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Since the beginning of the 1990s, many researchers and several organizations concerned with development- and environment-related issues have devised methods to evaluate sustainable development at national and international scales. To that effect, they have identified sustainable development indicators. To date, however, very little work has focused on industrial activities. This paper presents a semi-quantitative method allowing evaluation of the environmental aspect to sustainable development, with an application on the environmental performance of the effluent treatment procedure of a paper mill. Eight environmental indicators for sustainable development are considered for evaluation. These indicators are linked to the strategic requirements for sustainable development as stated in the Bruntdland Commission. They are also acknowledged by many authors and organizations. The environmental performance evaluation on the effluent treatment procedure of the paper mill under study shows that this activity meets a relative degree of sustainability. This evaluation allows the identification of the strengths and weaknesses of the effluent treatment with respect to sustainable development.Key words: indicators, sustainable development, measure, environmental performance, biologic treatment, effluents, paper mills.[Journal translation]Depuis le début des années 1990, plusieurs chercheurs et différents organismes préoccupés par les questions de développement et d'environnement mettent au point des méthodes pour évaluer le développement durable à l'échelle nationale ou internationale. Pour ce faire, ils ont identifié des indicateurs de développement durable. Cependant, très peu de travaux se sont concentrés à date sur les activités industrielles. Cet article présente une méthode semi-quantitative permettant l'évaluation du volet environnemental du développement durable avec application à la performance environnementale de la filière de traitement des effluents d'une papetière. Huit indicateurs environnementaux de développement durable sont retenus pour les fins de l'évaluation. Ces indicateurs sont rattachés aux impératifs stratégiques de développement durable énoncés par la Commission Bruntdland. Ils sont aussi reconnus par plusieurs auteurs et organismes. L'évaluation de la performance environnementale de la filière de traitement des effluents de la papetière étudiée montre que cette activité rencontre un degré relatif de soutenabilité. L'évaluation permet d'identifier les forces et les lacunes que comporte la filière de traitement des effluents en regard du développement durable.Mots clés : indicateurs, développement durable, mesure, performance environnementale, traitement biologique, effluents, papetières. [ABSTRACT FROM AUTHOR]

This paper deals with the shear strengthening of reinforced concrete (RC) beams using externally bonded fiber-reinforced polymer (EB FRP) composite materials. The first part of the paper reviews the evolution of North American codes and standards for the shear resistance of RC beams strengthened with EB FRP composites, whereas the second part provides a comprehensive analysis of the major parameters influencing the contribution of FRP to shear resistance. It also presents a comparison of the predictions of current design standards (ACI 440.2R 2017; CSA/S6 2019; CSA/S806 2012; fib -TG9.3 2001) with the results of experimental tests reported in the literature. The study shows that major parameters influencing the shear behaviour have received little attention. These parameters include in particular: (i) the presence and ratio of internal transverse steel reinforcement and (ii) the number of EB FRP plies (layers). This may explain the observed discrepancies between the prediction models of existing equations for shear resistance and the results obtained from tests. Consequently, a database extracted from the experimental studies was developed as part of this study. The results obtained highlight and confirm the existence of an interaction between the EB FRP composites and the internal transverse steel reinforcement with regard to shear resistance of RC beams. They also show the existence of an optimal FRP stiffness beyond which there is no substantial gain in resistance attributed to the EB FRP. [ABSTRACT FROM AUTHOR]

The permanent deformation of the road subgrade soil accumulated during passage of the cyclic loads is mainly due to the post-compacting and plastic flow mechanisms according to a study by the National Cooperative Highway Research Program in 2004. The main objective of the paper is to develop a relationship between the parameters a an d b of a power model and the usual physical properties of subgrade soils. The parameters a and b are assumed to represent the post-compacting and plastic deformation, respectively. Highlighting the link between the parameters a and b and the mechanisms of permanent deformation was the basic assumption which helped developing correlations. Data collected on nine different samples of soils characterized and having undergone cyclic triaxial tests permanent deformation were used to develop relationships. A distinction was made between the relationship parameter for clay and sandy soils. Indeed, clay soils with lower air permeabilities behave differently when compared to post-compaction sandy soils. However, a single relationship was developed for the parameter b, because the observed behavior appears similar for clay and sandy soils. Both correlations have coefficients of determination about 0.6. Also, comparison of the measured and predicted permanent deformation was done on the clay of St-Narcisse and sand of Fossambault. The results are generally good, despite a case of discrepancy observed. [ABSTRACT FROM AUTHOR]

