TITLE:
Effects of Soil-Cement Stabilization on the Index Properties of Subgrades of Three Selected Roads in the Niger Delta Region of Nigeria
AUTHORS:
Jonathan O. Irokwe, Ify L. Nwaogazie, Samuel Sule
KEYWORDS:
Soil-Cement Stabilization, Expansive Soils, Maximum Dry Density, Disturbed Soil Samples, Index Properties, Optimum Moisture Content
JOURNAL NAME:
Open Journal of Civil Engineering,
Vol.12 No.4,
December
30,
2022
ABSTRACT: In this study, the impact of soil-cement stabilization on the index
properties of the subgrade of roads was investigated. Efforts were on the means
of improving the bearing capacity of the subgrade of a flexible pavement
structure. Three selected roads (Ogbia-Nembe, section of the East-West Road and
section of Port Harcourt-Aba Road) in the Niger Delta Region of Nigeria were
examined to determine the effect of sand-cement stabilization on the compaction
index property of their undisturbed subgrade and the optimal ratio of soil-cement
on the expansive soils at which the California Bearing Ratio (CBR) is
optimized. Disturbed soil samples were collected from twenty trial pits on each
of the three study roads using a hand
ulger and tested for their respective compaction index properties. It was discovered
that their California Bearing Ratio (CBR) was very
low. Some of the collected specimen materials were stabilized with varying
percentages of soil-cement contents ranging from 6% - 14% in
order to ascertain its effects on the compaction index properties of the sample
soils. Results of the various stabilization test procedures show that:
Stabilization of the soil using Soil-Cement Stabilization affected the
Compaction Index properties of the soil and further improved the California
Bearing Ratio (CBR). On the Ogbia-Nembe Road;
Soil-Cement stabilization improved the CBR and is optimized at a 10% sand-cement
ratio with optimum moisture content ranging from 6.2% - 14%, maximum dry density ranges from 1700 - 1780 kg/m3, yielding an average CBR of 42.7% for soaked
samples. On the section of East-West Road from Eleme Junction to Etteh
Junction; Soil-Cement stabilization improved the CBR and is optimized at a 14% sand-cement ratio with optimum moisture content
ranging from 6.2% - 14.2%, maximum dry density ranges from 1660 - 1800 kg/m3, yielding an average CBR of 43.9% for soaked
samples. On the section of Port Harcourt-Aba Express Road from Eleme Junction
to Osisioma Junction; Soil-Cement stabilization improved the CBR and is
optimized at a 12% sand-cement ratio having an optimum moisture content ranging
from 5.4% - 17.3%, maximum dry density ranges from 1610 - 1740 kg/m3, and an average California Bearing Ratio for soaked
samples at 40%.