Experimental Study on the Impact of Type of Sulphate in Lime Stabilised Clays

Authors

Sindhu A R
CUSAT & Assistant Professor, Saintgits College of Engineering, Kottayam, Kerala
Minukrishna P
CUSAT, Kochi–22
B.M. Abraham
AISAT

Synopsis

Marine clays are distinguished by high compressibility and low shear strength. It has been reported that lime stabilisation is very much potent, and can be used as an ideal ground improvement technique in the case of marine clays. Cochin marine clays are sometimes abundant in primary and secondary sources of sulphates of sodium, lithium, potassium and calcium. Different types of sulphates may have different impact on lime stabilised clays. Present study investigates the effect of different types of sulphates in lime treated marine clays. Marine clay samples were collected by auger boring and all the physical properties were determined. Sulphate content in clay was also found. Clay samples were treated with 6% of lime and 4% of sodium sulphate, lithium sulphate and potassium sulphate and were kept for various curing periods of zero days, 1 week, 1 month, 3 months and 6 months. Atterberg limits, free swell index, unconfined compressive strength and pH of all samples were determined. It was found that the plasticity and swelling characteristics of lime treated clay were influenced by the addition of sulphates. It was also found that all the three types of sulphates had detrimental effect on the gain in strength of lime stabilised soil. But the effect varies significantly with the type of sulphate present in the clay. This necessitates the importance of determination of the type sulphate present in the marine clay, before planning the soil stabilisation using lime.

ICCESP 2021
Published
April 11, 2021
Online ISSN
2582-3922