Vol. 4 No. 3 (2026)
Comparative Performance of Asphalt Pavement on East African Community Highway Corridors
Abstract
Asphalt pavement performance across the East African Community (EAC) highway network is critically compromised by a combination of high ambient temperatures, axle overloading, seasonally high rainfall, and maintenance underfunding. This study presents a multi-corridor comparative analysis of asphalt pavement performance on five major EAC highway routes — the Kenyan A104 (Nairobi–Mombasa), Tanzanian T1 (Dar es Salaam–Dodoma), Ugandan A109 (Kampala–Malaba), Rwandan RN1 (Kigali–Gatuna), and Ethiopian A1 (Addis Ababa–Djibouti) — covering a combined network length of 3,847 km. Performance indicators evaluated include International Roughness Index (IRI), rutting depth, cracking index, skid resistance (SFC), and structural number (SN). Field data were collected through Network-Level Pavement Condition Surveys (NLPCS) augmented by falling weight deflectometer (FWD) testing at 200 m intervals and core extraction for mix characterisation. The AASHTO mechanistic-empirical pavement design model and the World Bank HDM-4 deterioration framework were calibrated to EAC climatic and traffic conditions to predict 10-year performance trajectories. Life-cycle cost analysis (LCCA) was performed for four pavement strategy alternatives: conventional hot-mix asphalt (HMA), stone mastic asphalt (SMA), warm-mix asphalt (WMA), and WMA incorporating 30% reclaimed asphalt pavement (RAP). Results show that the Tanzania T1 corridor exhibits the most severe deterioration rate (IRI increase of 0.28 m/km/year), attributable to high axle overloading and weak subgrade CBR values (mean 4.8%). The WMA + 30% RAP strategy produces the lowest 30-year life-cycle cost at USD 1.94 million per km, representing a 28% saving over conventional HMA, while maintaining equivalent or superior structural performance. Reco
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- AASHTO (1993). AASHTO Guide for Design of Pavement Structures. American Association of State Highway and Transportation Officials, Washington, DC.
- Brown, E. R. and Brunton, J. M. (2017). Rutting of asphalt pavements: causes, measurement and remediation. Transport Research Laboratory Report TRL484, Crowthorne.
- EAC Secretariat (2022). East African Community Infrastructure Master Plan 2023–2040: Roads and Bridges Sector Assessment. EAC Secretariat, Arusha.
- EAC (2023). East African Community Infrastructure Master Plan 2023–2040 — Final Report. EAC Secretariat, Arusha, Tanzania.
- FHWA (2014). Life-Cycle Cost Analysis in Pavement Design: Interim Technical Bulletin. Publication No. FHWA-SA-98-079, Federal Highway Administration, Washington, DC.
- Gitau, A. N., Odoki, J. B. and Kerali, H. R. (2020). Pavement performance modelling on the Tanzanian highway network using HDM-4. International Journal of Pavement Engineering, 21(3), 312–325.
- ISO 13473-1 (2019). Characterization of Pavement Texture by Use of Surface Profiles. International Organization for Standardization, Geneva.
- Kenya Roads Board (2009). Design Manual for Roads and Bridges. Roads Design Manual Part III: Pavement Design. Ministry of Roads, Nairobi.
- Muraya, P. M. (2016). Permanent deformation of asphalt mixes on Kenyan highway network. Construction and Building Materials, 102, 622–631.
- Nunn, M. (2017). An Investigation into the Performance of Stone Mastic Asphalt. Transport Research Laboratory Report TRL 345, Crowthorne.
- Odoki, J. B. and Kerali, H. R. (2010). Analytical Framework and Model Descriptions — HDM-4 Volume Four. World Road Association PIARC, Paris.
- Paterson, W. D. O. (2018). Road Deterioration and Maintenance Effects: Models for Planning and Management. World Bank Transport Research Paper, Washington, DC.
- Rowe, G. M. (2019). Performance of Stone Mastic Asphalt in High-Temperature Environments. NCAT Report 19-04, Auburn University.
- RTDA (2022). Rwanda National Road Network Performance Report 2021–2022. Rwanda Transport Development Agency, Kigali.
- SSATP (2019). Africa Transport Policy Program: Overloading in Sub-Saharan Africa — Trends and Policy Responses. SSATP Working Paper No. 109, World Bank, Washington, DC.
- TANROADS (2015). Tanzania Pavement and Materials Design Manual. Tanzania National Roads Agency, Dar es Salaam.
- Uganda MoWT (2018). Draft Roads Design Manual: Pavement and Materials Design. Ministry of Works and Transport, Kampala.
- Uzan, J., Witczak, M. W. and Scullion, T. (2012). Development and Validation of Realistic Pavement Response Models. Proceedings of the 8th International Conference on Asphalt Pavements, ISAP, Seattle.
- Witczak, M. W. and Fonseca, O. A. (2015). Revised Predictive Model for Dynamic (Complex) Modulus of Asphalt Mixtures. Transportation Research Record 1540, TRB, Washington, DC.
- World Bank (2021). East Africa Regional Integration: Road Corridor Performance Review 2020–2021. World Bank Group, Washington, DC.
- World Road Association PIARC (2020). Pavement Maintenance Performance Indicators: Guidelines for Network-Level Assessment. PIARC Technical Report 2020R03, Paris.
- Yang, Q. and Lundberg, A. (2018). Effect of temperature on dynamic modulus and rutting resistance of asphalt mixes in tropical climates. Road Materials and Pavement Design, 19(5), 1102–1120.
- Zaabar, I. and Chatti, K. (2010). Calibration of HDM-4 models for estimating the effect of pavement roughness on fuel consumption for U.S. conditions. Transportation Research Record 2155, 105–116.