. The length of soil along the axial is selected 30 times the pipe diameter, and the height and width are 9 times and 15 times the pipe diameter, respectively, according to the previously published article [1]. Therefore, the whole size of the soil is <math display="inline">20{\rm m}\times 10{\rm m}\times 6{\rm m}</math>, and the buried depth is 1m. Considering that the model and boundary conditions have obvious symmetry, a quarter model is used for calculation, in order to improve the calculation efficiency. The FE model of buried corrosion defect pipeline under ground overload is shown in [[#img-2|Figure 2]]. The equivalent pressure is used to describe the ground overload, and the ground overload directly acts on the soil surface above the corrosion defect pipeline, as shown in [[#img-2|Figures 2]](a) and (c). The pipeline corrosion defect is simplified as a rectangle with rounded corners, and the detailed local shape is shown in [[#img-2|Figure 2]](d).
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The bottom boundary conditions of the model are fixed constraints, and the symmetry constraint is used on the symmetry plane (i.e. the XY plane and the ZY plane). The upper surface of the model is free, and the normal displacement of the outer end faces is restricted to prevent the soil from collapsing. The contact pair algorithm is used to simulate the interface between the outer surface of the pipe and the surrounding soil. And set the friction coefficient as 0.4 [22]. The contact algorithm is widely accepted to simulate the nonlinear behavior of pipe-soil contact, and it can truly simulate the contact force of underground pipeline and soil [2,8].
  
 
== Test ==
 
== Test ==

Revision as of 09:38, 14 May 2021

Abstract

eer-reviewed\nThis chapter examines the importance of “where” mobile work/life practices\noccur. By discussing excerpts of data collected through in-depth interviews\nwith mobile professionals, we focus on the importance of place for mobility, and\nhighlight the social character of place and the intrinsically social motivations of\nworkers when making decisions regarding where to move. In order to show how\nthe experience of mobility is grounded within place as a socially significant construct,\nwe concentrate on three analytical themes: place as an essential component\nof social/collaborative work, place as expressive of organizational needs and characteristics,\nand place as facilitating a blending of work/life strategies and relationships.\nACCEPTED\nPeer reviewed

Document type: Part of book or chapter of book

Error

2. Numerical modeling

In this study, an X80 grade steel pipeline with corrosion defect is modeled. According to the previous analysis, the local stress state of buried corrosion defective pipelines is complicated under the action of unreasonable ground overload. Meanwhile, the focus of this paper is to conduct a safety assessment of buried corrosion defective pipelines under given conditions. Generally, the shape of corrosion defects is irregular. To quantify the shape of corrosion defects, it is necessary to reasonably simplify the model corrosion defects to apply the results to various geometric shapes [19-20]. In many industry standard specifications such as DNV and modified B31G, the maximum corrosion depth (Failed to parse (MathML with SVG or PNG fallback (recommended for modern browsers and accessibility tools): Invalid response ("Math extension cannot connect to Restbase.") from server "https://test.scipedia.com:8081/localhost/v1/":): {\textstyle d}

), width (Failed to parse (MathML with SVG or PNG fallback (recommended for modern browsers and accessibility tools): Invalid response ("Math extension cannot connect to Restbase.") from server "https://test.scipedia.com:8081/localhost/v1/":): {\textstyle W} ) and length (Failed to parse (MathML with SVG or PNG fallback (recommended for modern browsers and accessibility tools): Invalid response ("Math extension cannot connect to Restbase.") from server "https://test.scipedia.com:8081/localhost/v1/":): {\textstyle L} ) are used to describe the pipeline corrosion defects. If the defect depth profile is relatively smooth and does not present multiple major peaks in depth, a corrosion defect can be considered as a regular shape [20]. The shape of the corrosion defect of buried pipelines is simplified as a rectangular volume defects and rounded the corners in this paper, as shown in Figure 1, which is a common used method in literature [13,17,21].

