This research examines the feasibility of partially replacing lime with eggshell powder (ESP), a low-cost, abundant, and environmentally friendly by-product, in stabilizing dredged clay. Direct shear (DS) and unconfined compressive strength (UCS) tests were performed on samples with 8% lime and varying ESP contents (0–20%), cured for 3 h, 7 d, and 28 d. The DS test results showed that shear strength, cohesion, and internal friction angle all increased with longer curing time and higher ESP content up to 15%. Beyond that point, these properties declined, indicating that 5% ESP is the optimal content. The USC test results showed that UCS increases with extended curing time, while exhibiting an initial increase followed by a decrease as the ESP content rises, reaching a peak at the optimal dosage of 15%. After 28 d of curing, the dredged soil treated with 15% ESP and 8% lime achieved an UCS of 166.3 kPa, about 18.5 times that of the untreated soil. These results indicate that the combined treatment of ESP and lime significantly enhances the strength properties of dredged clay, providing a sustainable approach for recycling eggshell while improving the engineering performance of dredged soil in construction applications.
Chen et al. (2025) studied this question.