Strength and Volume Change Characteristics of Clayey Soils: Performance Evaluation of Enzymes

Abstract

This study was conducted to evaluate the strength and volume change characteristics of a sedimentary residual soil mixed with bentonite (S1) when treated with three different enzymes. In addition, three reference clays including bentonite, illite, and kaolinite were also treated with enzymes to study the effect on their strength characteristics. Soil samples prepared at the optimum moisture content (OMC) were sealed and cured for four months. After curing, reference clays were tested for unconfined compressive strength (UCS). For swell tests, the S1 soil samples were placed on porous stones, which were immersed in water to allow capillary soaking of the samples. S1 samples were allowed to dry at ambient temperature for shrinkage test until the rate of reduction in volume became negligible. On completion of swell tests, the samples were tested for UCS to determine the decrease in strength due to saturation. No increase in strength and decrease in volume change were observed for any of the enzymes and dosages. Field Emission Scanning Electron Microscope (FESEM) showed some dense packing of particles for treated samples, whereas X-ray diffraction (XRD) did not reveal any change; in fact, the pattern for untreated and treated soil samples were indistinguishable.

Potential of Soil Stabilization Using Ground Granulated Blast Furnace Slag (GGBFS) and Fly Ash via Geopolymerization Method: A Review

“…Clayey soils are seen as a potential natural hazard capable of wreaking havoc on engineering buildings [ 9 , 10 ]. Additionally, structures constructed on clayey soils have incurred significant damage as a result of the clayey soil’s undesirable and unpredictable characteristics [ 11 , 12 , 13 ].…”

Evaluation on the Mechanical Properties of Ground Granulated Blast Slag (GGBS) and Fly Ash Stabilized Soil via Geopolymer Process

“…Clay soil, with its low strength and stiffness, may cause damage to the foundation of buildings and cracks along the road pavement. Thus, it poses a challenge for experts and companies engaged in civil engineering [ 5 , 6 ]. In addition, clay soil is considered a potential hazard that inflicts severe damage to the engineering structure [ 6 , 7 ].…”

“…Furthermore, structures built on clay soils are subjected to extensive damages due to the adverse and unpredictable characteristics of the soil [ 4 , 5 , 6 , 7 , 8 ]. Usually, the soil will shrink with the reduction of moisture content and swell with the increase in moisture content [ 8 , 9 ].…”

“…Clay soil has high plasticity, low support, and high shrinkage when the soil contains water [ 9 , 10 ]. This condition encouraged civil engineers to seek solutions in order to strengthen the soil through soil stabilization [ 3 , 4 , 5 , 6 , 7 , 8 , 9 , 10 , 11 , 12 , 13 ]. Soil stabilization aims to increase the mechanical properties of the soil and also to control plasticity and shrinkage in soils containing excess water [ 4 , 8 , 9 , 10 ].…”

“…Soil stabilization aims to increase the mechanical properties of the soil and also to control plasticity and shrinkage in soils containing excess water [ 4 , 8 , 9 , 10 ]. In order to successfully withstand superstructure loads, soil stabilization techniques are essential to ascertain the excellent stability of soil [ 6 , 9 , 10 ].…”