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Lambert Emeka Ezeajugh - One of the best experts on this subject based on the ideXlab platform.
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the swelling behaviour of lignosulfonate treated Expansive Soil
Proceedings of the Institution of Civil Engineers - Ground Improvement, 2016Co-Authors: Dennis Pere Alazigha, Buddhima Indraratna, Jayan S Vinod, Lambert Emeka EzeajughAbstract:This paper presents results regarding the potential of lignosulfonate (LS) to control the swelling of Expansive Soil. One-dimensional swell tests were performed on untreated and LS-treated remoulded samples of Australian Expansive Soil from the state of Queensland. The test results indicated that LS has significant influence on the swelling behaviour of this Expansive Soil. The results were compared with those of identical cement-treated Soil samples, and it was found that LS could be a economical and environmentally friendly alternative to traditional alkaline additives. In addition, the behaviour of LS-treated specimens during repeated freezing and thawing cycles was measured. The results indicated significant improvement in the percentage mass loss in LS-treated specimens compared with cement-treated specimens. The microstructural analysis of the untreated and the LS-treated samples showed Soil surface area reduction in the treated specimens, which in turn reduced the affinity of the specimens towards ...
Dennis Pere Alazigha - One of the best experts on this subject based on the ideXlab platform.
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mechanisms of stabilization of Expansive Soil with lignosulfonate admixture
Transportation geotechnics, 2018Co-Authors: Dennis Pere Alazigha, Buddhima Indraratna, Jayan S Vinod, Ana HeitorAbstract:Abstract This study investigated and identified the mechanisms by which a remoulded Expansive Soil was modified or altered by a non-traditional admixture, lignosulfonate (LS). To achieve this objective, untreated and LS treated samples of Expansive Soil were examined microscopically using X-ray Diffraction (XRD), a Scanning Electron Microscope coupled with Energy Dispersive Spectroscopy (SEM/EDS), Fourier Transform Infrared (FTIR), Computed Tomography (CT-Scan), Nuclear Magnetic Resonance (NMR), Cation Exchange Capacity (CEC), and the role of Specific Surface Area (SSA). The interest was to identify and compare any physical and chemical changes between the untreated and treated samples and then propose the most likely reaction modes between the admixture and the Soil minerals. The results indicated that the percent swell is intimately related to the amount of water that is adsorbed by the Expansive clay minerals. Furthermore, the amount of moisture in an Expansive Soil is influenced by a small addition of organic (cationic) compound such as LS. The adsorption of LS on the mineral surfaces provided waterproofing effect on Soil due to the hydrophobic nature of LS, which in turn contributed to a decrease in the extent of swelling of the otherwise Expansive Soil. The basal and peripheral adsorption of LS led to smearing and subsequent agglomeration of Soil particles restricting water ingress into the Soil body. In addition, the cationic exchange between the admixture and the Soil particle surfaces (i.e. replacing the negative surfaces on clay lattices) prompted flocculation, which further decreased the Soil’s affinity to water.
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the swelling behaviour of lignosulfonate treated Expansive Soil
Proceedings of the Institution of Civil Engineers - Ground Improvement, 2016Co-Authors: Dennis Pere Alazigha, Buddhima Indraratna, Jayan S Vinod, Lambert Emeka EzeajughAbstract:This paper presents results regarding the potential of lignosulfonate (LS) to control the swelling of Expansive Soil. One-dimensional swell tests were performed on untreated and LS-treated remoulded samples of Australian Expansive Soil from the state of Queensland. The test results indicated that LS has significant influence on the swelling behaviour of this Expansive Soil. The results were compared with those of identical cement-treated Soil samples, and it was found that LS could be a economical and environmentally friendly alternative to traditional alkaline additives. In addition, the behaviour of LS-treated specimens during repeated freezing and thawing cycles was measured. The results indicated significant improvement in the percentage mass loss in LS-treated specimens compared with cement-treated specimens. The microstructural analysis of the untreated and the LS-treated samples showed Soil surface area reduction in the treated specimens, which in turn reduced the affinity of the specimens towards ...
Zimao Peng - One of the best experts on this subject based on the ideXlab platform.
