USE OF DRY MIXING METHOD IN FLY ASH BASED GEOPOLYMER AS A STABILIZER FOR DREDGED SOIL
Keywords:Fly ash, Geopolymer, Soil stabilization, California bearing ratio, Unconfined compressive strength
This study aims to improve the properties of dredged soil obtained from a river in the Philippines.
Different percentages of fly-ash based geopolymer, namely 10%, 20%, 30% were used using a dry mixing
method to determine the optimum mix. The procedures based on the ASTM standards were conducted to
determine the index properties namely Grain Size Distribution Curve (ASTM D422), Specific Gravity (ASTM
D854), Atterberg’s Limits (D4318), and CBR Test (ASTM D1833) and UCS test (ASTM D2166) of untreated
soil. While only the California Bearing Ratio Test and UCS test were conducted on the treated soil. The
experimental results showed that the fly-ash based geopolymer improved both the CBR index and the
Unconfined Compression Strength of the dredged soil. The optimum mix for the soil-geopolymer mix was
30% because it displayed the largest increase in the CBR index (50.23%) and Unconfined Compressive
Strength (912.88 Kpa).