Thickness Of Compact Layer Research Articles

Influence of gas boriding on corrosion resistance of Inconel 600-alloy

Purpose: The aim of this study was to analyse the corrosion behaviour of gas-borided layers produced on Inconel 600-alloy. Two types of the borided layers were produced: fully borided and partially borided layer. The results obtained for gas-borided specimens were compared to untreated Inconel 600-alloy. Design/methodology/approach: In this paper, gas boriding in N2-H2-BCl3 atmosphere was applied to produce the boride layers on Inconel 600-alloy. This process was carried out at 910°C (1193 K) for 2 h. Microstructure observations were carried out using a light microscope. The hardness measurements were performed using a Vickers method under a load of 0.981 N. In order to evaluate the corrosion resistance, the immersion corrosion test in a boiling solution of H2O, H2SO4 and Fe2(SO4)3 was used. Findings: The gas-borided layers consisted of a mixture of nickel borides (Ni3B, Ni2B, Ni4B3, NiB) and chromium borides (CrB, Cr2B). The high thickness of compact boride layer (76-79 μm) as well as high hardness (up to 2061 HV) were obtained. Based on corrosion resistance tests it was found that in case of untreated sample the strong intergrannular attack was observed. Whereas the corrosion behavior ofgas-borided Inconel 600-alloy was more complicated and resulted from the surface condition. Research limitations/implications: The obtained results indicated that gas-boriding in N2-H2-BCl3 atmosphere could be a suitable corrosion protection if the whole surface would be covered with boride layer. Practical implications: The parameters of gas boriding in N2-H2-BCl3 atmosphere used in this study (temperature of 910°C for 2 h) allowed to produced layers of a higher thickness in comparison with other acceptable method of boriding e.g. powder-pack boriding. Originality/value: Based on the results it was found that gas-boriding in N2-H2-BCl3 atmosphere is a suitable method to protect Inconel 600-alloy from corrosion.

Correlation of Non-Compact Myocardial Layer Characteristics With the Risk of Death and Thrombotic Complications in Dilated Phenotype of Non-Compact Myocardium in Children: Cohort Study Results

Background: Non-compact myocardium is a form of cardiomyopathy, which is characterized by an abnormal trabecular (non-compact) layer of the ventricular myocardium. The correlation between the severity of a non-compact myocardial layer and peculiarities of course and outcome of the disease remains unclear. Objective: Our aim was to examine the relationship of the ratio value of the non-compact and compact myocardial layer (NC/C) thickness, as well as of the number of non-compact segments of the left ventricle (LV) of the heart with the risk of death and thrombotic complications in children with dilated phenotype of non-compact myocardium. Methods: The results of a prospective cohort study, which included children hospitalized to a specialized hospital from October 2011 to May 2015, are presented. The presence of non-compact myocardium was established on the basis of echocardiography results. Results : The study included 48 children with non-compact myocardium and LV myocardium remodelling on the dilatation phenotype. Fatal outcome in 19 (8; 61) months from the date of detection of heart changes occurred in 11 (23%) cases. The development of thrombotic complications (cardioembolism, intravascular thrombosis before or during the observation) is recorded in 8 (17%) children. The risk of death and thrombotic complications did not depend on the NC/C value and the number of non-compact LV segments. Conclusion: The value of the ratio of NC/C and the number of non-compact LV myocardial segments does not allow to predict the course of the disease in children with dilated phenotype of non-compact myocardium in relation to the development of thrombotic complications and occurrence of fatal outcome.

Compact layer influence on hysteresis effect in organic–inorganic hybrid perovskite solar cells

Organic–inorganic hybrid perovskite solar cells have attracted great attention due to their high power conversion efficiency and low cost. However, an anomalous hysteresis effect exists in the perovskite solar cells, especially with TiO2 as the n-type electron extraction layer. In this communication, we prepare two kinds of TiO2 compact layers using Atomic Layer Deposition (ALD) and Spin-Coating (SC) methods and compare their influences on the hysteresis effect. By efficiency comparison and AC impedance spectroscopy study, we find that the thickness and morphology of compact layer have a significant influence on the hysteresis effect. Compared to the SC approach, the ALD prepared compact layer is ultra-thin with uniform morphology and shows small interfacial capacitance and large recombination resistance, meaning reduced interfacial charge accumulation and accelerated electron transport, which would relieve the hysteresis effect.

