Roads are essential to the development of a nation, as they facilitate transportation and economic growth. Pavements, which provide a durable surface for vehicle traffic, depend on a variety of factors, including the quality of Unbound Granular Material (UGM) used in their base layers. The main objective of this review article was to review recent studies on the characterization of UGM in pavements. To do this, a bibliometrics study was carried out to confirm the scientific interest of the subject by revealing a large number of publications on pavements and gravels not treated on the subject since 2000. It appears that various empirical and theoretical approaches are used in pavement design and that UGM properties play a crucial role in the structural integrity of pavements. Indeed, the study showed that UGM cleanliness is crucial to avoid contaminants that can affect the quality and performance of building materials. Various methods, including digital image analysis, have been used to quantify the characteristic shape of UGM. Additionally, UGM resistance is achieved using tests such as the Los Angeles abrasion test, which measures impact resistance. The researchers also underline the importance of taking into account cyclic stresses and permanent deformations in the design of the pavement to improve its longevity. In conclusion, the article highlights the growing scientific interest in pavements with UG base layers and discusses various methods for characterizing UGM properties, which are essential for the design of durable and resilient road pavements.

This study is part of general problem of developing innovative buiding materials with low environmental impact. For this purpose, tests were carried out for the formulation of cementitious composites based on rhun fibers (borassus aethiopum mart.) and rice huks. The results allowed to obtain the optimal proportion in biomass particles and water content which lead to the best physical and mechanical properties of the composites. Thus, in the case of cement and rice husks mixtures, mechanical strengths decrease with an increase of particle size. On the other hand, in the case of rhun fibers composite, mechanical resistance increase with fibers size. The results also show that physical and mechanical properties of rhunr fibers composites are better than those based on rice husks.