DISTRIBUTION OF ENGINEERING PROPERTIES OF SOILS USED IN HIGHWAY CONSTRUCTION IN NIGERIA

📄 Project Abstract

Areas with alluvium (Qa) soil from the Quartenary Era, have A-2-4, A-2-6, and A- 2-7 classifications according to the AASHTO Soil Classifications, while areas with sands and clays (Qp) from coastal plain sands are mainly classified as A-7-5, and A-7-6 with few locations having A-2-4, A-2-6, and A-2-7 classifications. Also, sands and clays (Qc) from Chad formation of Quaternary Era have A-2-4, A-4 and A-6 classifications. Sands, clays, and shales (Ti) of Illaro formation from the Tertiary era are of A-7-5 classification. Shales and roundstone (Kro) of Nkporo shale group formed from cretaceous era have A-7-5, A-2- 7 and A-6 classification; Shales, and limestone (Kwn) of Agwu-Ndeaboh shale group formed from cretaceous era are classified as A-6, A-2-7, and A-7-5; while black shale and siltstone (Kea) of Eze Aku shale group formed from cretaceous era have A-2-6, and A-7-6 classifications. Granitoids (Pcg) of older granites series in basement complex formed from Pan Africa era are mainly A-7...