Preparation of ultra-thin and high-quality WO3 compact layers and comparision of WO3 and TiO2 compact layer thickness in planar perovskite solar cells

In this paper, the ultra-thin and high-quality WO3 compact layers were successfully prepared by spin-coating-pyrolysis method using the tungsten isopropoxide solution in isopropanol. The influence of WO3 and TiO2 compact layer thickness on the photovoltaic performance of planar perovskite solar cells was systematically compared, and the interface charge transfer and recombination in planar perovskite solar cells with TiO2 compact layer was analyzed by electrochemical impedance spectroscopy. The results revealed that the optimum thickness of WO3 and TiO2 compact layer was 15nm and 60nm. The planar perovskite solar cell with 15nm WO3 compact layer gave a 9.69% average and 10.14% maximum photoelectric conversion efficiency, whereas the planar perovskite solar cell with 60nm TiO2 compact layer achieved a 11.79% average and 12.64% maximum photoelectric conversion efficiency.

Steady state performance, photo-induced performance degradation and their relation to transient hysteresis in perovskite solar cells

Hysteresis in current-voltage curves of perovskite solar cells is a serious concern as it creates confusions about actual cell performance and raises questions on its reliability. Although a lot of effort has been made to understand the origin of hysteresis, knowing whether hysteresis affects the cell performance while they are in practical use (operated constantly at maximum power point) is not yet examined. In the present study, we investigate steady state performance and performance stability of perovskite solar cells (planar architecture with varying perovskite film thickness and TiO2 mesoscopic structure with different TiO2 compact layer thickness exhibiting hysteresis of different magnitudes) operating across an external load in relation to hysteresis. The planar cells with larger hysteresis exhibit a steady state current that closely matches the value determined on forward voltage scan. Cyclic photocurrent–dark current measurements on cells with hysteresis of different magnitudes reveal that photo-induced electrical instability (not material degradation), which might be originated from ion migration or photo-induced traps formation, is not related to hysteresis. Performance of the cells is recovered partially or fully, depending on the device structure, on storage in dark. TiO2 meso-structure cells tend to show complete recovery while the planar cells recover partially.

The effect of AZO and compact TiO2 films on the performance of dye-sensitized solar cells

This paper presents a scheme that produces the optimal deposition parameters for inexpensive Al-doped zinc oxide (AZO, transparent conducting oxide) films and compact TiO2 layers. This scheme improves the performance of dye-sensitized solar cells (DSSC) that are produced by radio frequency (rf) magnetron sputtering onto soda-lime glass substrates. The results show that using the grey relational Taguchi method, the electrical resistivity of AZO films is reduced from 6.2 to 3.4×10−3Ω-cm and the visible range optical transmittance is changed, from 88.7 to 88.8%. The (002) diffraction peaks for the AZO films are sharper and their full width at half maximum is narrower, which demonstrates that the crystalline structure of the AZO films is improved. Post-annealing increases the grain size of the AZO films, which leads to further decreased resistivity from 3.4 to 1.72×10−3Ω-cm because there is an increase in the carrier concentration and the Hall mobility. A compact TiO2 layer is achieved using rf sputtering deposition and the effect of the thickness (40, 70, 100 150 and 200nm) on the DSSC conversion efficiency is determined. The effect of TiO2 compact layer prevents electron transport to the electrolyte and a higher short-circuit current density will be obtained. The experimental results show that the DSSC conversion efficiency is critically affected by the thickness of the compact TiO2 layer, and the thickness of compact layer is about 100nm will leads to the optimal efficiency.

Dependence of device performance on the thickness of compact TiO2 layer in perovskite/TiO2 planar heterojunction solar cells

Planar heterojunction perovskite solar cells (PHJ-PSCs) based on CH3NH3PbI3/TiO2 with high-quality CH3NH3PbI3 films were fabricated by two-step interdiffusion technology. The photovoltaic performance of PHJ-PSCs, including short-circuit-current (Jsc) and open-circuit-voltage (Voc), was found to be strongly dependent on the thickness of TiO2 layer. The largest Jsc was obtained at an optimized TiO2 thickness of 65 nm, resulting in a moderate power conversion efficiency (PCE) of 8.40% with a device structure of fluorine doped SnO2/compact TiO2/CH3NH3PbI3/Spiro-MeOTAD/Ag. A thicker compact TiO2 film could lead to a lower Voc, and the physical mechanism between the Voc and the thickness of compact TiO2 layer was disclosed.

