Abstract:
A solution available to engineers for facing the problem of unsuitable soils for road subgrade
is the stabilization processes. Among then the use of chemical additives has gained popularity,
particularly the last decade. The poor engineering characteristics of soils could be enhanced
under the action of various agents and controlling factors, like the pozzolanic activity, the
cation exchange and other already recognized reactions taking place in the soil additive
complex.
This paper investigates the improvements in the properties of expansive soils, as road
subgrade stabilized with lime in varying percentages. Laboratory tests were undertaken to
study the swelling and strength characteristics of expansive soils stabilized with lime. Limes
were added separately to expansive soil start from 5% to at ranges of 2.5% increment .Index
property, compaction, California Bearing Ratio (CBR), Unconfined Compression Strength
(UCS), free swell and swelling pressure tests were performed on natural and treated soil
samples. For the investigated admixture lime; the amount of lime added 5% 7.5%, and 10%
.Comparing the results obtained of the natural and treated samples, the CBR and UCS of lime
treated samples increased significantly, coupled with the swelling reduction, depending on
additive content. It could be concluded that stabilization of expansive subgrade soils by lime
admixture is successful and more economical.
