TEXTURE AND CEMENT STABILIZATION OF DREDGED SAND USED FOR OGBIA – NEMBE ROAD, BAYELSA STATE, NIGERIA

Abstract

This paper is aimed at determining the texture, compaction, and cement stabilization properties of the dredged sand used in the Ogbia-Nembe road construction in Bayelsa State, Nigeria. Both field and laboratory studies were undertaken. Results from the laboratory tests revealed the various properties as follows: moisture content (41.3 – 58.2%), Liquid limit (45.5 – 50.5%), Plastic limit (26.2 – 33.7%), Plasticity Index (16.8 – 20.6%), Cu (2,15 – 3.16), Optimum moisture content (OMC) and Maximum dry densities (MDD) for the dredged sands are (9.2 – 9.4) and (1600 – 1620kN/m3 respectively. The OMC, MDD and California bearing ratio (CBR) of the sand-cement mixture are 10.2 – 12.6%, 1830 – 1880kN/m3, 177 -313% and 1140 -2905kN/m2 respectively. The dredged sands are classified as A-3 according to the AASHO classification system. However, the average MDD of the dredged sand is 1620kN/m3 which is below the Federal Ministry of Works (FMW) specification for pavement construction, therefore the need for stabilization. Stabilization of the sand with 6% – 10% cement increased the MDD, CBR, UCS to 1880kN/m3, 313% and 2905kN/m2, respectively. The results of this study revealed that the minimum percentage of cement required to stabilize the dredged sand used for the construction of the road is 6%. Also, particle size of cohesionless soil affects the density and sand-cement stabilization is more economical than paying for additional maintenance cost if the pavement fails. This study also revealed that increasing the percentage of cement of a sample does make the soil brittle as well as increases the strength of the material/soil.