A Review on Stabilization of Soil Using Bio-Enzyme

Journal of emerging technologies and innovative research, 2021

Lithomargic clay constitutes an important group of residual soils, commonly found in the western coastal side (konkan region) of southern India. Most of the area in konkan hence have a tough time due to landslide and debris fall during the monsoon. Lithomargic clay loses a greater part of its strength when saturated. They are generally kaolinitic and contain high percentage of silt deposits which bring in problems like slope failure, foundation failures, embankment failures, uneven settlements etc. A potential treatment method which would improve soil behavior using green technology would be beneficial considering the cost savings and environmental synchronization in comparison to other chemical stabilization methods. The purpose of this study is to understand the effect of bio enzyme treatment on lithomargic clay. Soil stabilization using bioenzyme (Terrazyme) occurs through cationic exchange. A set of lab studies were conducted to study the change in index and strength properties of collected lithomargic clay samples by stabilization with varying dosages of terrazyme enzyme. The optimum dosage of terrazyme was found to be 0.1 ml/L. It is observed, that there is 42%, 70%, 35% increase in unconfined compressive strength, cohesion, and angle of friction respectively after 7 days curing. A series of stability analysis on embankment slope of different heights and slope angles for unstabilized and stabilized soil slope were performed. Factor of safety for slopes of varying heights (4m to 12m) and slope angles (30º to 60º) where greater than 1.5 for the stabilized soil.

The abundantly available lateritic soil in Dakshina Kannada and Udupi districts does not satisfy the requirements (Liquid Limit ≤25% and Plasticity Index ≤6 %) to be used as a base course material in pavements. In order to improve its properties the soil is blended with sand at different proportions unless until it satisfies the Atterberg's Limits for sub-base course. In recent past many Bio-Enzymes have come to the market which can be used as stabilizing agent. One such stabilizing agent is TerraZyme, which is used in the present investigation to further stabilize blended soil. The effect of enzyme on soil and blended soil in terms of Unconfined Compressive Strength (UCC), California Bearing Ratio (CBR), Compaction and permeability are studied. It has been observed that the enzyme treated soil showed significant improvement in terms of UCC, CBR with longer curing period.

2020

1,2,3,4UG Student, Dept. of Civil Engineering, Anjuman Institute of Technology and Management Bhatkal, Karnataka, India 5Assistant Professor, Dept. of Civil Engineering, Anjuman Institute of Technology and Management Bhatkal, Karnataka, India ---------------------------------------------------------------------***---------------------------------------------------------------------Abstract Soil is a naturally occurring material used for the construction of all except the surface layers of pavements. Soil stabilization is the alteration of soils to enhance their properties. Stabilization of soil includes various techniques for modifying the properties of a soil to improve its engineering performance at a desired level. Various stabilizers have emerged into the civil engineering field and stabilization by Bio-enzymes is one among them. Shedi soil is the name given to the locally available whitish, pinkish or yellowish silty sand. The Shedi soil is an expansive soil and has great affin...

2005

This research studied the effect of two enzymes as soil stabilizers on two soil types to determine how and under what conditions they function. Researchers evaluated the chemical composition, mode of action, resilient modulus, and shear strength to determine the effects of the enzymes A and B on the soils I and II. The enzymes produced a high concentration of protein and observations suggest the enzymes behave like a surfactant, which effects its stabilization performance. The specimens were subjected to testing of varying lengths of time to determine their performance. Researchers observed an increase in the resilient modulus as the curing time increased but that an increase in application rate, as suggested by manufacturers, did not improve the performance of the enzymes. The study also suggests noticeable differences between the two enzymes and their effects on the soils in terms of resilient modulus and the stiffness of the soil.

Engineers often face the problem of constructing facilities on or with soils, which do not posses sufficient strength to support the loads imposed upon them either during construction or during the service life of the structure. Vast areas of India consist of Black Cotton Soil which has high clay content, low strength and minimal bearing capacity. The poor engineering performance of such soils has forced Engineers device cost effective and ecofriendly methods for improving the engineering properties of poor soils. As the conventional soil stabilizers like gravel, sand, etc. are depleting and becoming expensive day by day at a very rapid pace, it becomes necessary to look towards for alternative ecofriendly stabilizers as their substitute. Recently many Bio-enzymes have emerged as cost effective stabilizers for soil stabilization. One such bio-enzyme, Terrazyme, has been used in the present work to study its effect on the Unconfined Compressive strength of the Black Cotton soil. It has been found that Terrazyme treated Black Cotton soil shows significant increase in Unconfined Compressive strength with longer curing period.

In India vast area is occupied by black cotton soil mainly contains clay as chief constituent. They show minimal bearing capacity and low strength. These soils swell when comes in contact with water and shrink as they dry out. Engineers face problems with such type of soils, which do not posses sufficient strength to carry the imposed loads during construction and the life of the structure. Properties of the soil must be increased to achieve economy and to improve the performance of structure. Soil stabilization is the process of reducing undesirable behaviour of expansive soils. Conventional stabilization methods are time consuming and are proved to be not economical, it become necessary to look for alternative eco-friendly stabilizers like bio-enzymes. Different types of bio-enzymes available for soil stabilization are Renolith, Permazyme, Terrazyme and Fujibeton. The present study deals the effect of Terrazyme a bio-enzyme on shear strength and CBR value of expansive soil. Laboratory tests were conducted on various dosages, stabilizer was added by replacing 1, 2, 3 and 4 percentages of the optimum water content of the black cotton soil.

