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Fly ash (FA), a by-product of the power generation industry, can potentially be used as a filler in polymer products. Particularly, FA has been investigated as an alternative filler to partially or fully replace commercial fillers in polymer composites. This mini-review discusses the fundamental properties of FA, environmental pollution from commercial fillers, and the performance of FA in polymers. The properties of FA-loaded polymer composites are discussed, including the morphological, rheological, mechanical, and thermal properties. This review highlights the potential methods and challenges for substituting, or replacing, commercial fillers in various polymers such as natural rubber (NR), epoxidized NR, epoxy, styrene-butadiene rubber (SBR), NR/SBR blends, polyethylene, polypropylene, and polyester. KEYWORDS alternative filler, by-product, fly ash, mechanical properties, polymers, 1 | INTRODUCTION Pollution is a growing concern worldwide. Society and the environment are confronted with a complex combination of numerous air pollutants that are emitted from diverse sources. Especially, [...]

Geopolymer concrete's workability and compressive strength were investigated by changing the ratio of alkali activators to each other ([Na.sub.2]Si[O.sub.3]/NaOH), the ratio of total solutions to fly ash, and the water content of aggregate. According to the findings, the saturated surface dry condition of the aggregate, in terms of water content in general, increases the workability and compressive strength. In addition, because of the reduction in the [Na.sub.2]Si[O.sub.3]/NaOH ratio, the concrete sets and solidifies faster, and the compressive strength and modulus of elasticity increase. Increasing the ratio of total solutions to fly ash prolongs the setting time but decreases the strength and elasticity modulus and increases the strain corresponding to the maximum stress. As a result, the strain corresponding to the maximum compressive strength of geopolymer concrete is higher, and the modulus of elasticity is lower than that of ordinary Portland cement concrete. Key words: geopolymer concrete, fly ash, mechanical properties, green concrete, alkaline activator, 1. Introduction Portland cement concrete (ordinary Portland cement, OPC) is still a leading construction material due to its high strength, long service life, easy application, and low cost. Concrete production, [...]

To address the negative contribution of cement production on global carbon emissions, this study aims to reduce the cement content typically required in concrete by using partial replacement by gypsum powder recycled from waste drywalls (15%) and fly ash (50%), by weight. The durability of concrete cylinders made of the mixture was evaluated by testing the cylinders in compression after exposure to various environmental conditions for 1000, 3000, and 5000 h. A total of 45 specimens under 5 exposure conditions were considered. The conditions included dry, submerged in fresh water, submerged in seawater, and two groups rotated weekly between dry and submerged in either fresh water or seawater. Overall, specimens in both freshwater and seawater conditions after 5000 h showed strength higher than control specimens. Results indicate that the strength of the concrete specimens containing recycled gypsum powder and fly ash was not adversely affected by exposure to the conditions. Key words: concrete, durability, recycled gypsum, waste drywall, fly ash, compression Pour remedier a la contribution negative de la production de ciment aux emissions mondiales de carbone, cette etude vise a reduire la teneur en ciment habituellement requise dans le beton en la remplacant partiellement par de la poudre de gypse recyclee a partir de dechets de cloisons seches (15%) et de cendres volantes (50%), en poids. La durabilite des cylindres en beton du melange a ete evaluee en mettant a l'essai les cylindres en compression apres exposition a diverses conditions environnementales pendant 1000, 3000 et 5000 h. Au total, 45 specimens dans cinq conditions d'exposition ont ete pris en consideration. Les conditions etaient les suivantes : sec, submerge dans de l'eau douce, submerge dans de l'eau de mer, et deux groupes tournant chaque semaine entre sec et submerge dans de l'eau douce ou de l'eau de mer. Dans l'ensemble, les echantillons en eau douce et en eau de mer apres 5000 h ont montre une resistance superieure a celle des echantillons temoins. Les resultats indiquent que la resistance des echantillons de beton contenant de la poudre de gypse recyclee et des cendres volantes n'a pas ete touchee par l'exposition aux conditions. [Traduit par la Redaction] Mots-cles : beton, durabilite, gypse recycle, dechets de cloisons seches, cendres volantes, compression, Introduction The production of Portland cement causes negative environmental impacts by releasing large amounts of carbon dioxide (C[O.sb.2]) into the atmosphere, and appropriately many efforts are being made to reduce [...]

