Abstract:
Characterizing field material properties by using laboratory tests is an ongoing problem
in the discipline of geotechnical investigations. It is difficult to collect and test
representative samples, and because of this, there is a discrepancy between laboratory
test results and in situ soil conditions of environment. This usually leads us to use of
unreliable designing methods. To avoid such problems Correlations Dynamic Cone
Penetration Index (DCPI) with Unconfined Compressive Strength (UCS) and index
properties that make it interesting alternative, due to operating quickly, very light,
versatile and user-friendly property of DCP . The dynamic cone penetrometer (DCP)
which is a simple test device that is inexpensive, portable, and easy to operate and
understand. Unconfined Compressive Strength (UCS) is one of the type of laboratory
testing. This laboratory testing is conducted by undisturbed samples. It is difficult to
obtain accurate undisturbed samples. Even some designers or companies do not conduct
soil investigation for building. Some of these predictions may leads to unexpected failures
of structure or uneconomical design. So, prediction of Unconfined Compressive Strength
for cohesive soil with the help of Dynamic Cone Penetration Index (DCPI) and index
properties of soil provides a good alternative to minimize this problem. To this end, the
present research aimed to develop single and multiple correlations of UCS, DCP and
index properties of soil and also compare, validate and evaluate the developed model
using the controlled test and with related existing model. This research consists of field
testing, laboratory testing, and analysis of the results for 30 samples from 15 test pit
collected from different location of town. By using the test result regression based
statistical analysis was carried out to develop the intended correlation. The parameters
considered for this study are Natural moisture contents, Atterberg limits, dry unit weight
and specific gravities. The test procedures were based on ASTM laboratory test
standards. Regression models were develop using SPSS software and Microsoft Excel for
this study to enable the prediction of UCS values. From the study predicting Unconfined
compressive strength (UCS) is obtained from multiple linear regression analysis and
given by UCS = 202.211-0.673 DCPI +6.03ɣdry -0.406LL -1.511NMC, coefficient of
determination (R²) = 0.918 .The results are expected to have wide application in the
construction sector