IRJET, 2022

Engineers often face problem related to soil properties like its bearing capacity. Sometimes engineers face problem that the project site isn't capable of retaining the load of the structure, either at the time of building the structure or after construction or during lifespan of the structure. To deal with such a problem soil stabilization is done or to enhance the property of soil for safety of structure and to increase bearing capacity. To deal with these problems in ecological, eco-friendly and cost-effective way soil stabilization with bioenzyme is applied. As the conventional soil stabilization done by Gravel, sand etc. are not very much effective and is costly now a days. Recently many bio-enzymes have been tested and used for soil stabilization economically. Terrazyme is one such bio-enzyme which has been used in the present project to determine its impact on CBR values and consistency limits of soil. It has been found that Terrazyme treated soil shows significant increase in the consistency limits and CBR values with the longer curing period.

International Journal for Research in Applied Science & Engineering Technology (IJRASET), 2020

In India the construction work is gaining huge demand. This forces the engineers to carry out the construction in unstable soils like black cotton soil or the expansive soil as India consists of vast area occupied by black cotton soil mainly contains clay as chief constituent. They show minimal bearing capacity and low strength. These soils swell when comes in contact with water and shrink as they dry out. Engineers face problems with such type of soils, which do not posses sufficient strength to carry the imposed loads during construction and the life of the structure. Properties of the soil must be increased to achieve economy and to improve the performance of structure. Soil stabilization is the process of reducing undesirable behavior of expansive soils. Conventional stabilization methods are time consuming and are proved to be not economical, it become necessary to look for alternative eco-friendly stabilizers like bio-enzymes. Different types of bio-enzymes available for soil stabilization are Renolith, Permazyme, Terrazyme and Fujibeton. Bio-Enzyme namely Terrazyme has been used as stabilizer in this work. The locally available expansive soil was accumulated from field to study the geotechnical properties. The plasticity index is much more due to the high percentage of clay content in this type of soil. Various tests were carried out for the virgin soil and bio enzyme treated soils with variable dosages. The tests carried out were the consistency limits, compaction properties, and California bearing ratio. The aim of this study is to utilize bio enzyme to improve the engineering properties of expansive soil and to increase the compressive strength and CBR value of the compacted expansive soil.

IRJET, 2020

Soil is a naturally occurring material used for the construction of all except the surface layers of pavements. Soil stabilization is the alteration of soils to enhance their properties. Stabilization of soil includes various techniques for modifying the properties of a soil to improve its engineering performance at a desired level. Various stabilizers have emerged into the civil engineering field and stabilization by Bio-enzymes is one among them. Shedi soil is the name given to the locally available whitish, pinkish or yellowish silty sand. The Shedi soil is an expansive soil and has great affinity towards water. Hence there is a need for improvement of these properties of soil when they are used for construction. The present study is undertaken to evaluate the effectiveness of different dosages of Bio-enzyme as soil stabilizers. For the present study, Bio-enzyme was prepared by using different chemicals compounds and the same is used for stabilization. Locally available Shedi soil with varying index properties were mixed with different enzyme dosages namely, 200ml/3m 3 , 200ml/2.5m 3 , 200ml/2m 3 and 200ml/1.5m 3 and kept for 0, 7, 15 and 30 days curing period to determine the changes in the geotechnical properties of Shedi soil. The obtained results were analysed and investigated in terms of consistency, compaction and unconfined compressive strength (UCS). Analysis of the test results shows that stabilization of Shedi soil by Bio-enzyme improves geotechnical properties of soil up to great extent for the dosage of 200ml/3m 3 .

Rural Connectivity becomes a critical component in the socioeconomic development of rural people by providing access to amenities like education, health, marketing etc. It has been established that investments in rural roads lifts rural people above the poverty line. The evidence also indicates that as the rural connectivity improves, the rural poverty levels come down. Economy of the nation is reliant on road infrastructure for which the roads should be intended to meet the steadily changing burdens and environment. Economy of the nation is reliant on road infrastructure for which the roads should be intended to meet the steadily changing burdens and environment. Attributable to boom in vehicle development, vehicle load on our road is expanding quickly which requests for good nature of subgrade from economical design perspective. It turns out to be expensive to utilize soil having subgrade with low CBR worth to endure heavy loaded weight of vehicles, these requires the interest for enhancing the quality of subgrade utilizing stabilizers to enhance the CBR values, so that less thickness of asphalt can be designed with no bargain with quality of asphalt development. Bio-enzyme is a natural, non toxic, non flammable, non-corrosive liquid enzyme formulation fermentedfrom vegetable extracts that improves the engineering qualities of soil, facilitates higher soil compaction densities and increases stability. Enzyme catalyze the reactions between the clay and the organic cat-ions and accelerate the cat-ionic exchange process to reduce adsorbed layer thickness. For other types of chemical stabilization, chemicals are mixed with soil, which is difficult to mix thoroughly, but bio-enzyme is easy to use as it can be mixed with water at optimum moisture content and then it is sprayed over soil and compacted In recent past many Bio-Enzymes have come to the market which can be used as stabilizing agent. One such stabilizing agent is TerraZyme, which is used in the present investigation to further stabilize blended soil.Bio-enzymes available for soil stabilization such as renolith, Perma-Zyme, Terra-Zyme, Fujibeton etc. These enzymes have been proven to be very effective and economical. Another advantage of the bio-enzyme is that these are environment friendly. When these bio-enzymes are mixed with soil they alter its engineering properties UCC, CBR with longer curing period