Application of Slag Compound as a Curing Agent for Dealing With Salt Expansion in Coastal Saline Soil

Abstract

Because of high concentration of soluble salt in coastal saline soil, it might cause salt expansion to some extent. In this paper, the application of slag compound as a curing agent (referred to as SM) for dealing with salt expansion in saline soil is investigated. This has done through studying the coefficient of salt expansion characteristics of the soil stabilized by slag compound. The test results approve that the SM improves saline soil’s salt expansion and can make a soil characterized as expansible to the one with no salt expansion. Furthermore, SM decreases the coefficient of salt expansion after hydration by turning into crystal and gel formation, which improves the strength of soil samples and reduces the expansion of crystalline salts. On the other hand, SM reacts with the soluble salt in saline soil, which reduces the content of soluble salt and reduces the precipitation of crystalline salt and therefore lowers the coefficient of salt expansion. The study also compared the curing applications of SM, cement and quick lime. SM and cement have been found to have similar impacts on saline soil’s salt expansion, whilst SM has been identified as a more economically viable option. Quick lime, however, is shown to have less curing application compared with both SM and cement. Thus, utilizing SM for improving saline soil’s salt expansion has been proved to not only be technically feasible, but also economically viable.