Warm acclimation and oxygen depletion induce species-specific responses in salmonids.

Anthropogenic activities are greatly altering the habitats of animals, whereby fish are already encountering several stressors simultaneously. The purpose of the current study was to investigate the capacity of fish to respond to two different environmental stressors (high temperature and overnight hypoxia) separately and together. We found that acclimation to increased temperature (from 7.7±0.02°C to 14.9±0.05°C) and overnight hypoxia (daily changes from normoxia to 63-67% oxygen saturation), simulating climate change and eutrophication, had both antagonistic and synergistic effects on the capacity of fish to tolerate these stressors. The thermal tolerance of Arctic char (Salvelinus alpinus) and landlocked salmon (Salmo salar m. sebago) increased with warm acclimation by 1.3 and 2.2°C, respectively, but decreased when warm temperature was combined with overnight hypoxia (by 0.2 and 0.4°C, respectively). In contrast, the combination of the stressors more than doubled hypoxia tolerance in salmon and also increased hypoxia tolerance in char by 22%. Salmon had 1.2°C higher thermal tolerance than char, but char tolerated much lower oxygen levels than salmon at a given temperature. The changes in hypoxia tolerance were connected to the responses of the oxygen supply and delivery system. The relative ventricle mass was higher in cold- than in warm-acclimated salmon but the thickness of the compact layer of the ventricle increased with the combination of warm and hypoxia acclimation in both species. Char had also significantly larger hearts and thicker compact layers than salmon. The results illustrate that while fish can have protective responses when encountering a single environmental stressor, the combination of stressors can have unexpected species-specific effects that will influence their survival capacity.

Freezing colloidal suspensions: periodic ice lenses and compaction

AbstractRecent directional solidification experiments with aqueous suspensions of alumina particles (Anderson & Worster, Langmuir, vol. 28 (48), 2012, pp. 16512–16523) motivate a model for freezing colloidal suspensions that builds upon a theoretical framework developed by Rempel et al. (J. Fluid Mech., vol. 498, 2004, pp. 227–244) in the context of freezing soils. Ice segregates from the suspension at slow freezing rates into discrete horizontal layers of particle-free ice, known as ice lenses. A portion of the particles is trapped between ice lenses, while the remainder are pushed ahead, forming a layer of fully compacted particles separated from the bulk suspension by a sharp compaction front. By dynamically modelling the compaction front, the growth kinetics of the ice lenses are fully coupled to the viscous flow through the evolving compacted layer. We examine the periodic states that develop at fixed freezing rates in a constant, uniform temperature gradient, and compare the results against experimental observations. Congruent with the experiments, three periodic regimes are identified. At low freezing rates, a regular periodic sequence of ice lenses is obtained; predictions for the compacted layer thickness and ice-lens characteristics as a function of freezing rate are consistent with experiments. At intermediate freezing rates, multiple modes of periodic ice lenses occur with a significantly diminished compacted layer. When the cohesion between the compacted particles is sufficiently strong, a sequence of mode-doubling bifurcations lead to chaos, which may explain the disordered ice lenses observed experimentally. Finally, beyond a critical freezing rate, the regime for sustained ice-lens growth breaks down. This breakdown is consistent with the emergence of a distinct regime of ice segregation found experimentally, which exhibits a periodic, banded structure that is qualitatively distinct from ice lenses.

Influence of compact TiO2 layer on the photovoltaic characteristics of the organometal halide perovskite-based solar cells

A series of perovskite-based solar cells were fabricated wherein a compact layer (CL) of TiO2 of varying thickness (0–390nm) was introduced by spray pyrolysis deposition between fluorine-doped tin oxide (FTO) electrode and TiO2 nanoparticle layer in perovskite-based solar cells. Investigations of the CL thickness-dependent current density–voltage (J–V) characteristics, dark current, and open circuit voltage (Voc) decays showed a similar trend for thickness dependence. A CL thickness of 90nm afforded the perovskite-based solar cell with the maximum power conversion efficiency (η, 3.17%). Furthermore, two additional devices, perovskite-based solar cell omitting hole transporting materials layer and cell without the TiO2 nanoparticles, were designed and fabricated to study the influence of the CL thickness on different electron transport paths in perovskite-based solar cells. Solar cells devoid of TiO2 nanoparticles, but with perovskite and organic hole-transport materials (HTMs), exhibited sustained improvement in photovoltaic performances with increase in the thickness of CL, which is in contrast to the behavior of classical perovskite-based solar cell and common solid state solar cell which showed optimal photovoltaic performances when the thickness of CL is 90nm. These observations suggested that TiO2 nanoparticles play a significant role in electron transport in perovskite-based solar cells.

