Effect of salinity of water in lime-fly ash treated sand

Abstract

Ensuring sustainable development of coastal areas need improvement of road embankment infrastructure. Being a byproduct of industry, fly ash may be considered as environment friendly and low cost material for this purpose. However, scarcity of fresh water in coastal areas may compel to use saline water. To investigate the effects of sodium chloride content of mixing water on fly ash and lime mixed compacted sand, a series of the unconfined compression tests have been conducted on 50 mm diameter and 100 mm high specimens. Lime content was varied over a range of 1–5% of dry sand weight and fly ash contents were 9, 15 and 30% of dry sand weight. Besides, 0, 4 and 8% of sodium chloride were mixed with tap water, which were used for preparing specimens at 10% moisture content by compaction method. The specimens were cured for 7, 15, 30 and 60 days by spraying method. Experiment results show that, the unconfined compression strength of fly ash and lime mixed compacted sand increases with the increase in sodium chloride content. However, the long term effect of using saline water in fly ash and lime mixed compacted sand should be investigated, which is out of scope of this study.