Influence of Solid Waste Oyster Shell Powder on the Physical and Swell–Shrink Properties of Expansive Soils

Abstract

To explore the effects of solid waste oyster shell powder (SWOSP) on the physical and swell–shrink properties of expansive soils, the expansive soil in Ningming, Guangxi province (the classification code of soil is CH), was taken as the research object. A series of tests were carried out on the physical and swell–shrink properties of expansive soil samples with OSP contents of 0%, 3%, 6%, 9%, and 12%. The results show that the incorporation of OSP can effectively enhance the integrity of the soil, change the distribution of the particle size of the expansive soil, and effectively reduce the expansion and contraction of the soil. The free swelling ratio, unloaded swelling ratio, loaded swelling ratio, swelling force, and linear shrinkage rates of the tested soil decreased with increasing OSP content and stabilized when the OSP content was 9%. The research results provide theoretical basic data for the improvement of expansive soil with oyster shell powder and also offer a new approach for green engineering.