The generation of coal fly ash (CFA) in coal-fired power plants worldwide has been a major concern over the past few decades. CFA as a by-product possesses unique properties and chemical composition that could be utilized in resolving mercury contamination issues in Central Asia, particularly in Kazakhstan. This review gives an overview of coal generation capacity and evaluation of the current state of electricity production and ecological concerns related to CFA accumulation. We provide a detailed comparison of the physical properties and chemical compositions of three types of CFAs from Kazakhstani power plants, and present potential approaches to help alleviate mercury contamination issues. Furthermore, this review highlights the current state of mercury contamination in artificial Lake Balkyldak and in the Nura River of the north and central regions of Kazakhstan. Of particular interest is the appropriate utilization of CFAs in resolving mercury contamination issues by highlighting and comparing the state-of-the-art technology of porous and nonporous materials currently reported in the literature. Key words: coal production, coal fly ash, mercury contamination, utilization, Kazakhstan La production de cendres volantes de charbon (CFA, coal fly ash) dans les centrales électriques au charbon du monde entier a été une préoccupation majeure au cours des dernières décennies. Les CFA, en tant que sous-produit, possèdent des propriétés et une composition chimique uniques qui pourraient être utilisées pour résoudre les problèmes de contamination au mercure en Asie centrale, en particulier au Kazakhstan. Cet article de synthèse donne un aperçu de la capacité de production de charbon et une évaluation de l'état actuel de la production d'électricité et des préoccupations écologiques liées àl'accumulation de CFA. Les auteurs présentent une comparaison détaillée des propriétés physiques et des compositions chimiques de trois types de CFA provenant de centrales électriques kazakhes, et présentent des approches potentielles pour aider àatténuer les problèmes de contamination au mercure. En outre, cette étude met en évidence l'état actuel de la contamination par le mercure dans le lac artificiel Balkyldak et dans la rivière Nura des régions du nord et du centre du Kazakhstan. Un élément d'intérêt particulier consiste en l'utilisation appropriée des CFA dans la résolution des problèmes de contamination au mercure en mettant en évidence et en comparant les technologies de pointe des matériaux poreux et non poreux et actuellement rapportées dans la littérature. [Traduit par la Rédaction] Mots-clés : production de charbon, cendres volantes de charbon, contamination au mercure, utilisation, Kazakhstan, Introduction Coal fly ash (CFA) is a solid waste material typically discharged and generated from coal-fired thermal power plants (CFTPPs). The Eurasian region is one of the major consumers of [...]