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Surface Crack Development Rules and Shear Strength of Compacted Expansive Soil Due to Dry–Wet Cycles
Geotechnical and Geological Engineering, 2019Co-Authors: Zhen Huang, Bingxu Wei, Lujun Zhang, Wei Chen, Zimao PengAbstract:Expansive Soil is a typical multi-crack Soil, and the stability of Expansive Soil slope is significantly affected by cracks. In this study, pores (particles) and crack image analysis system (PCAS), a crack image processing software was used for the dynamic and quantitative measurement of the development of surface cracks in Expansive Soils with different compaction degree under the condition of dry–wet cycles. Furthermore, the shear strength of Expansive Soil with different degree of crack development was also tested. The test results showed that the greater the compaction degree, the smaller the cracking degree. The cohesion decreased with the increase of dry–wet cycles; however, the internal friction angle was less affected. For the same number of cycles, cohesion increased with the increase of the compaction degree. The relationship between the cohesion and the crack parameters including the number of crack joints, number of cracks, total length of cracks, and average width of cracks exhibited similar trends. This indicates that cohesion has some relevance with these crack parameters. The crack rate and fractal dimension exhibited linear relationship with cohesion. The research results provide an important basis for the application of crack parameters to calculate the strength parameter of Expansive Soil in engineering field.
T. Thyagaraj - One of the best experts on this subject based on the ideXlab platform.
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Lime slurry stabilisation of an Expansive Soil
Geotechnical Engineering, 2020Co-Authors: T. ThyagarajAbstract:Lime slurry and lime pile techniques are viable choices for in-situ stabilisation of Expansive Soil deposits. This paper reports the results of a laboratory study on in-situ chemical stabilisation of an Expansive Soil that permeated lime slurry through an artificially desiccated Expansive Soil specimen. The Soil was desiccated in the laboratory to induce shrinkage cracks in the compacted Expansive Soil. The shrinkage cracks greatly assisted migration of lime slurry in the Expansive Soil mass. The efficiency of lime slurry in chemically stabilising the desiccated Expansive Soil was investigated by comparing the physico-chemical properties and engineering properties of the treated Soil with those of the natural Soil specimen at two radial distances. Experimental results indicated that migration of lime slurry through the desiccated Soil promoted strong lime modification and pozzolanic reactions in the Soilmass. The strong Soil-lime reactions rendered the Soil less plastic, reduced the swell magnitude, and increased the unconfined compressive strength of the lime-slurry treated specimens. Laboratory results indicate that slurry application to Soil deposits with shrinkage is effective, and that it may therefore be preferable to chemically stabilise Soil deposits during the dry season
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Sulfate effects on sulfate-resistant cement–treated Expansive Soil
Bulletin of Engineering Geology and the Environment, 2020Co-Authors: P. Sriram Karthick Raja, T. ThyagarajAbstract:Even though the effectiveness of sulfate-resistant cement (SRC) in stabilizing the high sulfate-bearing Expansive Soils is proven, its effectiveness in controlling the volume change of Expansive Soils when exposed to external sulfate contaminants is not known. The physico-chemical and index properties provide basic insight into the volume change behavior of clays. Therefore, this study brings out the effect of external sulfate contamination on the physico-chemical and index properties of SRC-treated Expansive Soil. Three SRC contents of 5, 10, and 15% were added to the Expansive Soil separately and reconstituted with distilled water and cured for 1–28 days. After the desired curing period, the SRC-treated Expansive Soil was reconstituted with sulfate solutions of 5000, 10,000, and 20,000 ppm separately and moisture equilibrated for 1 day for the determination of the properties. The experimental results showed that the SRC treatment increased the pH from 8.75 to 11.95–12.21 and the subsequent sulfate contamination decreased the pH to 9.33–11, where the decalcification of calcium silicate hydrate occurred. Further, the effect of sulfate contamination on liquid limit of SRC-treated Soil was negligible, while the plastic and shrinkage limits increased upon sulfate contamination. The increase in the shrinkage limit is attributed to the formation of ettringite/thaumasite in the voids of SRC-treated samples contaminated with 10,000–20,000 ppm sulfate solutions, whereas the monosulfate formation and destruction of cementation gels occurred in samples contaminated with 5000 ppm. These formations are evidenced with the scanning electron microscopy, energy dispersive X-ray analysis, and X-ray diffraction.
