Issue cover

Vol. 6 No. 2 (2026)

View Issue TOC

Structural Assessment of Petroleum Pipeline Crossings Over Flood-Prone Road Corridors in South Sudan

ORIGINAL RESEARCH ARTICLE ORCID 0009-0003-7755-1011
DOI: 10.5281/zenodo.19231169
Published: March 26, 2026

Abstract

: Petroleum pipeline crossings over road corridors represent structurally critical and economically vital infrastructure intersections in South Sudan, a nation where oil revenues constitute more than 90% of government income and where national road networks are subjected to severe seasonal flooding driven by the Sudd wetland hydrological system and intensifying climate variability. This study presents a comprehensive structural assessment framework for both aerial and buried petroleum pipeline crossings over flood-prone road corridors in South Sudan's three principal oil-producing states: Jonglei, Upper Nile, and Unity. Using three-dimensional finite element modelling (FEM) in ABAQUS/Standard, limit state design analysis, scour depth estimation, and field-calibrated hydraulic loading, eight representative crossing sites were evaluated under governing combined load combinations incorporating dead loads, traffic loads, hydrodynamic flood forces, internal operating pressure, and cyclic Vertisol shrink-swell soil loads. Results indicate that unanchored aerial crossings at Jonglei sites experience maximum Von Mises stresses of up to 312 MPa — reaching 87% of the API 5L Grade X52 yield strength — under peak flood and wind loading. Buried crossings are subjected to scour depths of 1.9–2.8 m that exceed minimum burial requirements and generate net uplift forces of up to 4.4 kN/m. A novel composite Pipeline-Road Crossing Vulnerability Index (PRCVI) is proposed, integrating structural, hydraulic, and geotechnical parameters through an Analytical Hierarchy Process (AHP)-weighted formulation. The PRCVI classifies two sites as High Risk and two as Moderate Risk, providing a scalable prioritisation tool for the SSNRA and pipeline operators. Targeted rehabilitation recommendations are

Full Text:

PDF HTML Cover Image PDF

Read the Full Article

The HTML galley is loaded below for inline reading and better discovery.

Open HTML Open PDF

How to Cite

ORIGINAL RESEARCH ARTICLE (2026). Structural Assessment of Petroleum Pipeline Crossings Over Flood-Prone Road Corridors in South Sudan. African Civil Engineering Journal, Vol. 6 No. 2 (2026). https://doi.org/10.5281/zenodo.19231169
EndNote (RIS) BibTeX

Keywords

petroleum pipeline crossingflood-prone roadSouth Sudanfinite element modellingstructural assessmentscour analysisVon Mises stresslimit state design

Research Snapshot

Desktop reading view
Language
EN
Formats
HTML + PDF
Publication Track
Vol. 6 No. 2 (2026)
Current Journal
African Civil Engineering Journal