The corrosion resistance of fly ash-based geopolymer structural concrete (GPC), with or without fibers, was investigated in a simulated marine environment, and compared with that of ordinary Portland cement structural concrete. The corrosion behavior is studied through an electrochemical method for inducing accelerated corrosion. The fiber reinforced beam specimens contained polyolefin fibers in the amounts of 0.1%, 0.3%, and 0.5% by volume. Several artificial corrosion conduits were introduced into the specimens reaching up to the rebars. This process enhanced the rate of laboratory corrosion in GPC, thus allowing faster and measurable evaluation of corrosion resistance. The corrosion-damaged beams were then analyzed through a method of crack scoring, and determination of steel mass loss and residual flexural load capacity. The fiber reinforced corroded GPC beams (with 0.1-0.5% fibers) showed a 24% reduction in crack scores, and a 109% increase in residual flexural load capacity, compared to unreinforced corroded GPC beams. This shows promise of fiber-reinforced GPC as a sustainable structural material in the marine environment. Key words: geopolymer concrete, fly ash, sustainable, polyolefin fiber, corrosion resistance. La resistance a la corrosion du beton de structure en geopolymere (BSG) a base de cendres volantes, avec ou sans fibres, a ete etudiee dans un environnement marin simule, et comparee a celle du beton de structure en ciment ordinaire Portland. Le comportement a la corrosion est etudie par une methode electrochimique pour induire une corrosion acceleree. Les echantillons de poutres renforcees de fibres contenaient des fibres de polyolefines en quantites de 0,1, 0,3 et 0,5 % en volume. Plusieurs conduites de corrosion artificielle ont ete introduites dans les echantillons atteignant les barres d'armature. Ce processus a ameliore le taux de corrosion du BSG en laboratoire, permettant ainsi une evaluation plus rapide et mesurable de la resistance a la corrosion. Les poutres endommagees par la corrosion ont ensuite ete analysees au moyen d'une methode de notation des fissures et de determination de la perte de masse d'acier et de la capacite de flexion residuelle. Les poutres de BSG renforcees de fibres (avec des fibres de 0,1 a 0,5 %) ont montre une reduction de 24 % des fissures et une augmentation de 109 % de la capacite de flexion residuelle par rapport aux poutres de BSG corrodees non renforcees. Cela montre la promesse de BSG en fibres renforcees comme un materiau structurel durable dans l'environnement marin. [Traduit par la Redaction] Mots-cles: beton geopolymere, cendres volantes, durable, fibre de polyolefine, resistance a la corrosion., Introduction and background Geopolymer paste was conceived by Davidovits (1991) as an inorganic polymer. Geopolymerization is an exothermic reaction, and involves the chemical reaction of alumino-silicate oxides ([Si.sub.2][O.sub.5], [Al.sub.2][O.sub.2]) with [...]

This research focused on the role of fly ash and silica fume on slag geopolymer concrete through investigating workability (slump, and slump loss), initial setting time, final setting time, and mechanical properties of slag geopolymer concrete (S-GPC) (compressive strength, splitting tensile strength, modulus of elasticity) in addition to scanning electron microscope (SEM) and X-ray analysis. The considered variables included fly ash content as a replacement of ground granulated blast furnace slag (GS) (0%, 10%, 20%, 30%, and 40%), presence of silica fume as a replacement for slag, concentration of sodium hydroxide, NaOH, (molarity: 10,16, and 18 mol/L), additional water content (7.5%, 11%, 14%, and 20%), and curing type (thermal, air, and water curing). S-GPC yielded rapid stiffening and high slump loss with high mechanical properties. The use of silica fume or fly ash or a mix of both enhanced workability, decreased rate of slump loss, and delayed setting time. The ACI 318 equation overestimates splitting tensile strength of FS-GPC. Key words: geopolymer concrete, ground granulated blast furnace slag, fly ash, silica fume. Cette recherche a porte sur l'utilite des cendres volantes et des fumees de silice dans la composition du beton geopolymere de laitier, et ce, par l'etude de la maniabilite (affaissement et perte d'affaissement), du temps de prise initial, du temps de prise final et des proprietes mecaniques du beton geopolymere de laitier (BGPL) (resistance a la compression, resistance a la traction par fendage, module d'elasticite) en plus du microscope electronique a balayage (MEB) et de l'analyse par rayons X. Les variables considerees comprenaient la teneur en cendres volantes (CV) en remplacement de laitier de haut fourneau granule et broye (LG) (0, 10, 20, 30 et 40 %), la presence de fumees de silice (FS) en remplacement de laitier, la concentration d'hydroxyde de sodium, NaOH, (molarite : 10,16 et 18 mol/L), la teneur en eau supplementaire (7, 5,11,14 et 20 %) et le type de cure (thermique, air et cure a l'eau). L'utilisation de fumees de silice ou de cendres volantes ou d'un melange de celles-ci a ameliore la maniabilite, reduit le taux de perte d'affaissement et retarde le temps de prise. L'equation ACI 318 surestime la resistance a la traction par fendage du beton geopolymere de laitier avec cendres volantes. [Traduit par la Redaction] Mots-cles: beton geopolymere, laitier de haut fourneau granule et broye, cendres volantes, fumees de silice., 1. Introduction The production of 1.0 t of ordinary portland cement (OPC) yields 11 of C[O.sub.2] (McCaffrey 2002). Geopolymer technology highly reduces the C[O.sub.2] emission to the atmosphere. Davidovites created [...]

