A study of the performance of lignosulfonate-treated high plastic clay under static and cyclic loading

Traditional stabilizers such as cement and gypsum have been reported to increase the strength; however, make the soil excessively brittle which is undesirable in case of structures subjected to cyclic loading. Therefore, an alternative material that can improve the strength and durability without altering the ductility of soil specimens is required. In the present study, a lignin-based chemical, lignosulfonate, has been used to stabilize high plastic clay, and its performance has been evaluated under static and cyclic loading for different parameters. Test results indicated a significant increase in the unconfined compressive strength under static loading and reduction in axial strains and rate of axial strain development under cyclic loading for stabilized soil specimens. The reductions in rate of axial strain development for stabilized specimens indicate a slow rutting of subgrade soil and hence increase in the longevity of traffic infrastructures. Based on the variation of unconfined compressive strength of treated soil with lignosulfonate contents and curing time, a novel three-parameter compressive strength model was developed as a function of lignosulfonate to water content ratio and time. Also, a power model was used to illustrate the rate of strain development for both treated and untreated specimens under cyclic loading, and model constants were evaluated at different confining pressures.

Automated summary

In this study, lignosulfonate was used as a stabilizer for high plastic clay to improve strength and durability of soil specimens. Under static loading, there was a significant increase in unconfined compressive strength, while under cyclic loading, reductions in axial strains and rate of axial strain development were observed for the stabilized soil specimens.