Abstract:
Nowadays, the construction of civil engineering structures is increasing from time to time in
Teppi Town as it is a developing town. For this infrastructure, a geotechnical investigation
is mandatory to have a safe structure. Currently, there is no enough detailed geotechnical
investigation that was done for Teppi town. Therefore, this research was aimed to give a
clue on Investigation on some of the engineering properties of soil found in Teppi town. This
study has addressed analyzing the visual identification, index property determination,
compaction characteristics, consolidation, and shear strength analysis by taking the
disturbed and undisturbed samples from ten test pits. The sampling procedure and tests were
based on American society for testing material (ASTM) manual standards. A selected test
pit was dug out with hand tools of a disturbed and undisturbed soil sample then taken to the
laboratory to test the index and engineering properties of the study area, the laboratory test
types, which was conducted at the average depth of 1.5m and 3.0m were moisture content,
Atterberg limit, sieve analysis, standard compaction, etc. The result of the study shows that
the natural moisture content varies from 32.18% to 59.45%. The specific gravity varies from
2.53 to 2.78. The majority of soils were categorized as fine-grained soils from which more
than 50% of the particle sizes are smaller than 0.075 mm except from two test pits in which
they are coarse-grained soil. The liquid limits range from 55% to 104% and plastic limits
vary from 25% to 57%. The free swell ranges from 40% to 100%. Based on the free swell
index result most of the study area soil was experiences a very high degree of expansiveness,
and two tests pit degree of expansiveness belong high. The investigated sample has an
undrained shear strength value ranging from 72.11 kPa-131 kPa as shown by the unconfined
compression strength test. The compression index value ranges from 0.28 to 0.40. Within
the depth of the exploration, the compaction test shows that the maximum dry density of the
teppi soil is between 12.96 KN/m3
to 15.45 KN/m3
and the optimum moisture content ranges
from 19.5% to 35.80%. A comparison was made in is this study with previously done
research in other parts of Ethiopia. The comparison indicates that the engineering
properties of these soils of the study area soil lies within the range of different researchers
in the other part of the country
