Abstract:
The Raya Kobo town is characterized by kola climate, low rain fall distribution
and the area have high amount of ground water found at average depth of 60
meters and discharge 50 l/sec. average seasonal ground water level fluctuation at
kobo town is 5 to 23 meters.
In the town kobo expansive soil locally called (Walka). This soil damaged many
structures such as building, roads, irrigation canals and other civil engineering
structures built over the soil.
This study is done with the intention of examining the index properties of
expansive soils of kobo, swelling pressure and strength properties based on
secondary data taken from (AWDSW). This secondary data can indicate problem
of soils and provide helpful to estimate of the expected swelling of expansive
soils(walka) of kobo town are generally black in color and have high swelling
potential.
From the secondary data shown free swell and swelling pressure of kobo town
expansive soils indicate that the soil can cause significant damage to light
structures unless proper design and construction measures are taken those
expansive soils have very high shear strength in the dry season and low in the wet
season. Therefore expansive soils of kobo town soil can cause severe damage to
civil engineering structures built in the area; otherwise proper counter measures
are taken.
