INVESTIGATING CAUSES OF FLEXIBLE PAVEMENT FAILURE: A CASE STUDY OF THE BAKO TO NEKEMTE ROAD, OROMIA, ETHIOPIA
Abstract
Most of the roads constructed in Ethiopia fail prematurely before serving the design life due to various causes arising from many factors. One of the roads that failed before reaching its design lifetime is the Bako to Nekemte Trunk Road. This road was constructed and opened to traffic in 2013. The design pavement life was estimated at 20 years. However; pavement failures have manifested since 2014 after it was opened for traffic. The main objective of this research was to investigate the cause for the failure of flexible pavement on the Bako to Nekemte road segment. To achieve this objective, the study was followed by the experimental research type and purposive sampling method. Also, field observation and pavement condition survey methods for data collection were used. The asphalt, base course, subgrade, and sub-base layer material sampled from the road segment are the material used for this study. Different pavement failures such as rutting, pothole, alligator cracking, raveling, edge cracking, depression, and corrugation were observed along the road section. For estimations of pavement condition index, the road was divided into five different sections based on distress densities, which were measured during the pavement condition survey. From those five sections, four sections were selected for the determination of the Pavement Condition Index (PCI). Using systematic random sampling 159 sample units were evaluated for Pavement Condition Rating (PCR) and the result shows 1.89% excellent, 8.18% very good, 20.13% good, 31.45% fair, 18.87 % poor, 18.24% very poor, and 1.26% failed. Based on PCI value, samples of pavement layer were taken from failed surface condition (1), poor surface condition (2), and none distressed area (1) for comparison purposes. Different quality tests like Atterberg limit, wash gradation, soil classification, compaction test, California Bearing Ratio (CBR), Los Angeles Abrasion (LAA), Flakiness Index ( FI), Aggregate Crushing Value (ACV), Ten percent fines value (TFV), bitumen content, and gradation of asphalt were carried out. The results of these tests were compared with ERA specifications to identify the probable cause of pavement failure. The study found that the cause for failure of flexible pavement in the case of Bako to Nekemte was: insufficient and absence of side drainage structure, traffic loading, poor gradation of base course and sub-base material, and poor quality of subgrade soil. The study also recommended that the road urgently needed routine maintenance as a treatment option to reduce further deterioration and extend its service time.
References
Zumrawi, M. M. E. (2016). Investigating causes of pavement deterioration in Khartoum State. Int J Civ Eng Technol, 7(2), 203–214. https://doi.org/10.5281/zenodo.1110059
Geremew, A., Quezon, E. T., & Kebede, G. (2016). Influence Of Subsurface Courses Materials On Pavement Performance: A Case Study in Yebu-Agaro Road. International Journal of Scientific & Engineering Research, 7(10), 1252–1260.
Jemal, A., Agon, E. C., & Geremew, A. (2019). Utilization of crushed stone dust as A stabilizer for sub grade soil: A case study in Jimma town. Annals of the Faculty of Engineering Hunedoara, 17(4), 55–64.
Geremew, A. (2018). Experimental Performance Studies on the Improved Expansive Subgrade Soil Formation by Using Mechanical Stabilization with Natural Gravel Around Jimma Quarry Sites. American Journal of Civil Engineering, 6(5), 154. https://doi.org/10.11648/j.ajce.20180605.13
Kõrbe Kaare, K., Kuhi, K., & Koppel, O. (2012). Tire and pavement wear interaction monitoring for road performance indicators. Estonian Journal of Engineering, 18(4), 324. https://doi.org/10.3176/eng.2012.4.04
Fentaw, M., Alemayehu, E., & Geremew, A. (2021). Experimental Study of Stabilization of Expansive Soil Using the Mixture of Marble Dust, Rice Husk Ash And Cement for Sub-Grade Road Construction: A Case Study of Woldia Town. Journal of Civil Engineering, Science and Technology, 12(2), 141–159. https://doi.org/10.33736/jcest.3977.2021
N C, O. (2020). Causes of Failure of Flexible Pavement (a Case Study of Awka-Ugwuoba Section of the Old Enugu-Onitsha Expressway).
Emmanuel, U. O., Ogbonnaya, I., & Uche, U. B. (2021). An investigation into the cause of road failure along Sagamu-Papalanto highway southwestern Nigeria. Geoenvironmental Disasters, 8(1), 3. https://doi.org/10.1186/s40677-020-00174-8
Ekwulo, E. O., & Eme, D. B. (2009). Fatigue and rutting strain analysis of flexible pavements designed using CBR methods. African Journal of Environmental Science and Technology, 3(12). https://doi.org/10.5897/AJEST09.018
Ragnoli, A., De Blasiis, M., & Di Benedetto, A. (2018). Pavement Distress Detection Methods: A Review. Infrastructures, 3(4), 58. https://doi.org/10.3390/infrastructures3040058
Adeke, P. T., Atoo, A. A., & Orga, S. G. (2019). Assessment of pavement condition index: a case of flexible road pavements on the university of agriculture Makurdi Campus. Nigerian Journal of Technology, 38(1), 15. https://doi.org/10.4314/njt.v38i1.3
Qiao, Y., Dawson, A. R., Parry, T., Flintsch, G., & Wang, W. (2020). Flexible Pavements and Climate Change: A Comprehensive Review and Implications. Sustainability, 12(3), 1057. https://doi.org/10.3390/su12031057
Llopis-Castelló, D., García-Segura, T., Montalbán-Domingo, L., Sanz-Benlloch, A., & Pellicer, E. (2020). Influence of Pavement Structure, Traffic, and Weather on Urban Flexible Pavement Deterioration. Sustainability, 12(22), 9717. https://doi.org/10.3390/su12229717
Abubakar, M., Belel, Z., & Abba, H. (2012). Road Pavement Failure Induced by Poor Soil Properties Along Gombi-Biu Highway, Nigeria. Journal of Engineering and Applied Science.
PLC, S. E. (2006). Review of Feasibility Study, Review of EIA, Preparation of Resettlement Action Plan & Review of Detailed Engineering Design and Tender Documents, Gedo-Nekemte Road Upgrading Project Review of Environmental Impact Assessment Report.
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