Akademik Veri Yönetim Sistemi
V. International Turkic World Congress on Science and Engineering, Bishkek, Kırgızistan, 15 - 17 Eylül 2023, ss.1-12
Expansive clays are a worldwide problem that poses several
challenges for civil engineers. Such clayss swell when given an access to water
and shrink when they dry out. Expansive clays can be stabilized by using
admixtures. In this study the effect of using zeolite and lime in reducing the
swelling potential of an expansive clay is
examined. According to the ASTM C-618 standard zeolite is considered as a pozzolanic
material. Grain size distribution, Atterberg limits and swell percent of the
zeolite-lime- expansive clay mixtures are determined. Specimens are cured for 7
and 28 days. As a result of the experimental study, it was seen that addition
of zeolite and lime mixture decreased swelling potential of the artificially
prepared expansive clay specimen. The swell percentage of the stabilized
specimens are affected positively by curing. The
decrease in swell potential is due to zeolite - lime - expansive clay
reactions, In the first phase, Ca2+ cations of the lime replace the
sodium (Na+) ions of expansive clay, this reaction reduces the
thickness of the diffuse double layer which will cause flocculation and
reduction in the plasticity of the soil. Hydration of lime with water liberates
(OH)- ions which will cause increment in the pH of the soil
solution, this will lead to increment in the solubility potential of silica and
alumina and leads to a pozzolanic reaction and in the second phase, the
cementing compound (CSH and CAH) gradually bonds the clay particles together. Curing
positively affects the pozzolanic reactions.