Cellular concrete is a lightweight solid cementitious foam that is used mainly for thermal insulation and sound absorption. Either partially or wholly, when the Portland cement in the binder is replaced with ash, the environmental impact of the material is reduced. However, the resulting changes in the cell structure and their subsequent impact upon the physical properties of the material have not been well examined. In this study, cellular concrete was prepared from alkali activated fly ash binders and separately, from Portland cement binders blended with wood ash. The cell structure was photographed using laser confocal microscopy and the images were analyzed to quantify the cellular network in terms of the porosity and the fractal dimension of the porous phase. Alongside, the cellular concrete specimens were tested for their thermal constants and sound absorption. The results show that there was an increase in the fractal dimension and an associated drop in thermal conductivity for an increase in the porosity. Key words: alkali-activation, fly ash, foamed concrete, fractal dimension, sound absorption, thermal conductivity, wood ash. Le beton cellulaire est une mousse cimentaire solide et legere qui est principalement utilisee pour l'isolation thermique et l'absorption acoustique. Lorsque le ciment Portland dans un liant est remplace partiellement ou totalement par des cendres, l'impact environnemental du materiau est reduit. Cependant, les changements dans la structure cellulaire et leur impact subsequent sur les proprietes physiques du materiau n'ont pas ete bien examines. Dans cette etude, le beton cellulaire a ete prepare a partir de liants alcalins a cendres volantes et separement, a partir de liants de ciment Portland melanges avec des cendres de bois. La structure cellulaire a ete photographiee a l'aide de microscopie confocale laser et les images ont ete analysees pour quantifier le reseau cellulaire en termes de porosite et de dimension fractale de la phase poreuse. Parallelement, les specimens de beton cellulaire ont ete mis a l'essai pour leurs constantes thermiques et leur absorption acoustique. Les resultats montrent qu'il y a eu une augmentation de la dimension fractale et une baisse associee de la conductivite thermique pour une augmentation de la porosite. [Traduit par la Redaction] Mots-cles : activation alcaline, cendres volantes, beton de mousse, dimension fractale, absorption acoustique, conductivite thermique, cendres de bois., Introduction Foam concrete is a lightweight cementitious composite, cast to densities ranging from 300 kg/[m.sup.3] to 1900 kg/[m.sup.3] (Fouad 2006). An optimal balance between the mechanical strength and requirements of [...]

In this study, the simultaneous effects of both silanized coal fly ash (S-CFA) and nano/micro glass fiber (nGF) on fracture toughness and mechanical properties of vinyl ester (VE) resin filled with carbon fiber-based composite materials were investigated. The CFA was treated with (3-trimethoxysilyl) propyl methacrylate to introduce the methacryloxy groups into the surface of CFA, and was confirmed by using FTIR technique. The nGF and S-CFA with different weight ratios were well mixed with VE resin by using of high-speed mechanical stirrer, and ultrasonic technique before using as matrices for fabrication of carbon fiber-based composite materials via sheet molding compound (SMC) method and hot curing processing. Many characteristics of both cured VE resin composites and carbon fiber-based composite were examined such as mechanical properties, fracture toughness, and morphology. The results showed that by adding of both 0.1 wt% nGF and 1 wt% S-CFA into VE resin the tensile strength, tensile modulus, flexural strength, [K.sub.IC], impact strength as well as the Mode I interlaminar fracture toughness ([G.sub.IC]) of VE composites and carbon fiber based composites get optimum values and increased about 61.39%; 39.83%; 36.21%; 103.1%; 81.79%; 48.61%, respectively when compared with pristine materials., INTRODUCTION Along with epoxy resins, and unsaturated polyester resins, the vinyl ester (VE) resins are also considered as a common thermoset resin, and widely applied in the preparation of composite [...]

