Determination of Moisture Condition Values of Bentonite Material Mixed with Salt in Different Water Contents

Abstract

Strength tests available to determine the strength of soils can sometimes be time consuming or
test equipment may not be available. In this case, alternative experiments can be a savior. In terms of the
strength of fillings, there is the MCV test as an alternative to the CBR test. In this study, high plasticity
bentonite material was mixed with different amounts of salt (5, 10, 15, 20, 25 and 30%). To determine the
physical properties, a standard proctor test was performed specifically for each mixture. MCV test was
performed on the mixtures prepared at certain multiples of the optimum water contents obtained from the
Proctor test (0.5, 0.6, 0.7, 0.8, 0.9, 1, 1.1, 1.2, 1.3, 1.4 and 1.5). In this way, the effect of water content
change on MCV was also examined. According to the results obtained, if the water content is more than
20% of the optimum water content, BT20, BT25 and BT30 mixtures do not meet the MCV = 8.5 value
recommended for filling, while BT5, BT10 and BT15 mixtures meet this condition. BT20 mixture give best
performance compared to other mixture when taking into consideration of equation created between water
content and MCV. It was concluded that in mixtures with lower salt content, water content tolerance is
higher than in mixtures with high salt content.