The CBR index is a fundamental parameter used in the construction of the earth works or the bearing layers of roadways. The measurements carried out on the swelling clayey soils show that it is still very weak. CBR measurement tests carried out on the swelling clays and sand compounds in the Far North region of Cameroon indicate that with a 40% sand content and a compactive effort of 25 strokes, the CBR of the swelling clay of Maroua moves from 1.27 to 5.58 and that of Fotokol from 2.18 to 5.26. For a sand content of 30% (resp. 40%) and a compactive effort of 55 strokes, the swelling clay from Maroua moves from 4.3 to 5.31 (resp. 4.3 to 7.9) and that of Fotokol from 3.54 to 5.69 (resp. 3.4 to 7.59) for water content values ranging between 12.11% and 19.79%.