Sputtered TiOx thin film as compact layer for solid-state dye sensitized solar cells

This study investigates the TiO x compact layers deposited by mid-frequency magnetron sputtering of Ti target under a gaseous atmosphere of Ar/O 2 . X-ray photoelectron spectroscopy suggests that the compact layer consists of 55% Ti 3+ and 45% Ti 4+ . Current–voltage measurements reveal that the TiO x film effectively impedes the leakage of current at the FTO/hole transporting material (HTM) interface. Current–voltage curves, electrochemical impedance spectroscopy and open-circuit voltage decay are used to evaluate the function of TiO x compact layer in the solid-state solar cells. Results show that the best cell performance is observed in the cell with optimum compact layer thickness of 85 nm, which shows 814% increase in the power conversion efficiency (PCE) when compared with the bare cell. Thicker TiO x film suppresses the charge recombination more effectively, leading to longer electron lifetime of the solar cells. Nevertheless, higher resistance of the thicker TiO x film decreases its electron transport ability, thereby leading to lower PCE. Besides, compared to liquid-state solar cells, solid-state solar cells require thicker TiO x compact layer to block the electron loss and show larger increase of PCE (highest 27% enhancement in liquid-state solar cells with 85 nm TiO x layer), which corresponds to the much faster charge recombination and ~15 times lower electron-carrier lifetime in solid-state solar cell.

Modeling within field variation of the compaction layer in a paddy rice field using a proximal soil sensing system

AbstractA key characteristic of flooded paddy fields is the plough pan. This is a sub‐soil layer of greater compaction and bulk density, which restricts water losses through percolation. However, the thickness of this compacted layer can be inconsistent, with consequences such as variable percolation and leaching losses of nutrients, which therefore requires precision management of soil water. Our objective was to evaluate a methodology to model the thickness of the compacted soil layer using a non‐invasive electromagnetic induction sensor (EM38‐MK2). A 2.7 ha alluvial non‐saline paddy rice field was measured with a proximal soil sensing system using the EM38‐MK2 and the apparent electrical conductivity (ECa) of the wet paddy soil was recorded at a high‐resolution (1.0 × 0.5 m). Soil bulk density (n = 10) was measured using undisturbed soil cores, which covered locations with large and small ECa values. At the same locations (within 1 m2) the depth of the different soil layers was determined by penetrometer. Then a fitting procedure was used to model the ECa – depth response functions of the EM38‐MK2, which involved solving a system of non‐linear equations and a R2 value of 0.89 was found. These predictions were evaluated using independent observations (n = 18) where a Pearson correlation coefficient of 0.87 with an RMSEE value of 0.03 m was found. The ECa measurements allowed the detail estimation of the compacted layer thickness. The link between water percolation losses and thickness of the compacted layer was confirmed by independent observations with an inverse relationship having a Pearson correlation coefficient of 0.89. This rapid, non‐invasive and cost‐effective technique offers new opportunities to measure differences in the thickness of compacted layers in water‐saturated soils. This has potential for site‐specific soil management in paddy rice fields.

Roller Compacted Concrete Dam Compacted Thickness Increased Analytical Quality Assurance

At present, roller compacted concrete (called RCC) technology has developed rapidly. So in order to make the RCC dam, RCC dam construction technologies have been further developed and accelerate its construction schedule. Many projects have begun to regulate the conduct of RCC which has been breakthrough in compaction layer thickness 30cm field test, which by increasing RCC compaction layer thickness. Many experiments construction proved that: RCC roller compacted concrete layer thickness increasing is feasible. However the increasing compaction thickness, the deck construction process and the successful completion of the jelling time of concrete is the key factors to ensure quality of the dam. It is the big prerequisite for completion. We will integrate field test to the quality control of the dam after the compacted layer thickness is increased.

