Stabilization Effect of Volcanic Cohesive Soil "Akaboku" by Using Quicklime
Noritaka ARAMAKI, Hiroshi TERASAKO and Takashi MAEDA
Abstract:This present study is performed in order to understand stabilization effect of volcanic cohesive soil "Akaboku" with quicklime. Volcanic cohesive soil "Akaboku" in north-central Kumamoto prefecture originates from Mt. Aso and Mt. Kujyu. The stabilizer used in this study is quicklime. The added stabilizer is quantified as a percentage to soil dry weight. Cone penetrate tests and unconfined compression tests are performed on quicklime-treated samples. Assessments of the stabilization effect measured in both tests are made through a number of compaction, mixing time, mixing method and curing method. The following conclusions are obtained. (1) The unconfined compression strength of quicklime-treated volcanic cohesive soil increases with reducing remolding influence as avoiding over-compaction of specimens and decreasing mixing time by using machine. (2) In the case of exposing samples before compaction, the unconfined compression strengths and cone indices depend on exposing days without additive amount of quicklime. (3) It is confirmed that the stabilization effect of quicklime-treated soil after fixed days of a combination of exposing and curing is larger than that of curing only in spite of same amount of quicklime additive. (4) It is suggested that cost for soil stabilization can be reduced, if the amount of quicklime additive could be decided following mix proportion test is carried out under the earth working conditions. Key Words:Volcanic cohesive soil, Quicklime, Stabilization effect, Mix proportion, Unconfined compressive strength, Cone index, Curing method, Specimen preparation, Cost reduction