Banana Fibre-Reinforcement of a Soil Stabilized with Sodium Silicate

Many unsuitable soils for construction purposes can be made suitable by using unconventional soil stabilizers. This study investigates the effects of banana fibre-reinforcement of a soil stabilized with sodium silicate on the geotechnical properties of the composite. It involved the application of 1% sodium silicate with varying proportion (0.1, 0.2, 0.3, 0.4 and 0.5%) of banana fibre to a gravelly sand. Index properties, unconfined compression, direct shear, split-tensile and California bearing ratio (CBR) tests were determined for the stabilized soil and the reinforced soil samples. The results show that the plasticity index, unconfined compressive strength (UCS), shear strength, split-tensile strength and CBR of the specimens stabilized with sodium silicate increased with increasing percentage of banana fibre content. The application of 0.5% banana fibre strengthened the soil - the UCS increased by 445%, shear strength by 80%, split tensile strength by 194% and the soaked CBR increased by 1083%. The banana fibre-reinforcement of the sodium silicate stabilized sandy soils made the stabilized soil become suitable for road pavement application as sub-base material.