David Bilembi¹, Hilaire Elenga², Timothée Nsongo^3,, Bernard Mabiala⁴, Adolphe Kimpena⁵, Balla Diop Ngom^6,, Aboubaker Chedikh Beye⁶

The survey of the road construction materials within the Brazzaville Area in the Congo was conducted on the geotechnical data of materials collected from different sites in order to establish a correlation with the norms of their use in Civil Engineering fields. These data include grading curves, consistency limits for the fine fraction, modified Proctor test results and CBR tests. Those data were subjected to classical statistic processing (characterization of every geotechnical parameter variability, study of correlations between parameters). The survey concludes that the material samples analyzed present so close physical properties that they cannot be clearly distinguished through statistical analysis. The overall analysis of the CBR index values varies depending on the materials used. As a consequence these variations cause the deterioration of the pavement structure. The constituents that comply with the above-defined physical properties can be used as materials of a pavement structural layer. The deterioration effects and the granular fragmentation from the Inkisi formations help appreciate the Micro-Deval coefficient and the Los Angeles coefficient, for the figures of both coefficients and result in high figures which means better basic mechanical properties of the foundation and structural layers.

materials, physical properties, mechanical properties, proctor tests, CBR tests