Methods
Determination of the chemical composition of the rice husk ash and soil
sample were determined by means of gravimetric method.
The soil sample was subjected to preliminary tests, such as the particle
size distribution, specific gravity and Atterberg limits. The natural
soil samples were also subjected to compaction tests and the California
bearing ratio (CBR).
The soil samples were later treated with cement at values of 0, 2, 4, 6,
8, 10 and 12% which were separately mixed with rice husk ash (RHA) at
varying proportions of 2, 4, 6, 8, 10, 12, 14 and 16%. These samples
were each subjected to Atterberg limits, compaction and California
bearing ratio. The entire tests were carried out according to BS 1377[12] for natural soil samples and British Standard
1924 [24] for stabilized samples.
Results from the laboratory tests especially that of the liquid limit,
plasticity index, maximum dry density, optimum moisture content, the
percentages of cement and rice husk ash served as inputs which were
employed in developing the Artificial neural network (ANN) model for
predicting soaked and unsoaked CBR values of the stabilized soils.