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laboratory studies on stabilization of an Expansive Soil by lime precipitation technique
Journal of Materials in Civil Engineering, 2012Co-Authors: T. Thyagaraj, Sai P Suresh, U SaliniAbstract:Lime stabilization prevails to be the most widely adopted in situ stabilization method for controlling the swell-shrink potentials of Expansive Soils despite construction difficulties and its ineffectiveness in certain conditions. In addition to the in situ stabilization methods presently practiced, it is theoretically possible to facilitate in situ precipitation of lime in Soil by successive permeation of calcium chloride (CaCl2 ) and sodium hydroxide (NaOH) solutions into the Expansive Soil. In this laboratory investigation, an attempt is made to study the precipitation of lime in Soil by successive mixing of CaCl2 and NaOH solutions with the Expansive Soil in two different sequences.Experimental results indicated that in situ precipitation of lime in Soil by sequential mixing of CaCl2 and NaOH solutions with Expansive Soil developed strong lime-modification and Soil-lime pozzolanic reactions. The lime-modification reactions together with the poorly de- veloped cementation products controlled the swelling potential, reduced the plasticity index, and increased the unconfined compressive strength of the Expansive clay cured for 24 h. Comparatively, both lime-modification reactions and well-developed crystalline cementation products (formed by lime-Soil pozzolanic reactions) contributed to the marked increase in the unconfined compressive strength of the ex-pansive Soil that was cured for 7–21 days. Results also show that the sequential mixing of Expansive Soil with CaCl2 solution followed by NaOH solution is more effective than mixing Expansive Soil with NaOH solution followed by CaCl2 solution. DOI: 10.1061/(ASCE)MT .1943-5533.0000483. © 2012 American Society of Civil Engineers.
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Lime slurry stabilisation of an Expansive Soil
Geotechnical engineering, 2003Co-Authors: T. ThyagarajAbstract:Lime slurry and lime pile techniques are viable choices for in-situ stabilisation of Expansive Soil deposits. This paper reports the results of a laboratory study on in-situ chemical stabilisation of an Expansive Soil that permeated lime slurry through an artificially desiccated Expansive Soil specimen. The Soil was desiccated in the laboratory to induce shrinkage cracks in the compacted Expansive Soil. The shrinkage cracks greatly assisted migration of lime slurry in the Expansive Soil mass. The efficiency of lime slurry in chemically stabilising the desiccated Expansive Soil was investigated by comparing the physico-chemical properties and engineering properties of the treated Soil with those of the natural Soil specimen at two radial distances. Experimental results indicated that migration of lime slurry through the desiccated Soil promoted strong lime modification and pozzolanic reactions in the Soil mass. The strong Soil–lime reactions rendered the Soil less plastic, reduced the swell magnitude, and ...
J. N. Jha - One of the best experts on this subject based on the ideXlab platform.
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Influence of Rice Husk Ash on the Swelling and Strength Characteristics of Expansive Soil
Geotechnical and Geological Engineering, 2019Co-Authors: Arpit Jain, Anil Kumar Choudhary, J. N. JhaAbstract:Black cotton Soils are Expansive Soils which exhibit high swelling and shrinking when exposed to changes in moisture content. Durability of structure resting on Expansive clays is always in question due to swelling/shrinkage of such clays. The performance of paved and unpaved road pavements constructed over such Expansive Soil subgrades is often poor and in most cases show cracking, potholes, wheel path rutting, serious differential settlements and heaving in various locations. In addition to problems related to Expansive Soils another problem arising in all developing and developed countries is due to the wastes generated from various activities which not only cause severe environmental problems, but also occupy a huge area of land for its disposal. Rice husk ash (RHA) is one such wastes produced from the burning of rice husk and if used as an additive to Expansive Soil shall not only significantly reduce the swelling/shrinkage characteristics of such Soils but also solve the environmental and disposal problems being created by the ash. The paper presents the results of an experimental investigation conducted to study the effect of RHA on swelling, shrinkage and compaction characteristics of the Expansive Soil. The RHA was mixed with Expansive Soil in varying proportions. Free swell index, Atterberg limits, light compaction tests, unconsolidated undrained triaxial compression tests, California bearing ratio tests were carried out with specimens containing varying percentages of RHA. It is concluded that addition of RHA in appropriate proportions not only reduces the swelling and shrinkage behavior of Expansive Soil significantly but also makes it more stable.