Eight suggestions for a public action and a methodology to apply them have been described in a complementary paper, to incite the professionals from Quebec involved in the sustainable stormwater drainage management to target clear objectives. The present paper reports a case study where these eight suggestions were applied in a developing residential sector located in a Quebec municipality, following the proposed methodology. The main objective of this paper is to show the feasibility of some selected Best Management Practices (BMP). The brief economical analysis performed in the study shows that integration of some applicable BMP in Quebec cities seems to be cost effective, when clear objectives are targeted. Nevertheless a deep analysis is still necessary to identify all feasible BMP designed to improve the urban drainage management and to determine the real costs linked to the new techniques investment. [ABSTRACT FROM AUTHOR]

This paper proposes an approach to represent the dynamic behaviour of a river through reliable transfer functions. This approach was applied to the Péribonka River, in Quebec. The paper describes the design of these functions between the Chutes-des-Passes and Chute-du-Diable power plants, including the Péribonka power plant under construction (at the time this paper was written). The FLDWAV software models the flows under various production conditions. The model was calibrated over several summers using data from the Péribonka River gauging station. The multiple flow transfer functions obtained under various flow conditions and water levels were simplified for use in production optimization. They were validated on each river section. Tests show these functions correlate well with open water flow dynamics. However, these flow transfer functions are not recommended for winter water flow simulation. Une méthode pour représenter les comportements dynamiques d’une rivière par des fonctions de transfert fiables est proposée. Elle est appliquée à la rivière Péribonka (Québec). L’article détaille la création de ces fonctions entre les centrales Chutes-des-Passes et Chute-du-Diable, incluant la centrale Péribonka en construction (lors de la rédaction de cet article). Le logiciel FLDWAV modélise les écoulements sous des conditions de production variées. Le modèle a été étalonné sur plusieurs saisons estivales grâce aux stations hydrométriques de la rivière Péribonka. Les multiples fonctions de transfert de débit (FTD) obtenues pour diverses conditions de débit et de niveau d’eau ont été simplifiées en vue de leur usage en optimisation de la production. Elles ont été validées sur chaque tronçon de la rivière. Les tests montrent qu’elles respectent bien la dynamique des écoulements en eau libre. Toutefois, l’utilisation des mêmes FTD n’est pas recommandable pour simuler l’écoulement de l’eau en période hivernale. [ABSTRACT FROM AUTHOR]

Quebec's Dam Safety Act demands a safety assessment for all dams, whatever their capacity. The capacity only affects the detail level of the study to qualify the consequences of a potential dam failure, and thus determine the dam's classification. In practical terms, it is difficult to qualify the consequences of a failure flood if a complete hydraulic calculation of the failure flood is not performed. If consequences are not significant, this complicated specialized work can be deemed unnecessary by the dam owner, who normally has to defray the cost. This paper compares results of a complete dynamic calculation to those of three "simplified" methods. It shows, in two specific cases, that flow depth errors are significant, even after eliminating the greater part of this error generated by the discharge evaluation at the breach. The paper also shows that work involved when using "simplified" methods is not significantly decreased with relation to the work required for the complete calculation when time comes to interpret the data to assess correctly the consequences of a possible dam failure. [ABSTRACT FROM AUTHOR]

This paper presents results of an investigation on the shear strengthening of reinforced concrete (RC) beams with externally applied fibre reinforced polymer (FRP) composites. The first part of the study reviews and synthesizes the state of the art in the subject. Also, the requirements and recommendations specified in the Canadian CSA S806-02 standards, the American ACI-440 guidelines, as well as the European fib TG9.3 recommendations are compared with the test results reported in the literature so far. This part of the study indicates that the major parameters involved in the behaviour of RC beams strengthened in shear with FRP were not fully investigated. This can explain the observed discrepancies between the resistance values predicted by the codes and guidelines, and those obtained by tests. This has been the main impetus to carry out an experimental investigation, which is the subject of the second part of this paper. The objective of this experimental investigation was to study the influence of the following parameters on the performance of RC beams strengthened in shear with FRP composites: (i) the FRP ratio, (ii) the transverse steel reinforcement ratio, and (iii) the type of beam (deep versus slender). Results clearly showed the interaction between the FRP composite and the internal transverse steel reinforcement in the shear resistance mechanism. Results also showed the influence of the type of beam on the gain due to FRP on the carrying capacity of the beam. [ABSTRACT FROM AUTHOR]

