Abstract:
Modification of soils at a construction site to improve engineering properties is essential
in many applications (e.g. highways, subgrades, earth dams, building foundations and
earth-retaining structures) to improve their engineering properties. Mechanical
compaction is used as a practical means of achieving the desired strength,
compressibility and hydraulic conductivity characteristics of soils. The compaction curve
and associated characteristics namely maximum dry unit weight and optimum moisture
content are determined in the laboratory using compaction test procedures. The test not
only requires significant time and effort to carry out, but also require relatively large
quantity of soil. Hence, there is a necessity to predict compaction characteristics of soils
with the help of correlation analysis with the index properties of soils, which can be
determined easily. The study focused on the development of the statistical model between
moisture density relation and index properties of lateritic soil specifically located in
Durame town. For this purpose, 30 samples collected, and a series of laboratory tests
conducted. The parameters considered for this study are Atterberg's limits, Grain size,
Specific gravity, and Compaction tests. The test procedures based on American Society of
Testing and Materials laboratory test standards. Results indicated, the soil type found in
Durame town composed of inorganic highly plastic latritic red clay soil, and inorganic
silts of high plasticity. In the analysis part, both the MS excel spreadsheet and the SPSS
software had used for the scatter plot, correlation, and regression analysis. Based on
both single and multiple linear regression analysis, relatively good correlation was
obtained by combining plastic limit and liquid limit with maximum dry density and
optimum moisture content of lateritic soil. From the correlation analysis, the equations
developed are MDD = 1.765 - 0.004LL with coefficient of determinant of 0.831, and
OMC = 13.798 + 0.278LL with coefficient of determinant 0.884 for single linear
regression, and MDD = 1.758 - 0.002LL - 0.005PL with coefficient of determinant
0.887, OMC = 13.924 + 0.225LL + 0.1PL with coefficient of determinant of 0.908 for
multiple linear regression, respectively.
It has been shown that these models will be useful for a preliminary design of earthwork
projects which involve lateritic soils in Durame town.