As a by-product from the incineration of municipal solid waste (MSW), fly ash usually contains mobile heavy metals that may engender severe pollution when reused. In this study, fly ash was solidified with cement and a chelating agent to immobilize these polluting elements. The possibility of using the solidified fly ash for pavement materials was also assessed through mechanical and environmental perspectives. According to the results, the strength of solidified fly ash was found proportional to both the cement/fly ash ratio and curing time. This indicated that the increase of fly ash loading reduced the concentration of products from cement hydration, and thus destroyed the structure of the products of hydration. With the increase of freeze-thaw cycles, the compressive strength of cement-stabilized fly ash decreased between days 7 and 14, and then increased between days 14 and 28. Subsequently, the finite element analysis showed that placing the solidified fly ash layer as a pavement material between an unbound base course and subgrade was beneficial to prolong fatigue life and reduce rutting distress of asphalt pavements. Finally, leachability of metals from the mixtures was tested, which showed that leaching concentration decreased as the cement/ash ratio, curing time, and chelating agent content increased. Key words: fly ash, freeze-thaw, cement-chelated stabilization-solidification, pavement material, finite element analysis. En tant que sous-produit de l'incineration de dechets solides municipaux (DSM), les cendres volantes contiennent generalement des metaux lourds qui peuvent engendrer une pollution grave pour la reutilisation. Dans cette etude, les cendres volantes se sont solidifiees avec le ciment et l'agent de chelation pour immobiliser ces elements polluants. La possibilite d'utiliser la matiere solidifiee de cendres volantes pour les materiaux de la chaussee a egalement ete evaluee par des moyens mecaniques et des perspectives environnementales. Selon les resultats, la resistance de cendres solidifiees a ete proportionnelle a la fois au rapport ciment-cendres volantes et au temps de sechage. Ceci indique que l'augmentation du chargement de cendres volantes a reduit la concentration de produits provenant de l'hydratation du ciment, et donc a detruit la structure des produits d'hydratation. Avec l'augmentation des cycles de gel-degel, la resistance en compression de ciment stabilise de cendres volantes a diminue de 7 a 14 jours, puis a augmente de 14 a 28 jours. Par la suite, l'analyse par elements finis a montre qu'en placant la couche de cendres solidifiees comme material de chaussees entre la couche de base non liee et le sol de plate-forme a ete benefique pour prolonger la duree de vie en fatigue et reduire la detresse de l'ornierage des chaussees d'asphalte. Enfin, la lixiviation des metaux des melanges a ete testee, ce qui a montre que la concentration de lixiviation diminuait alors que le rapport ciment-cendres, le temps de sechage et la teneur en agent de chelation augmentaient. [Traduit par la Redaction] Mots-cles: cendres volantes, gel-degel, stabilisation-solidification chelatee au ciment, materiau de chaussee, analyse par elements finis., Introduction Incineration is a commonly used method for managing the municipal solid waste (MSW) in the world. This is because it reduces the waste by about 70% in weight and [...]

The present work on the mechanical properties of [less than or equal to] 10 wt% fly ash additions in 2.5 wt% increments to recycled high-density polyethylene (RHDPE) synthesizes experimental data from three similar published reports. The present work shows, as a function of increasing fly ash addition level, maxima at the initial fly ash addition level of 2.5 wt% for the tensile elastic modulus (+25%) and tensile strength (+10%); a slight general increase in the yield stress (+6%); and significant general decreases in the yield strain (-61%), elongation at break (-92%), and Charpy impact strength (-55%). Combining these data with data for higher-level additions of fly ash (≤ 40 wt%/23 vol%) and cenospheres (≤ 39 vol%) to HDPE or RHDPE provides the basis for design parameters and a generalized model for the interpretation of failure of composites of hard brittle spherical dispersant additions in ductile polymeric matrices. The relevant load-extension plots are characterized by three behavioral regions: ductile deformation (dispersion strengthening and stress concentration), crazing (debonding and cavitation), and brittle failure (fibril failure). The locations of these regions and their transitions are a function of five dependent variables: dispersant volume, dispersant particle size, intrinsic flaw size (viz., dispersant size), generated flaw size (viz., void size), and interfacial bond strength and associated load transfer., INTRODUCTION Fly ash, a waste product from coal-fired power plants, represents a large-scale problem for waste disposal because as much as ~750 million tons are produced per annum but only [...]

