Strength Of Black Cotton Soil Research Articles

Improving Shear Strength and Microstructural Behavior of Black Cotton Soil Treated with Construction Demolished Waste

With its expansive character and low bearing capacity, black cotton soil presents considerable obstacles to construction projects. These challenges can be difficult to overcome. There is a tendency for it to rise and compress in response to variations in the amount of moisture present, and it also has weak strength properties, which makes construction activities more difficult. This study explores the possibility of stabilizing black cotton soil with recycled construction and demolition (C&D) waste in order to address these issues. Various C&D waste materials, like concrete, bricks, mortar, and other debris, are examined for their potential to enhance the shear strength of black cotton soil. The paper assesses the effectiveness of incorporating C&D waste blends ranging from 5% to 25% to mitigate soil swelling and shrinkage with improve shear strength. Previous to determining the soil's shear strength, index properties were assessed. Unconfined compression strength tests (UCS) are carried out on compacted specimens handled with C&D waste blends, with curing periods of 1 day, 7 days, and 28 days at room temperature. A comparison investigation showed that there was a comparable increase in UCS and a decrease in axial strain at failure as the amount of C&D waste in the soil rose. Micro-analyses displayed that the main factors prompting the interacting behavior of soil amended with C&D waste include changes in the gradation, cohesiveness, and the interplay between the particles, the mineralogical makeup, and the elemental, chemical, and microstructural components. The research aims to offer insights into sustainable methods for strengthening the performance of black cotton soil while reducing waste generation in construction activities.

Performance Evaluation of Coal Gangue-GGBS–Based Geopolymer for Treating Black Cotton Soil

Abstract Black cotton soils are extremely problematic because they are susceptible to large volume changes with variation in moisture contents. These soils are conventionally stabilized with ordinary portland cement and lime, but the production/utilization of these traditional stabilizers is highly energy intensive, involves quarrying, and emits large quantities of carbon dioxide (CO2) into the atmosphere. Geopolymer is a promising alternative to these stabilizers because it provides high strength, consumes low energy, and emits low CO2 during synthesis and application. In this study, geopolymers synthesized from coal gangue (waste generated during coal mining) and ground granulated blast furnace slag (GGBS; by-product from the iron and steel industry) binders were evaluated for treating black cotton soil. A mixture of sodium silicate and sodium hydroxide is used as an alkaline activator solution for geopolymerization. An attempt is further made to identify the optimal dosages of geopolymer by evaluating the strength and durability characteristics of geopolymer-treated black cotton soil mixtures. X-ray diffraction and scanning electron microscopy were further conducted to distinguish the mineralogical and microstructural changes that occurred because of geopolymerization. From this study, it is found that using coal gangue alone as a precursor in geopolymer is good at improving the strength of black cotton soil but observed to be weak in durability. Hence, an attempt is further made to synthesize a better-performing geopolymer with a combination of GGBS and coal gangue, i.e., effective in both strength and durability aspects. Optimal geopolymer identified in this study can be a sustainable alternative to traditional stabilizers in improving black cotton soils for geotechnical subgrade applications.

Strength Improvement of Black Cotton Soil Using Plastic Bottles and Crushed Glass Wastes

The aim of this study was to improve the strength of black cotton soil for its suitability for road subgrade construction using wastes from plastic bottles and glass waste powders. Currently, nondecomposable wastes from plastic and glasses have become threats to the human health and the environment. This study used the wastes to replace cement, since the cost of cement raised due to energy and raw material to use as stabilizer in weak soil. The glass powder (WGP) and the plastic chips were mixed with the soil sample with a percentage by dry weight of 6%, 12%, 18%, and 24% of WGP and 2%, 4%, 6%, and 8% of plastic chips, respectively. The glass waste can be prepared similar to the soil as the requirement of test standards and plastic wastes was used as reinforcement for the soil-glass-mix; hence, its purpose was geomechanical. Laboratory tests for soil-mix physical properties and strength parameters were conducted. Soil laboratory test results proved that the natural soils were classified to A-7-5 as per the AASHTO Soil Classification System and CH as per the Unified Soil Classification System (USCS). The Unconfined Compressive Strength (UCS) improved from 91.92 kPa to 688.83 kPa, and the California Bearing Ratio (CBR) improved from 2.64 to 17.5. The improvement of subgrade soil properties was increased with increased ratios of powder glass and plastic strips. The result indicated that the two stabilizers were very effective in improving strength parameters and index parameters.

