Use of Egg Shell Powder and Periwinkle Shell Ash to Strengthen the Engineering Properties of Clayey Soil

Recently, the stabilization of clayey soil (CS) has drawn the attention of numerous researchers. In the past, Egg Shell Powder (ESP) and Periwinkle Shell Ash (PSA) were individually tested for their ability to stabilize clayey soil. The author has attempted to stabilize the clayey soil by combining the two of them. The goal of the current study was to compare the efficacy of various eggshell powder and periwinkle shell ash concentrations as soil stabilizers. Testing procedures include the California Bearing Ratio (CBR), Atterberg limits, Unconfined Compression Test (UCS), and compaction tests on the mixture of clayey soil, eggshell powder and periwinkle shell ash. In this study, ESP and PSA were used as soil stabilizers. PSA was varied (i.e., 3%, 6%, 9%, 12%) after ESP was fixed at 12% utilizing index properties testing. The current study aims to evaluate the increase in the strength and stability qualities in soft subgrade soil by stabilizing it first with ESP and then reinforcing it with PSA. It was found that curing time, eggshell powder, and periwinkle shell ash concentration all significantly affected the engineering qualities of the stabilized soil. The findings demonstrated that increasing eggshell powder content increased unconfined compression strength and California bearing ratio values up to a certain point and then decreased slightly. On the other hand, the strength attributes described increased as periwinkle shell ash concentration increased. Additionally, it was found that the stabilized soil samples’ strength properties had been significantly improved by the curing period.