Strength Mechanism of a Swelling Soil Improved with Jute Fibers: A Laboratory Treatment.

In this paper, results are reported from a series of laboratory tests conducted on a swelling soil treated with different jute fibers with a twofold objective of reducing their swell characteristics and enhancing their geomechanical properties. The efficacy of passive inclusion of three different jute fibers (i.e., natural, woven, and bitumen coated) in controlling both swell potential and pressure, and improving undrained shear strength and consolidation behavior has been examined. It is observed that the inclusion of jute fibers in the swelling soil expectedly improves both undrained shear strength and CBR value of the treated soil. For instance, the original undrained shear strength improves from 200 kPa to as high as 675 kPa and the original CBR value increases from 3% to a maximum of 7.1%. Similarly, both swell potential and pressure of the treated soil reduced significantly from 4.1% to as low as 1.2% and from 90 kPa to a minimum of 40 kPa, respectively. The improvements in soil properties could be attributed to the reinforcing ability of fibers, which possess a relatively higher tensile strength, in corroboration with the adhesive bond between fibers and soil particles at the micro level. While the former plays an active role in avoiding progression of shear failure, the latter would passively resist the initiation of slip at the soil-fiber interface. Notably, while shear strength of soil generally improves upon addition of jute fibers, inclusion of the bitumen coated fibers has been observed to be more effective than rest. [ABSTRACT FROM AUTHOR]