Effect of Bioprecipitation and Ferrochrome Ash Stabilization on the Strength of Black Cotton Soil

Effect of Bioprecipitation and Ferrochrome Ash Stabilization on the Strength of Black Cotton Soil

Influence of Salt Permeants on The Swelling and Strength Behavior of Fibre Treated Black Cotton Soil

Due to the limited availability of the bentonite in India, this investigation was initiated to check the suitability of using black cotton (BC) soil for liner application. Since, the waste tires, which are a major environmental concern, is mixed with the balck cotton soil as reinforcement material to reduce the desiccation cracks caused by shrinkage of the soil. As the salts present in leachate alter the liner material's geotechnical properties, the tire fibre mixed black cotton soil were tested for swelling and strength in the presence of various concentration of NaCl and CaCl2 salts. For this investigation, three different percentages of tire fibres (5, 10, and 15%) and two concentrations of salt permeants (i.e., 0.1 and 1N) were selected. The result indicated a reduction in the swelling and strength of BC soil with the addition of tire fibres. This reduction becomes pronounced with the higher concentration of various permeant salts. The swelling time of fibre-treated soils is reduced with the rise in concentrations from the time-swell relationship. According to unconfined compressive strength (UCS) test data, the ductile behaviour of soil sample increased with addition of fibre content. Finally, results suggested that the acceptance of tire fibre content for liner application is up to 10%, including different salt effects.

Use of Recycled Construction and Demolition (C&D) Wastes in Soil Stabilization

With the growing construction sector, there is a constant rise in wastes generated by both construction and demolition activities. According to an estimate by Building Material Promotion Council (BMPTC), 150 million tonnes of construction and demolition (C&D) wastes are generated in India annually. However, the official recycling capacity is a meagre6, 500 tonnes per day (TPD) - just about 1 percent. This paper examines the properties of Black cotton soil and investigates the use of recycled C&D wastes in soil stabilization of black cotton soil. This research focuses on the inexpensive and eco-friendly nature of C&D wastes as an admixture for soil stabilization. The tests were performed using different proportions of recycled C&D wastes in the proportions: 5%, 10%, 15%, 20%, and 25%, to increase the strength of black cotton soil. California Bearing Ratio (CBR) showed an increase from 2% to 18.09%, Maximum Dry Density (MDD) showed a decrease from 2.107 g.cc-1 to 1.69 g.cc-1, and Optimum Moisture Content (OMC) showed a variation and increased from 15% to 18.09% with the addition of 25% C&D wastes.

Efficiency of cement and lime in stabilizing the black cotton soil

Black Cotton soil is a extremely problematic and sensitive to climatic changes. Due to the moisture content, the strength reduction in black cotton soil will be heavy. Stabilization is one of the conventional and extensively used processes to increase the engineering properties of soil. The investigation was carried out to study the increase in strength of black cotton soil using lime and cement. The experimental works were carried out using different proportions of lime (1%, 2% and 3%) and cement (2% and 4%). The Proctor Compaction Test and California Bearing Ratio were conducted to determine the exact proportion of additive at which the strength of Black Cotton soil will increase. The observed results from the compaction test revealed that the maximum dry density of soil increased by adding lime up to 2% due to the cementitious bond; further addition of lime led to a decrease. Also, the mixture of 2% cement with lime blended soils led to an increase in dry density due to the cementation action, which reduced the plasticity of soil, and when it exceeded 2% of cement, the density decreased. The percentage increase in the soil strength after adding additive was 76.54%. These results indicated that the lime, cement or a combination of both reacted as a good additive to stabilize the soil.

