Investigation of Strength and California Bearing Ratio Properties of Natural Soils Treated by Calcium Carbide Residue

In this study, calcium carbide residue is used as a binder to treat over-wetted clays being used as embankment filling material in China highway engineering practice. To prepare the treated soil specimen, calcium carbide residue is added in the sampled soil with contents of 4%, 6%, and 8% (dry soil weight basis). For comparison, lime is also used as the binder to treat soils with contents of 4% and 6% (dry soil weight basis). To investigate the performance of treated over-wetted soils, unconfined compression strength (UCS) test, water soaking durability test, and California Bearing Ratio (CBR) test are carried out. The factors controlling the aforementioned mechanical properties of treated soils are discussed. From the tests, it is found that calcium carbide residue treated soils have better performance than that of lime treated soils. It is concluded that calcium carbide residue can be adopted as an alternative binder to treat over-wetted soils being used as highway embankment filling materials.