Relationship between left ventricular sphericity and trabeculation indexes in patients with dilated cardiomyopathy: a cardiac magnetic resonance study

To study the relationship between left ventricular (LV) trabeculations, volume, and sphericity in patients with dilated cardiomyopathy (DCM) by cardiac magnetic resonance imaging (CMR). Eighty-two patients with DCM were prospectively explored by CMR. The segmental trabeculation index (STI) was defined by the ratio of trabeculated layer thickness on compacted layer thickness per segment. The global trabeculation index (GTI) was defined by the ratio of the sum of the total trabeculated layer thickness to the sum of the total compacted layer thickness. The apex was excluded from the analysis. The mean number of segments with trabeculation per patient was 10 ± 2 with a mean GTI of 0.68 ± 0.32. The LV sphericity index was inversely correlated with LV ejection fraction (R = -0.42, P = 0.0002) and positively with the brain natriuretic peptide (BNP) level (R = 0.34, P = 0.003). The maximal STI was positively correlated with the indexed LV end-diastolic volume (R = 0.32, P = 0.004) and the LV sphericity index (R = 0.25, P = 0.02), but not with the BNP level or LV ejection fraction. The GTI was positively correlated with the LV sphericity index (R = 0.27, P = 0.016) but not with indexed LV end-diastolic volume, BNP levels, or LV ejection fraction. Trabeculation indexes depend on LV shape and are positively correlated with LV sphericity. These results encourage interpreting LV trabeculation with caution in patients with DCM, considering additional morphologic criteria such as LV geometry.

The effects of the electrical double layer on giant ionic currents through single-walled carbon nanotubes

We developed a computational model for investigating the cause for the high ionic current through a single-walled carbon nanotube nanofluidic device by considering the electrical double layer at a solid–liquid interface. With this model, we were able to examine the influence of the Gouy–Chapman–Stern electrical double layer and the solution concentration on the ionic conductance in the device. Results showed that the conductance–concentration relationship predicted from our model agreed well with experimental observation. Moreover, our model showed that the compact layer thickness increased with the increase of the bulk solution concentration, reducing the internal volume of the nanotube channel available for fluid transport. Fluid within the channel had an enhanced concentration and a net charge which increased the electroosmotic and electrophoretic transport properties of the device, increasing the total ionic conductance of the system.

Chalk fill platform for house construction: a case study

This paper presents the assessment of short- and long-term settlements and bearing capacity of a 13 m high chalk fill platform for a housing development in a former chalk quarry in Medway Gate, Kent, UK. A roped-access inspection followed by an intrusive site investigation provided evidence that the quality of in situ chalk improved with depth. It was also indicated that there was sufficient structured chalk on site for the platform construction. End-product specification with the stipulation of dry density and moisture content limits was used for the required chalk compaction. Trial compactions were carried out to confirm roller suitability and the thickness of each compacted layer. Nuclear density tests supplemented by sand replacement and laboratory tests provided a quick means of monitoring dry density and moisture content during construction. In situ plate bearing tests confirmed that compacted chalk with a dry density above 1·55 Mg/m3 could generally provide a bearing capacity greater than 150 kN/m2 as required in the contract. Post-construction settlement monitoring results indicated both immediate and creep settlements in the compacted chalk, and confirmed the time required for creep settlement to complete: hence the suitable timing for house construction.

The optimization of TiO2 compact layer in dye‐sensitized solar cell by the analysis of performance and internal impedance

AbstractThe working electrode of a Dye–sensitized Solar Cell (DSC) is a fluorine‐doped tin oxide (FTO) glass substrate pasted with nano‐porous TiO2. Under the illumination, dye molecules are excited and electrons are emitted. The electrons pass through two interfaces of dye/TiO2 and TiO2/FTO. Therefore, electron of the TiO2 conduction band combines with I3‐ ion of the electrolyte. A compact layer between the FTO and nano‐porous TiO2 layer makes adherence of TiO2 to FTO surface improved, and the electron recombination reduced because it blocks the direct contact between the redox electrolyte and the FTO surface. Although some researches have studied the insertion of compact layer so far, only materials and the coating methods were studied. To the best of our knowledge, there was no study of a correlation between thickness and efficiency. Therefore, in this study, we investigated on the change in the output characteristics of DSCs according to thickness of TiO2 compact layer fabricated by coating in TiCl4 aqueous solution. The thickness of compact layer was controlled by repetitive coatings and measured by field emission scanning electron microscopy. The effects in terms of the I‐V characteristics and the electrochemical impedance spectroscopy (EIS) were examined for the analysis of the change in the thickness of TiO2 compact layer. As a result, the optimum thickness which has the highest output in the I‐V characteristics and the smallest area of EIS semi‐circle was derived. And the photovoltaic performance of DSC with an optimum compact layer was maximized (© 2011 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)