Black Cotton Soil Stabilization by Using Fly Ash - Kota Stone Slurry Mix

Abstract: The usage of waste material for stabilizing black cotton soil has been a sustainable interest. Kota stone slurry is a waste from kota stone and fly ash is a waste from industries containing high amount of sodium and magnesium, was used as a soil stabilizer for blac cotton soil improvement in this study. This research investigated the effects of sizes and percentages of kota stone slurry mix and fly ash on the physical and strength properties, which included particle size distribution, Atterberg limits, compaction, and unconfined compressive strength (UCS) of blac cotton soil. Micro structural characterization, including the scanning electron microscopic, energy dispersive X-ray spectroscopy, and X-ray diffraction was conducted on both untreated and treated black cotton soil samples to examine the mechanism of strength development. The addition of kota stone slurry and fly ash reduced the water holding capacity, which then caused the reduction in soil plasticity (from 18 to 11%) and optimum water content (from 20 to 16%) along with the increase in peak dry density (from 1.66 to 1.74 Mg/m3). The strength of black cotton soil may increased from 50 to almost 220 kPa. The optimum kota stone slurry and fly ash contents, providing the highest UCS, were at 20 and 30% for 0.063 mm kota stone slurry and fly ash and 0.15 mm kota stone slurry and fly ash, respectively. The UCS improvement of treated marine clay is attributed to the formation of cementation compounds, mainly aluminum magnesium silicate hydrate (A–M–S–H). The outcome of this research will allow the use of RBT as a low-carbon soil stabilizer across civil engineering applications. Keywords: Stablization, Fly ash, kota stone slurry, Atterberg limits, Compaction, and unconfined compressive strength

Influence of Lime for Enhancing Characteristics of Expansive Soils in Road Works

Expansive soils are found in black cotton soils, which swell or shrink in volume when presented to changes in moisture content. Lime treatment is exhaustively used to increment the properties of sensitive and fragile soils. One of the hugest clarifications behind using lime is to decline the developing presentation of the earth soil. The arrangement of extra safeguards improves the reaction of quicklime (CaO) with water, structures hydrated (slaked) lime (Ca (OH)2), and thus earth characteristics. The vast inadequacy of employing lime is growing the deficiency of lime offset earth. Following that, the goal of this study is to see how re-establishing time affects the geotechnical qualities of settled Black cotton soils with lime. These discoveries recommend that adding Lime as a stabilizer works on the strength of black cotton soil. Some of the characteristics of the soil likely to be increased by using stabilizer in this work are UCS (Unconfined Compressive Strength) at different curing periods (7,14,28 and 56 days), CBR (California Bearing Ratio) value at unsoaked and soaked and MDD (Maximum Dry Density) decrease at different lime percentages(%) like 2.4.6.8 and 10. The result showed here untreated soil got stabilized by using the stabilizer in certain extent In this adjustment various rates of cementitious material is added to black cotton soil and directed tests like plasticity, compaction, swell pressure, free swell index(FSI), Coefficient of permeability (k) and CBR(soaked and unsoaked) at various conditions like OMC,OMC+2% water and OMC+5% water, UCS (Unconfined Compressive Strength) was performed. From the test results, it is identified that the stabilization agent decreases plasticity and improves strength characteristics. Addition of stabilizing agent makes the black cotton soil to non-plastic, non-swelling and attains increase CBR values which are greater than 25% for a dosage of 10% lime at OMC but remaining OMC+2%water & OMC+5%water CBR values are not various much difference as per test results. With the addition of lime, the black cotton soil becomes non-plastic, non-swelling, and has high strengths. Treated soils are used as a development material, for example, a subgrade layer in the development of adaptable asphalt pavements for roads.

Effect of Water Content on Shear Strength of Black Cotton Soil

The bearing capacity of the soil is an important factor in the process of designing foundations on soil and it depends upon shear strength parameters C and Phi. The large part of the Maharashtra state is having black cotton soil which is vulnerable because of the fluctuation in water content in it. Due to the expansion and contraction property of black cotton soil, the shear strength varies with variation of water content. This research, it is focused to find the effect of moisture content on the shear strength of black cotton soil. The undisturbed samples of black cotton soil are explored from the site from desirable depth using the drilling machine. On explored samples, various field and laboratory tests are performed to find the strength parameters of the soil at different water content. This study gives different values of shear strength in black cotton soil with variation in moisture content. From the work, it has been seen that there is increase in the shear strength in the initial stage as water content an increased, later increase in the water content causes a decrease in the shear strength of black cotton soil. It indicates that, optimum water content should be maintained in the foundation soil to avoid excess settlement of foundations in soil.