The effects of rice husk biochar (BC) and coal fly ash (FA) on growth and yield of rice and soil properties were investigated in a lowland rice soil. All growth parameters and yield were positively influenced by the integrated application of BC, FA and chemical fertilisers compared with sole application of chemical fertilisers. Yield increase was 16.4% when BC+FA was applied together with 50% of the recommended dose of nitrogen (N) compared with the recommended dose of N, phosphorus and potassium (NPK). Post-harvest soil analysis suggested that BC and FA both act as a supplier, as well as a reservoir of nutrients. Accumulation of heavy metals in soil and plant parts after harvest was below the toxicity threshold for plants and humans. There was also no significant change in microbial population compared with the initial soil. Therefore, combined application of BC and FA supplemented with chemical fertilisers could be recommended to improve soil fertility and crop productivity without affecting the soil quality. Additional keywords: fertilisers, heavy metals, microbes, nutrients, rice husk. Received 12 October 2015, accepted 20 November 2015, published online 3 June 2016, Introduction Utilisation of agricultural and industrial wastes is a worldwide concern. Among the different agro-wastes, 116 million tonnes of rice husk is produced annually by more than 75 countries (FAO [...]

Very-early-strength latex-modified concrete (VES-LMC) was developed for rapid repairs of distresses in concrete bridge decks and pavements, with the emphasis on early-age strength gain so that the repaired bridges and pavements can be opened to traffic within the time frame required in the specifications. However, there are two main concerns in the use of VES-LMC--early-age cracking and poor air void structure. The main objective of this study was to further improve VES- LMC to minimize early-age cracking and improve freeze-thaw durability, which included the use of fine fly ash (FFA) and calcium hydroxide (CH). Laboratory experiments were conducted on VES-LMC materials with cement replaced with FFA as well as CH, and various tests performed. Early-age drying shrinkages of VES-LMC containing both FFA and CH in the amounts evaluated in this study were smaller than that of VES-LMC with no replacements. It is expected that the use of FFA and CH in the range evaluated in this study will reduce the cracking potential of VES-LMC. Overall, the replacement of cement with FFA and CH improved the characteristics of entrained air void system, which will enhance the durability of VES-LMC against freeze-thaw damage. Scanning electron microscope and energy dispersive spectroscopy analysis indicate the primary mechanism of the generation of small sized air voids in concretes containing adequate amount of FFA and CH is the gas formation reaction between citric acid solutions and CH during concrete mixing. It is expected that the inclusion of adequate amounts of FFA and CH in VES-LMC will improve the performance of repaired bridge decks and pavements in terms of reduced cracking and improved freeze-thaw durability. Key words: air void structure, freeze and thaw, fine fly ash, rapid setting concrete. Le beton modifie au latex a prise ultra-rapide (BML-PUR) a ete concu pour reparer les dommages dus a l'usure sur les tabliers de pont et revetements en beton. Sa capacite a durcir rapidement a ete mise en avant, car elle permettait de rouvrir a la circulation les ponts et chaussees repares dans les delais requis. Cependant, l'utilisation d'un tel beton pose deux principaux problemes: l'apparition de fissures prematurees et une structure caracterisee par une mauvaise repartition des vides interstitiels. L'objectif principal de la presente etude a ete d'ameliorer les performances de ce type de beton afin de reduire au minimum l'apparition de fissures prematurees et de renforcer sa resistance dans le temps au gel-degel, a l'aide notamment de cendres volantes (CV) et d'hydroxyde de calcium (HC). Des essais en laboratoires ont ete realises sur des echantillons de BML- PUR dans lesquels le ciment a ete remplace par