Cyclic shear performance of reinforced waste steel slag mixed soil

ObjectiveTo improve the engineering properties of clay and increase the utilization of waste steel slag (SS), Methodsgeogrid reinforcement was employed, followed by direct shear tests, cyclic shear tests, and post-cyclic direct shear tests conducted on steel slag-clay mix, sand-clay mix, and pure clay. The study investigated the strength characteristics, damping ratio, shear stiffness changes, and displacement of the mixed soil reinforcement-soil interface under various conditions, including different steel slag contents, vertical stress, moisture content, and shear amplitudes. ResultsThe test results indicate that steel slag significantly enhances the shear strength of the clay-reinforcement interface, with improvement being more effective than conventional sand-modified clay. The steel slag-clay mixed soil exhibited higher damping ratio and shear stiffness, suggesting better vibration damping and energy dissipation properties. Among the various mixtures, the steel slag-clay mix with 40% steel slag content demonstrated the best shear strength, damping ratio, and shear stiffness. Additionally, the shear strength of the steel slag-clay mixed soil increased after cyclic loading compared to pre-cyclic direct shear conditions. The results also show that moisture content has a more significant impact on shear strength, shear stiffness, and damping ratio than vertical stress and shear amplitude. ConclusionThe steel slag-clay mixed soil exhibits improved damping and energy dissipation properties under cyclic shear loading. The experimental findings provide a theoretical basis for using steel slag as a substitute for sand to improve clay soils.