USING CEMENT AND FIBERS AS ADDITIVES FOR LIQUEFACTION MITIGATION OF SANDY SOILS
Keywords:Liquefaction, shear modulus, Cyclic stress, Geofiber
Liquefaction is one of the most significant earthquake-related phenomena that reduce the resistance of saturated loose sandy soils. To minimize the potential for liquefaction, polypropylene fibers, geofibers, and polypropylene fibers with cement were used as stabilization materials. A series of laboratory stress-controlled undrained cyclic triaxial tests has been conducted as per ASTM D3999 and ASTM D5311. Dry sand–cement mixes were prepared using an electric mixer with randomly distributed polypropylene fiber at different percentages of fiber contents. Polypropylene fibers have lengths of 10 mm and 20 mm. Cemented specimens with cement content varying from 0 % to 2 % by weight of dry sand were prepared and cured for 3 days. Geofiber specimens were prepared by placing 6.5 cm diameter geofibers inclusions in various horizontal arrangements in the sample. It was found that the liquefaction improvement factor (LIF) increased when fiber content and fiber length increased. LIF of the addition of 1% polypropylene fibers (PF) of 20 mm was equal to 215.38% at cyclic stress ratio (CSR) = 0.20. The addition of geofibers increased the liquefaction resistance as the number of layers increased. The addition of geofibers increased the liquefaction resistance as the number of layers increased. The addition of 2% cement (C) +1% P.F. provided the best liquefaction resistance in this study compared with other additives. LIF of samples reinforced with 2% C+1% PF equals 893.33% at CSR= 0.30. This study proposes cement and fiber as good soil improvement techniques that can improve liquefaction resistance.