des CV et de l'HC et d'autres types d'essais ont effectues. Les retraits de sechage premature du BML-PUR contenant a la fois des CV et de l'HC, dans les quantites determinees dans la presente etude, etaient moins importants que ceux observes sur le BML-PUR uniquement compose de ciment. On s'attend a ce que l'utilisation de CV et d'HC, dans les intervalles de teneurs definis dans la presente etude, aura pour effet de reduire le risque de fissuration du BML-PUR. D'une maniere generale, le remplacement du ciment par des CV et de l'HC a permis d'ameliorer les caracteristiques des occlusions d'air formant les vides interstitiels a l'interieur du beton, ce qui renforcera la resistance dans le temps du BML-PUR au gel-degel. Une analyse au microscope electronique a balayage et une analyse dispersive en energie montrent que la reaction entre les solutions d'acide citrique et l'HC, qui se produit durant la preparation du melange de beton, constitue le principal mecanisme de formation des vides interstitiels de petite taille dans les betons contenant des quantites adequates de CV et d'HC. On s'attend a ce que l'ajout de quantites appropriees de CV et d'HC dans le BML-PUR ameliore a l'avenir les performances des tabliers de pont et revetements repares, en reduisant la fissuration du beton et en renforcant sa resistance dans le temps au gel-degel. [Traduit par la Redaction] Mots-cles: repartition des vides interstitiels, gel et degel, cendres volantes, beton a prise rapide., 1. Introduction The most frequent and serious distress type reported in jointed plain concrete pavement (JCP) in South Korea is spalling at transverse and longitudinal joints, primarily due to freeze [...]

Increased temperatures and rainfalls will give more settlements and less bearing capacity in gravel roads, which will have implications for the forestry. Pulp mill fly ash without additives was used for stabilizing the road base of a low-volume gravel road. A two-year monitoring of the road was conducted, including measurements of achieved ash content, density, water infiltration capacity, and load bearing capacity. The results showed that the ash-stabilized sections performed better than conventionally upgraded sections and also achieved increased bearing capacity over time. Hydration of the fly ash increased the stiffness and decreased the permeability of the road base. The differences were more pronounced during spring thaw. Best performance was achieved in the section with thicker ash stabilized layer. Key words: unpaved roads stabilization, forest road, spring thaw, biofuel ash, field, bearing capacity, recycling. L'augmentation des temperatures et des precipitations provoquera un tassement plus important des routes de gravier et une diminution de leur capacite portante, ce qui aura des repercussions sur la foresterie. Des cendres volantes issues d'usines de pate a papier sans additifs ont ete utilisees pour stabiliser la couche de base d'une route de gravier a faible trafic. Un suivi a ete effectue sur deux ans, comprenant des mesures du contenu en cendres restant, de la densite, de la capacite d'infiltration d'eau et de la capacite portante. Les resultats ont montre que les portions de route stabilisees avec de la cendre offraient de meilleures performances que celles renovees de maniere traditionnelle et qu'elles presentment egalement une meilleure capacite portante au fil du temps. On a aussi constate que l'hydratation des cendres volantes augmentait la rigidite et diminuait la permeabilite de la couche de base. Les differences observees etaient moins importantes durant le degel printanier. Les meilleures performances ont ete atteintes dans la portion de route ou la couche de base stabilisee avec de la cendre etait la plus epaisse. [Traduit par la Redaction] Mots-cles: stabilisation des routes non asphaltees, route forestiere, degel printanier, cendres de biomasse, terrain, capacite portante, recyclage., Introduction Many gravel roads in Sweden suffer from reduced bearing capacity for part of the year, mainly during spring thaw when the road layers are weakened by water accumulation. In [...]