Abstract
This study shows that calcium carbonate plays an important role as a cementing agent of soils. The vane shear strength and unconfined compressive strength of sedimentary soils are shown to vary with depth and are strongly dependent on the calcium carbonate content. It was found that an increase in calcium carbonate content caused an increase in soil strength, and that a decrease in soil strength was attributed to the decrease in carbonate content. The cementing effects due to calcium carbonate are quantitatively evaluated in this study. The results show that the increase in soil strength due to calcium carbonate is very high, depending on the type and age of the soils. For example, some alluvial sedimentary soils show an increase in unconfined compressive strength of 64 kPa by an increase of one percent in calcium carbonate.