References

  • World Bank. (2023). South Sudan Economic Update: Oil, Conflict and Development. Washington, DC: World Bank Group. https://doi.org/10.1596/978-1-4648-1985-5
  • Ministry of Roads and Bridges (SSNRA). (2022). National Roads Inventory and Condition Report 2021-2022. Juba: Ministry of Roads and Bridges.
  • Sutcliffe, J. V., & Parks, Y. P. (1999). The Hydrology of the Nile. IAHS Special Publication No. 5. Wallingford: IAHS Press.
  • Tubiana, J., Tanner, R., & Buchanan-Smith, M. (2018). Sudan and South Sudan: Conflict, Livelihoods and Oil Infrastructure. Geneva: Graduate Institute.
  • Rajani, B., & Kleiner, Y. (2001). Comprehensive review of structural deterioration of water mains: Physically based models. Urban Water, 3(3), 151-164. https://doi.org/10.1016/S1462-0758(01)00032-2
  • Lenci, S., & Callegari, G. (2005). Different geometrical formulations of the problem of the elastica with an inflexion point. Continuum Mechanics and Thermodynamics, 17(5), 383-394.
  • Moser, A. P., & Folkman, S. (2008). Buried Pipe Design (3rd ed.). New York: McGraw-Hill.
  • Antaki, G. A. (2003). Piping and Pipeline Engineering: Design, Construction, Maintenance, Integrity, and Repair. New York: Marcel Dekker.
  • American Society of Mechanical Engineers (ASME). (2022). ASME B31.4: Pipeline Transportation Systems for Liquids and Slurries. New York: ASME.
  • American Petroleum Institute (API). (2017). API RP 1102: Steel Pipelines Crossing Railroads and Highways (8th ed.). Washington, DC: API.
  • de Waal, A. (2014). When kleptocracy becomes insolvent: Brute causes of the civil war in South Sudan. African Affairs, 113(452), 347-369. https://doi.org/10.1093/afraf/adu028
  • Nwachukwu, E. C., Atinuke, O. A., & Okonkwo, S. I. (2020). Assessment of road-pipeline crossing failure mechanisms in the Niger Delta, Nigeria. Journal of Pipeline Systems Engineering and Practice, 11(4), 04020033.
  • Ministry of Petroleum and Mining, Republic of South Sudan. (2021). Annual Report on Petroleum Operations 2020. Juba: Government of South Sudan.
  • Sutcliffe, J. V. (2009). The water balance of the Sudd: The seasonally flooded plain of the White Nile. Hydrological Sciences Journal, 39(5), 515-526.
  • Murthy, V. N. S. (2002). Geotechnical Engineering: Principles and Practices of Soil Mechanics and Foundation Engineering. New York: Marcel Dekker.
  • Ethiopian Roads Authority. (2013). Low-Volume Roads Design Manual (Volume 1). Addis Ababa: ERA.
  • Salman, M. A., & Mualla, W. (2008). The utilization of the Nile waters in Sudan. Water International, 33(3), 370-385.
  • Czapiewska, K., Dziewulski, J., & Jurczak, R. (2019). Technical analysis of offshore pipeline on soft seabed. Polish Maritime Research, 26(1), 132-141.
  • American Association of State Highway and Transportation Officials (AASHTO). (2020). AASHTO LRFD Bridge Design Specifications (9th ed.). Washington, DC: AASHTO.
  • Retief, J. V., & Dunaiski, P. E. (2009). Background to SANS 10160: Basis of Structural Design and Actions for Buildings and Industrial Structures. Stellenbosch: SUN Media.
  • Sumer, B. M., & Fredsoe, J. (2002). The Mechanics of Scour in the Marine Environment. Singapore: World Scientific.
  • Melville, B. W., & Coleman, S. E. (2000). Bridge Scour. Highlands Ranch, CO: Water Resources Publications.
  • American Society of Civil Engineers (ASCE). (2022). ASCE 7-22: Minimum Design Loads and Associated Criteria for Buildings and Other Structures. Reston: ASCE.
  • Dassault Systemes. (2022). ABAQUS/Standard User's Manual, Version 2022. Providence, RI: Simulia Corp.
  • American Petroleum Institute (API). (2018). API Specification 5L: Specification for Line Pipe (46th ed.). Washington, DC: API.
  • Watkins, R. K., & Anderson, L. R. (2000). Structural Mechanics of Buried Pipes. Boca Raton: CRC Press.
  • Dey, S. (2014). Fluvial Hydrodynamics: Hydrodynamic and Sediment Transport Phenomena. Berlin: Springer. https://doi.org/10.1007/978-3-642-19062-9
  • Drinnon, R. H., & Spence, M. A. (1994). Pipeline stress analysis at highway crossings. In Proceedings of the International Pipeline Conference, ASME, Calgary. pp. 345-358.
  • Twele, A., Cao, W., Plank, S., & Martinis, S. (2016). Sentinel-1-based flood mapping: A fully automated processing chain. International Journal of Remote Sensing, 37(13), 2990-3004.
  • Federal Highway Administration (FHWA). (2009). Hydraulic Engineering Circular No. 23 (HEC-23): Bridge Scour and Stream Instability Countermeasures (3rd ed.). Washington, DC: FHWA.
  • © 2025 Aduot Madit Anhiem | PARJ Open Access (CC BY-SA 4.0) | ORCID: 0009-0003-7755-1011 | aduot.madit2022@gmail.com