426px
Figure 1. Schematic diagram of corrosion defect pipeline


Numerical analysis of the buried pipeline under the ground loads is conducted by using the FE software ABAQUS6.14. The diameter of the pipeline is 0.66m, and the wall thickness is 8mm. The length of soil along the axial is selected 30 times the pipe diameter, and the height and width are 9 times and 15 times the pipe diameter, respectively, according to the previously published article [1]. Therefore, the whole size of the soil is Failed to parse (MathML with SVG or PNG fallback (recommended for modern browsers and accessibility tools): Invalid response ("Math extension cannot connect to Restbase.") from server "https://test.scipedia.com:8081/localhost/v1/":): {\textstyle 20{\rm m}\times 10{\rm m}\times 6{\rm m}} , and the buried depth is 1m. Considering that the model and boundary conditions have obvious symmetry, a quarter model is used for calculation, in order to improve the calculation efficiency. The FE model of buried corrosion defect pipeline under ground overload is shown in Figure 2. The equivalent pressure is used to describe the ground overload, and the ground overload directly acts on the soil surface above the corrosion defect pipeline, as shown in Figures 2(a) and (c). The pipeline corrosion defect is simplified as a rectangle with rounded corners, and the detailed local shape is shown in Figure 2(d).

The bottom boundary conditions of the model are fixed constraints, and the symmetry constraint is used on the symmetry plane (i.e. the XY plane and the ZY plane). The upper surface of the model is free, and the normal displacement of the outer end faces is restricted to prevent the soil from collapsing. The contact pair algorithm is used to simulate the interface between the outer surface of the pipe and the surrounding soil. And set the friction coefficient as 0.4 [22]. The contact algorithm is widely accepted to simulate the nonlinear behavior of pipe-soil contact, and it can truly simulate the contact force of underground pipeline and soil [2,8].

Test

PERFIL IPE It

calculado

It

Argüelles

[11]

It

Monfort

[12]

It ArcelorMittal

[16]

Iw calculado Iw

Argüelles

[11]

Iw ArcelorMittal

[16]

mm4 x 103 mm4 x 103 mm4 x 103 mm4 x 103 mm6 x 106 mm6 x 106 mm6 x 106
IPE 80 5.59 7.21 7.0 7 119 118 120
IPE 100 8.83 11.4 12.0 12 353 351 350
IPE 120 13.72 17.7 17.4 17 895 890 890
IPE 140 20.35 26.3 24.5 25 1989 1981 1980
IPE 160 28.20 36.4 36.0 36 3976 3959 3960
IPE 180 39.20 50.6 47.9 48 7470 7431 7430
IPE 200 51.65 66.7 69.8 70 13019 12990 13000
IPE 220 70.91 91.5 90.7 91 22774 22670 22700
IPE 240 92.80 120 128.8 129 37624 37390 37400
IPE 270 119.43 154 159.0 159 70871 70580 70600
IPE 300 155.74 201 201.2 201 126379 125900 126000
IPE 330 205.40 265 281.5 282 199841 199100 199000
IPE 360 289.26 373 373.2 373 314510 313600 314000
IPE 400 374.33 483 510.8 511 492215 490000 490000
IPE 450 510.71 659 668.7 669 794312 791000 791000
IPE 500 711.68 918 892.9 893 1254441 1249000 1249000
IPE 550 947.43 1220 1232.0 1230 1893452 1884000 1884000
IPE 600 1329.70 1720 1654.0 1650 2858298 2846000 2846000

Original document

The different versions of the original document can be found in:

http://dx.doi.org/10.1007/978-1-4471-4093-1_13

http://hdl.handle.net/10344/7664

https://ulir.ul.ie/bitstream/10344/7664/1/Gray_2012_Social.pdf

http://shura.shu.ac.uk/6578/1/Ciolfi_23.pdf,https://ulir.ul.ie/handle/10344/7664,https://link.springer.com/chapter/10.1007/978-1-4471-4093-1_13,https://dl.eusset.eu/bitstream/20.500.12015/2757/1/00512.pdf,http://shura.shu.ac.uk/6578,https://rd.springer.com/chapter/10.1007/978-1-4471-4093-1_13,https://academic.microsoft.com/#/detail/1796785663

http://www.springerlink.com/index/pdf/10.1007/978-1-4471-4093-1_13,http://dx.doi.org/10.1007/978-1-4471-4093-1_13

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Document information

Published on 31/12/11
Accepted on 31/12/11
Submitted on 31/12/11

DOI: 10.1007/978-1-4471-4093-1_13_9
Licence: CC BY-NC-SA license

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