Papers by Prabir Kumar Kolay
Lecture notes in civil engineering, Sep 17, 2020
The paper investigates the use of lime sludge (LS), fly ash (FA) on unconfined compressive streng... more The paper investigates the use of lime sludge (LS), fly ash (FA) on unconfined compressive strength, and shrinkage behavior of commercially available kaolinite clay (EPK). The stabilization process was done using lime sludge alone with varying percentages i.e., 2, 4, 6, and 8% by dry weight, as well as a combination with fly ash in varied percentages i.e., 5, 10, 15, and 20% by dry weight. In order to evaluate the strength properties, standard Proctor tests, and unconfined compressive strength (UCS) tests were performed. For estimating the shrinkage, linear shrinkage test was carried out. The UCS samples were prepared based on the optimum moisture content and dry unit weight from standard Proctor tests. The samples were tested after a curing period of 0, 7, and 14 days. In addition, Scanning Electron Microscopy (SEM) tests were performed on UCS samples after shearing. The test results indicated an increase in UCS value with an increase in lime sludge content. Also, the UCS value increased with curing period following a slight decrease. The combination of LS and FA in varied percentages, also had an increase in UCS strength. Also, the UCS value showed an increment in values with the curing period. The reduction in shrinkage behavior of EPK clay was observed with LS and FA. The SEM analysis was conducted to evaluate the reason for strength increase, which was due to the chemical reaction developed between EPK clay, lime sludge, and fly ash.
The paper presents a slope stability analysis of a proposed embankment contained within an abando... more The paper presents a slope stability analysis of a proposed embankment contained within an abandoned coal mine reclamation project near Sallisaw, Oklahoma. The project involved the use of computer modeling to analyze the slope stability of the earth-filled embankment. The project plans call for mine spoils and silty-clay borrow materials is used to construct a 74,000 cubic yard embankment, which will be used as a water impoundment for a small lake. The embankment, as designed, consists of a central clay core, mine spoils and a silty-clay material cap. The software program Galena was used as a modeling tool for the slope stability analysis of the proposed embankment. Additionally, seven different variations on the embankment's proposed design were modeled. The ultimate goal was to determine the factor of safety (FS) for each variation. Results show that the Galena program provides a higher factor of safety when compared with conventional methods using the Taylor stability chart. The difference in these values is probably attributed to the general assumptions of the Taylor method.
Frontiers in Built Environment, May 29, 2020
Frontiers in Built Environment, Mar 17, 2020
The present study evaluates the liquefaction characteristics of Ottawa sand with polypropylene fi... more The present study evaluates the liquefaction characteristics of Ottawa sand with polypropylene fiber using cyclic triaxial test. A series of stress-controlled cyclic triaxial tests were performed at 34.47 kPa (5 psi) effective confining pressure. Specimens of clean Ottawa sand, and sand containing 0.05, 0.075, 0.1, and 0.3% polypropylene fiber by dry weight of sand were tested at 0.2, 0.25, 0.3, and 0.4 Cyclic Stress Ratio (CSR). Results show a significant improvement in liquefaction resistance when the polypropylene fiber content exceeded beyond 0.075% at 34.47 kPa effective confining stress.
Frontiers research topics, 2020
This eBook is a collection of articles from a Frontiers Research Topic. Frontiers Research Topics... more This eBook is a collection of articles from a Frontiers Research Topic. Frontiers Research Topics are very popular trademarks of the Frontiers Journals Series: they are collections of at least ten articles, all centered on a particular subject. With their unique mix of varied contributions from Original Research to Review Articles, Frontiers Research Topics unify the most influential researchers, the latest key findings and historical advances in a hot research area! Find out more on how to host your own Frontiers Research Topic or contribute to one as an author by contacting the Frontiers Editorial Office: frontiersin.org/about/contac
Geo-Chicago 2016, Aug 8, 2016
Mining Engineering, Dec 1, 2013
Social Science Research Network, 2023
Sustainable civil infrastructures, 2018
The present study investigates the effect of natural aggregate (NA) and recycled concrete aggrega... more The present study investigates the effect of natural aggregate (NA) and recycled concrete aggregate (RCA) in concrete mixture on Freeze-Thaw (F-T) durability. Freeze-thaw action is considered to be one of the most destructive actions that can cause significant damage to concrete pavement structures. To check the F-T durability; various physical, chemical, mechanical properties test has been conducted on the virgin or natural aggregate (NA) and recycled concrete aggregate (RCA) collected from Illinois. The aggregate resistance for degradation has been measured by using micro-deval and sulphate resistance test. The F-T durability of standard concrete mix using various percentages of NA and RCA has been investigated with or without air-entraining admixtures (AEA). The internal damage of the concrete due to rapid freeze-thaw (F-T) has been evaluated by comparing the relative dynamic modulus (RDM) of elasticity of a specimen at the lab, after a specific amount of F-T exposure, to the dynamic modulus test prior to the start of F-T exposure. The results show that concrete sample prepared with air-entrains agent survived more number of F-T cycles and also concrete prepared using RCA samples shows better durability than NA.
"SP-199: Seventh CANMET/ACI International Conference on Fly Ash, Silica Fume, Slag and Natural Pozzolans in Concrete", 2001
The amount of ash, produced from the coal fired thermal power plants and its hazardous impact on ... more The amount of ash, produced from the coal fired thermal power plants and its hazardous impact on the environment is continuously increasing. This poses a challenging task of safe handling, proper disposal and utilization of the ash. The huge quantity of ash produced from these power plants calls for a special attention in terms of its proper utilization, either directly, or conversion into a value-added product. Chemical activation of the coal ash is being practiced for synthesizing ash zeolites. These zeolites are being used for various environmental protection schemes and other industrial processes. With this object in view, an effort has been made in this paper to study the effect of chemical activation of a typical class F lagoon ash. This chemical activation is achieved under controlled conditions, in the laboratory, with different concentrations of alkali (NaOH) and for different durations of activation.
