Geotechnical Behavior of Soil–Fly Ash–Cement Mix as Liner Material in Irrigation Canal

The increasing demand in electricity triggers the generation of huge quantity of fly ash, a waste material. On the other hand, the irrigation canal used in the agricultural land often encounters with the problem of water seepage. This research investigates the feasibility of using a combination of fly ash and soil as a lining material for irrigation canals. Laboratory tests were conducted to study the geotechnical properties of the lining material consisting of soil, fly ash and cement. Compacted samples were underwent unconfined compression tests, permeability tests and direct shear tests. The soil is mixed with 20, 30, 40, 50, 60, 70 and 80% of fly ash. Results indicate that adding fly ash enhances the unconfined compressive strength but initially reduces permeability. Generally, reduction in shear strength of soil has been observed with increasing fly ash content. Introducing cement to the soil–fly ash blends further improves the unconfined compressive strength and influences permeability. At 4% cement content, the cemented soil–fly ash mix also shows improvement in shear strength and permeability as compared to other types of soil mixes. Based on the laboratory test results, an optimum mix of soil–fly ash–cement has been selected for the construction of a model of irrigation canal used in the locality. Considering the satisfactory performance of the mix prepared, it can be concluded that there is a potential of using soil–fly ash mix with cement as a lining material in irrigation canal.