Utilisation of Recycled Glass Powder for the Stabilization of Black Cotton soil by Alkali Activation

Black Cotton Soil forms a major soil group in India. It covers 20% of the total area of India. Due to its high swelling and shrinkage characteristics, Black cotton soil has been challenging for construction activities. To overcome the problems caused by black cotton soil, the soil needs to be stabilized. Stabilization increases the strength of soil and controls the swell and shrinks potential of soil thus improving the load bearing capacity of soil. Lime and Cement are commonly used additives in soil stabilization. The production of commonly used additives like lime and cement contributes to a higher carbon footprint. Recycled glass powder is a construction and demolition waste. Recycled glass powder is rich in Silica and Alumina, thereby on addition of an alkali; it forms a geopolymer that enhances the strength of the soil. In this study Recycled glass powder is added in the proportions of 0%, 3%, 6%, 9%, 12%, 15% and 18 % along with Sodium Hydroxide and Sodium Silicate in the ratio of 1:2.5 to the Black cotton soil to facilitate the geopolymerization reaction. The effect of Recycled glass powder based geopolymer on the strength of Black cotton soil for the curing period of 3 and 7 days is investigated. The Unconfined compressive strength of Black cotton soil increases with the increase in proportion of geopolymer up to an optimum value of 9%. With the increase in curing time the strength of Stabilized Black cotton soil increases. A Recycled glass powder based geopolymer can be used as an effective soil stabilizer.

Unconfined Compressive Strength of Black Cotton Soil Mixed with Cement and Polypropylene Fibre

Unconfined Compressive Strength of Black Cotton Soil Mixed with Cement and Polypropylene Fibre

Improvement of Strength of Locally Available Soils using Microbial Induced Calcite Precipitation

Engineering properties of soils are improved by adopting various proven methods such as mechanical and chemical. Strength of locally available soil (Black cotton soil and red soil) was enhanced by application of Microbial Induced Calcite Precipitation (MICP) using species of Bacillus pasteurii. Microbial culture improves the unconfined compressive strength and shear strength of locally available soil. Microbial culture developed from Bacillus pasteurii, was used to stimulate and catalyze the process of calcite precipitation triggered by urea hydrolysis which includes reaction between urea and calcium chloride. This paper includes outcomes of effectiveness of MICP on locally available soil, on three parameters measure of the cementation reagent, measure of Bacillus pasteurii and duration of treatment process. The results elaborated that with the application of MICP, unconfined compressive strength of black cotton soil increased 1.6 to 2.3 times and red soil from 1.8 to 3 times. This gives optimum quantity of microbes and concentration of Cementation reagent as additive to improve strength of black cotton soil and red soil.

Long-term Performance Studies on Strength Characteristics of Black Cotton Soil Reinforced with Untreated and Treated Coir Fibre

Strength retention on the long run can be improved by making coir fibres less water absorbent. In the present study, coir fibres have been alkali treated and admixed in black cotton soil. Use of untreated and treated coir fibres (UCF and TCF) to black cotton soil is comparatively investigated in terms of UCS using remoulded specimens compacted with wide range of dry densities and water contents on the basis of compaction test. Long-term performance is evaluated by curing the remoulded specimens for periods ranging from 0 to 360 days. The test results indicated that the strength of black cotton soil reinforced with UCF and TCF is significantly affected by fibre content, dry density and water content and changes the failure behaviour from brittle to ductile. Long-term performance can be significantly improved by using treated coir fibres, in which the reduction in strength of black cotton soil admixed with treated coir fibres indicated marginal loss of strength, at around 21.16%.

Effect of Reclaimed Asphalt Pavement Stabilization on the Microstructure and Strength of Black Cotton Soil

Effect of Reclaimed Asphalt Pavement Stabilization on the Microstructure and Strength of Black Cotton Soil