Lecture Notes in Civil Engineering, 2021
World Academy of Science, Engineering and Technology, International Journal of Civil, Environmental, Structural, Construction and Architectural Engineering, 2013
The coal utilization in thermal power plants in Malaysia has increased significantly which produc... more The coal utilization in thermal power plants in Malaysia has increased significantly which produces an enormous amount of coal combustion by-product (CCBP) or coal ash and poses severe disposal problem. As each coal ash is distinct, this study presents the geochemistry of the coal ash, in particular fly ash, produced from the combustion of local coal from Kuching Sarawak, Malaysia. The geochemical composition of the ash showed a high amount of silica, alumina, iron oxides and alkalies which was found to be a convenient starting material for the hydrothermal synthesis of zeolites with the higher Na2O percentage being a positive factor for its alkaline activation; while the mineral phases are mainly quartz, mullite, calcium oxide, silica, and iron oxide hydrate. The geochemical changes upon alkali activation that can be predicted in a similar type of ash have been described in this paper. The result shows that this particular ash has a good potential for a high value industrial produc...
Journal of Civil Engineering, Science and Technology, 2009
Hydraulic conductivity of tropical soils is very complex. Several hydraulic conductivity predicti... more Hydraulic conductivity of tropical soils is very complex. Several hydraulic conductivity prediction methods have focused on laboratory and field tests, such as the Constant Head Test, Falling Head Test, Ring Infiltrometer, Instantaneous profile method and Test Basins. In the present study, Artificial Neural Network (ANN) has been used as a tool for predicting the hydraulic conductivity (k) of some tropical soils. ANN is potentially useful in situations where the underlying physical process relationships are not fully understood and well-suited in modeling dynamic systems on a real-time basis. The hydraulic conductivity of tropical soil can be predicted by using ANN, if the physical properties of the soil e.g., moisture content, specific gravity, void ratio etc. are known. This study demonstrates the comparison between the conventional estimation of k by using Shepard's equation for approximating k and the predicted k from ANN. A programme was written by using MATLAB 6.5.1 and ei...
Journal of Civil Engineering, Science and Technology, 2010
This paper presents the stabilization of local peat soil from Matang, Sarawak, using gypsum and f... more This paper presents the stabilization of local peat soil from Matang, Sarawak, using gypsum and fly ash. Peat soil has been identified as one of the major groups of soils found in Malaysia, which has high compressibility and low shear strength. Presence of soft or peaty soil is a major problem encountered by civil engineers in Sarawak. Different percentages of gypsum (i.e., 2, 4, 6 and 8%) and fly ash (i.e., 5, 10, 15, 20 and 25%) were added into peat soil at optimum moisture content and it’s maximum dry density determined by standard Proctor test. Unconfined compressive strength (UCS) test were conducted to determine the strength gain after 7, 14 and 28 days of curing periods. Physical properties of the peat soil have also been studied for identification and classification purposes. The unconfined compressive strength test results show that the peat soil gained strength due to the addition of different percentages of admixtures such as gypsum and fly ash and the strength also incre...
International Journal of Geosynthetics and Ground Engineering, 2019
This paper presents the results of effects of non-plastic fines (Class F fly ash) on liquefaction... more This paper presents the results of effects of non-plastic fines (Class F fly ash) on liquefaction behavior of Ottawa sand. Stresscontrolled cyclic triaxial tests were performed on clean Ottawa sand, fly ash, and sand-fly ash mixtures containing 10, 20, 25, 30, 50, and 70% of fly ash. For the evaluation of the effects of confining pressure on liquefaction resistance, three series of tests were conducted at 34.48, 68.96, and 103.42 kPa initial effective confining pressures, except for pure fly ash. In the case of pure fly ash, tests were conducted only at an effective confining pressure of 34.48 kPa. The reversible shear stress was applied systematically by varying Cyclic Stress Ratio from 0.1 to 0.5. Addition of fly ash to sand resulted in decrease in liquefaction resistance initially and then increase in liquefaction resistance for fly ash contents up to about 20-25%. Increase in fly ash content beyond 25% was seen to decrease the liquefaction resistance.
International Journal of Environmental Engineering, 2016
The major by-product of coal-fired thermal power plants is pulverised fuel ash (PFA) and the comm... more The major by-product of coal-fired thermal power plants is pulverised fuel ash (PFA) and the common method of disposal of PFA is wet disposal method. In this method, PFA and bottom ashes are mixed with water, which made them slurry, and are disposed in ash pond or lagoons. If the lagoons are not properly designed with liner or if there is spillage from the lagoons, the toxic heavy metals present in the PFA can contaminate soil or ground water. Hence, this study concentrates on the leaching of PFA sample collected from Malaysia. The leachability of PFA was investigated by column model with different liquid-to-solid (L/S) ratio and pH values. It was found that the concentration of trace elements increases with the increase in acidity and decreases with higher L/S ratio. Also, some trace elements exceeded the standards set by The Ministry of Health Malaysia, hence are hazardous to the environment.
Computer Methods and Recent Advances in Geomechanics, 2014
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Papers by Prabir Kumar Kolay