Akademik Veri Yönetim Sistemi
International Advanced Researches and Engineering Journal, cilt.4, sa.3, ss.1-12, 2020 (TRDizin)
Consistency limits are essential and
simple design parameters that are utilized as standard entries of all kinds of
soil investigation programs conducted for geotechnical projects which are
constructed in/on fine grained soils. These limits also represent mineralogical
and physical properties of clayey soils directly and used to estimate their
strength and rigidity properties indirectly. However, the consistency tests are
assumed as the simple and basic tests of geotechnical engineering
investigations, but the effects of operator, calibration of the device and
environmental aspects at the tests endamage the reliability and correctness of
results. In this paper, it is aimed to overcome these challenges by evaluating
the consistency characteristics of clayey soils considering only the values of
liquid limit of specific clays with the use of simple regression analysis. A database
is prepared by using 500 soil investigation reports that are involving the site
characterization information, laboratory and field tests of Istanbul Province
European side clayey soils, including Avcılar, Esenyurt, Küçükçekmece,
Büyükçekmece, Çatalca, Zeytinburnu, Bahçelievler, Bakırköy districts. 1523
liquid limit tests are obtained from the mentioned database for high and very
high plastic clays. The regression analyses have been applied to query the
parameter effect ratio on the consistent characteristics and relationships have
been tried to be developed to evaluate the values of plastic limit and
plasticity index directly from only liquid limit test applications. The effects
of fine material content, depth and natural water content is also investigated.
Verifications of the suggested equations have been done for different cases and
comparisons are made with the well-known sources of literature. Consequently,
strong equations are acquired to determine the plasticity index value in terms
of liquid limit, liquid limit-depth, liquid limit-fine content, natural water
content-fine content respectively based on the actual experimental tests
conducted in Istanbul.