1Laboratory of Energy and Applied Mechanics (LEMA), Polytechnic School of Abomey-Calavi (EPAC), University of Abomey-Calavi (UAC), Republic of Benin.
2Laboratory of Engineering Sciences and Applied Mathematics (LSIMA) of the National University of Sciences, Technologies, Engineering and Mathematics of Abomey (UNSTIM), Abomey, Benin
American Journal of Civil Engineering and Architecture.
2026,
Vol. 14 No. 4, 146-154
DOI: 10.12691/ajcea-14-4-2
Copyright © 2026 Science and Education PublishingCite this paper: Kocouvi Agapi HOUANOU, Constant Euloge ADJAGBONI, Jean-Louis Comlan FANNOU, Kpomagbé Serge DOSSOU, Antoine VIANOU. Study of the Effect of Compaction Rate on the Thermal Diffusivity of an Unbound Granular Road Material: The Case of Lateritic Gravel.
American Journal of Civil Engineering and Architecture. 2026; 14(4):146-154. doi: 10.12691/ajcea-14-4-2.
Correspondence to: Kocouvi Agapi HOUANOU, Laboratory of Energy and Applied Mechanics (LEMA), Polytechnic School of Abomey-Calavi (EPAC), University of Abomey-Calavi (UAC), Republic of Benin.. Email:
agapi.houanou@uac.bjAbstract
In the context of road construction in the intertropical zone, lateritic gravel is a predominant material due to its availability and geotechnical characteristics. This article examines the influence of compaction rate on the thermal diffusivity of lateritic gravel. For this study, samples of lateritic gravel from Cana Atchia, Zogbodomey commune, Zou department in Benin, were compacted to rates of 90%, 95%, 97%, and 100% in PVC cylinders. For each of these specimens, thermal diffusivity was determined using a numerical method that solves the heat equation in quasi-steady state based on data collected via an experimental setup comprising a heating lamp as the heat source and a data acquisition system with Type K thermocouples to monitor temperature changes within the material. At the same time, the CBR was measured at the various targeted compaction rates, both on unheated specimens and on those used to measure thermal diffusivity. The results obtained demonstrate a direct correlation between an increase in the compaction rate and an improvement in the material’s thermal properties. The average thermal diffusivity increased from 4.834×10−7m²/s at 90% compaction to 5.774×10−7m²/s at 100%. This increase is explained by the reduction in the material’s porosity, which facilitates better heat propagation through the densified particles. Additionally, it was noted that heating caused the CBR values to drop. However, the CBR increases with the compaction rate regardless of the type of specimen. This study confirms that optimizing the compaction of lateritic gravel is an effective means of improving its thermal performance, which reduces its strength performance. Better control of heat diffusion is essential for designing more stable and durable road infrastructure in tropical climates, thereby helping to reduce damage and long-term maintenance costs.
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