Mechanical Properties of Soft Soil Stabilized with Lime and Volcanic Ash

Abstract

The nature of soft clay was identified from the unconfined compressive strength value through unconfined compressive strength (UCS) testing. Soft soil is improperly used as a construction base soil. The purpose of this study was to determine the increase in unconfined compressive strength and foundation-bearing capacity due to the addition of lime or volcanic ash to soft soil. Soft soil has an undrained shear strength of <25 kPa based on the unconfined compressive strength test. The unconfined compressive strength test was carried out on soil with lime or volcanic ash, each 3 to 12% of the dry soil weight. The highest unconfined compressive strength value was obtained on soil with 6% lime and 9% volcanic ash. The bearing capacity of the foundation on soil stabilized with 6% lime increased 13.7 times, while the bearing capacity of the foundation on soil with the addition of 9% volcanic ash increased the ultimate bearing capacity by 8.7 times the bearing capacity of the foundation on soft soil. The bearing capacity of the foundation on soil stabilized with lime is higher than that of the foundation on soil stabilized with volcanic ash.