Long-term experiments aimed at improving tillage practices

The Crop Production Institute of Szent István University carried out soil quality trials in the region of Gödöllő between 1977 and 2002, followed by similar experiments near the town of Hatvan since 2002. Soil quality factors that can be improved by tillage include the looseness of the root zone, the depth of the loosened layer, the duration of the loosened state, the thickness of the compact layer impeding water transport, the soil structure, the level of surface protection, the water intake/water loss balance, the organic material balance and earthworm activity. Optimising these factors can help reduce climate stress, so that extreme weather conditions do not undermine the reliability of farming. Most of the tillage methods elaborated on the basis of the findings of the trials, with the aim of alleviating climate stress, differ from conventional recommendations.

Imposed currents in galvanic cells

We analyze the steady-state behavior of a general mathematical model for reversible galvanic cells, such as redox flow cells, reversible solid oxide fuel cells, and rechargeable batteries. We consider not only operation in the galvanic discharging mode, spontaneously generating a positive current against an external load, but also operation in two modes which require a net input of electrical energy: (i) the electrolytic charging mode, where a negative current is imposed to generate a voltage exceeding the open-circuit voltage, and (ii) the “super-galvanic” discharging mode, where a positive current exceeding the short-circuit current is imposed to generate a negative voltage. Analysis of the various (dis-)charging modes of galvanic cells is important to predict the efficiency of electrical to chemical energy conversion and to provide sensitive tests for experimental validation of fuel cell models. In the model, we consider effects of diffuse charge on electrochemical charge-transfer rates by combining a generalized Frumkin-Butler-Volmer equation for reaction kinetics across the compact Stern layer with the full Poisson-Nernst-Planck transport theory, without assuming local electroneutrality. Since this approach is rare in the literature, we provide a brief historical review. To illustrate the general theory, we present results for a monovalent binary electrolyte, consisting of cations, which react at the electrodes, and non-reactive anions, which are either fixed in space (as in a solid electrolyte) or are mobile (as in a liquid electrolyte). The full model is solved numerically and compared to analytical results in the limit of thin diffuse layers, relative to the membrane thickness. The spatial profiles of the ion concentrations and electrostatic potential reveal a complex dependence on the kinetic parameters and the imposed current, in which the diffuse charge at each electrode and the total membrane charge can have either sign, contrary perhaps to intuition. For thin diffuse layers, simple analytical expressions are presented for galvanic cells valid in all three (dis-)charging modes in the two subsequent limits of the ratio δ of the effective thicknesses of the compact and diffuse layers: (i) the “Helmholtz limit” ( δ → ∞) where the compact layer carries the double layer voltage as in standard Butler-Volmer models, and (ii) the opposite “Gouy-Chapman limit” ( δ → 0) where the diffuse layer fully determines the charge-transfer kinetics. In these limits, the model predicts both reaction-limited and diffusion-limited currents, which can be surpassed for finite positive values of the compact layer, diffuse layer and membrane thickness.

Bearing ratio of reinforced fly ash overlying soft soil and deformation modulus of fly ash

This paper presents the laboratory study on the bearing ratio of unreinforced and reinforced fly ash overlying soft soil beds of a total of 11 fly ash samples collected from different thermal power plants located in the Eastern part of India. The thickness of the bottom clay layer ( H c) was maintained as 100 mm in the bearing ratio mould. The upper layer thickness of compacted fly ash ( H f) was varied. The values of the ratio H f / H c used were 0.75, 1.00 and 1.25 in this study. The fly ash layer was reinforced with single layer and double layers of geotextiles. The effects of (i) position and number of layers of geotextiles, (ii) thickness of the compacted fly ash layer overlying soft soil layer, and (iii) moulding water content of the soft soil, on the bearing ratio of fly ash are highlighted. The inclusion of geotextile into the compacted fly ash bed enhances the bearing ratio. An increase in the thickness of compacted fly ash layer over the soft soil layer also increases the bearing ratio of the compacted fly ash bed. The values of unconfined compressive strength and deformation modulus of all the fly ash samples are also presented. Empirical relationships to estimate deformation modulus of fly ash from unconfined compressive strength and relationships between initial tangent modulus and secant modulus of fly ash are presented. It may be concluded from this research study that reinforced compacted fly ash overlying soft soil with a geotextile layer at the interface can find potential application in the construction of roads over soft soil.