Resilient modulus of black cotton soil

Resilient modulus (MR) values of pavement layers are the basic input parameters for the design of pavements with multiple layers in the current mechanistic empirical pavement design guidelines. As the laboratory determination of resilient modulus is costly, time consuming and cumbersome, several empirical models are developed for the prediction of resilient modulus for different regions of the world based on the database of resilient modulus values of local soils. For use of these relationships there is a need to verify the suitability of these models for local conditions. Expansive clay called black cotton soil (BC soil) is found in several parts of India and is characterized by low strength and high compressibility. This soil shows swell – shrink behaviour upon wetting and drying and are problematic. The BC soil shows collapse behaviour on soaking and therefore the strength of the soil needs to be improved. Additive stabilization is found to be very effective in stabilizing black cotton soils and generally lime is used to improve the strength and durability of the black cotton soil. In this paper, the results of repeated load tests on black cotton soil samples for the determination of MR under soaked and unsoaked conditions at a relative compaction levels of 100% and 95% of both standard and modified proctor conditions are reported. The results indicate that the black cotton soil fails to meet the density requirement of the subgrade soil and shows collapse behaviour under soaked condition. To overcome this, lime is added as an additive to improve the strength of black cotton soil and repeated load tests were performed as per AASHTO T 307 - 99 for MR determination. The results have shown that the samples are stable under modified proctor condition with MR values ranging from 36MPa to 388MPa for a lime content of 2.5% and curing period ranging from 7 to 28 days. Also, it is observed that, the CBR based resilient modulus is not in agreement with the laboratory based MR value and therefore it is necessary to use the laboratory determined MR or MR predicted from an appropriate prediction equation for pavement design. An attempt is also made to develop an empirical model for the prediction of MR of lime stabilized black cotton soil. There is a good agreement between the predicted and laboratory MR values with an error of 12%.

Experimental Investigation on the Effect of HDPE Fibres on the Subgrade Strength of Black Cotton Soil

Experimental Investigation on the Effect of HDPE Fibres on the Subgrade Strength of Black Cotton Soil

Influence of fly ash, ground-granulated blast furnace slag and lime on unconfined compressive strength of black cotton soil

Utilisation of industrial waste products with black cotton soil (BCS) in the improvement of its engineering properties has gained attention to the sustainability of the natural resources and cost efficiency. This paper evaluates the influence of fly ash, ground-granulated blast furnace slag and lime at 12%, 8% and 1–9%, respectively, on BCS obtained from the N4 road North West Province, South Africa, to improve the soil. The performance of the modified BCS cured for 7, 28, 60 and 90 days was evaluated using compaction, California bearing ratio (CBR) and unconfined compressive strength (UCS) test according to standard specifications. The CBR value increases with increase in the level of compaction. The influence of the waste materials added for different compaction levels and curing periods improved the CBR and UCS values significantly. UCS of the stabilised BCS meets with the specification for sub-base material at 97% and 100% compaction for all the curing periods.

Role of moulding water content in lime stabilisation of soil

The role of moulding water content, from the dry side of the optimum to the wet side of optimum, in the strength development in lime-treated soils was investigated in the present study. During compaction, the structure of clay particles can change from a flocculated to a dispersed structure as the water content is increased from the dry side of optimum to the wet side of optimum. For efficient formation of pozzolanic compounds, the water content of the soil–lime mixture should be kept as high as possible. The improvement in the strength of Indian black cotton soil treated with different amounts of lime content at different water contents and cured for varying curing periods was studied. The results clearly showed that the strength of black cotton soil treated with lime content increased better when compacted on the dry side of optimum, the other parameters remaining the same. Further, the optimum lime varied with moulding water content and curing period.

Effect of fly ash on the unconfined compressive strength of black cotton soil

The strength of clayey soil can be altered by the addition of fly ash. Many factors of fly ash, such as reactivity, free lime content and silty nature, influence the strength of soil. This study examines the effect of varying fly ash content (at a constant percentage content of lime) and the effect of varying lime content (at a constant percentage content of fly ash) on the strength of black cotton soil. The study, conducted at constant percentage content of lime on the unconfined compressive strength of black cotton soil, with varying percentages of Neyveli fly ash and Vijayawada fly ash with and without curing, has shown that the effect of fly ash is mainly through pozzolanic reactivity and the silty character of fly ash. For Neyveli fly ash, having good reactivity, the pozzolanic reaction effect overrides the effect arising from its silty nature. For Vijayawada fly ash, having poor reactivity, the effect is similar to that of adding silt. It is noted that only reactive fly ash can increase the unconfined compressive strength of black cotton soil. From this study conducted with varying percentages of lime content it has been shown that at very low lime contents, sufficient strength can be achieved for a soil–reactive fly ash mixture; this cannot be attained for soils without fly ash.