The validity of dam failure studies is based on the appropriateness of the expected failure mode. Failures of earth-fill structures show the importance of the choice of breach parameters for failure evaluation and consequences. This paper summarizes the state of the possibilities for forecasting the breach and the resulting hydrograph in the downstream valley. It describes the most current methods, applies them on a failure case observed in the Saguenay region, Province of Québec, and compares the results. Considering the large uncertainty margin on the results, the paper allows one to understand why breach forecasting must not, in the current state of knowledge, be part of the safety study process, and that it is preferable to stay with a definition for breach based on a rule intelligently applied with respect to the case, the structure, and its composition.Key words: dam failure, dam breach, erosion, forecasting, flood of failure, earth-fill dam.[Journal translation]La validité des études de rupture de barrage repose sur la fiabilité du mode de rupture appréhendé. Les ruptures d'ouvrage en terre et enrochement montrent l'importance du choix des paramètres de brèche dans l'évaluation et les conséquences de rupture. Ce présent article résume l'état des possibilités de prévision de la brèche et de l'hydrogramme transmis dans la vallée en aval. Il décrit les méthodes les plus courantes, les applique à un cas de rupture observé au Saguenay en juillet 1996 et compare les résultats. À la lumière de la grande marge d'incertitude observée dans les résultats, il permet de comprendre pourquoi la prévision de la brèche ne doit pas dans l'état des connaissances actuelles faire partie de la démarche des études de sécurité et qu'il vaut mieux s'en tenir à une définition de celle-ci basée sur une norme appliquée intelligemment en fonction du cas, de l'ouvrage et de sa composition.Mots clés : rupture de barrage, brèche de barrage, érosion, prévision, crue de rupture, barrage en terre. [ABSTRACT FROM AUTHOR]

Fatigue is considered the main damaging phenomenon at « average » temperature in flexible pavement structures. A fatigue damage model is thus the first step in applying a mechanistic-empirical approach to sizing. This paper highlights the main elements of fatigue models in order to thoroughly understand the various calculation tools available for a mechanistic-empirical sizing application. The signification of the various coefficients of the models is described and interrelations are established. An analysis is proposed to improve the representativeness of the fatigue life span law of the material. All calculation tools for mechanistic-empirical sizing use the Wöhler fatigue curve. Both fatigue curve coefficients are at the core of the models and describe the specific performance of the tested bituminous material families. Processing the results of a classic fatigue test to exclude biased effects will substantially modify the values of these two coefficients. It is demonstrated that the life spans determined from raw results are overestimated. [ABSTRACT FROM AUTHOR]

Flow gauge data - and even rainfall data - are quasi unavailable for small watersheds as those on which hill ponds are constructed. The objective of this paper is to present a regional statistical approach aiming at estimating the rainfall characteristics related to these small watersheds. The regional approach allows estimating the coefficient of variation of the average annual rainfall, choosing the statistical distribution of the interannual variability as well as estimating the maximal daily rainfall at different return periods; all of these statistics using mainly the average annual rainfall along with geographic characteristics of the hill ponds location and their watersheds. The methodology is applied in an area of 43 000 km2 in the North East of Algeria. The developed statistical relationships are robust and reliable as shown by cross validation checking, which allows using them for preliminary design purposes of hill ponds. [ABSTRACT FROM AUTHOR]

The objective of this paper is to classify the most adequate frequency laws to estimate the extreme floods in northern Algeria in the large Isser, Chellif and Côtiers Algérois Ouest drainage basins. The first step is to determine which laws could best represent the data used. The second step is to classify selected laws using various chosen criteria such as: BIC, AICc, and Schwartz criterion based on a priori and a posteriori probability concepts. The classification in this step is carried out using the unique information collected from observing each site, then working in the information collected from adjoining sites. Results show the prominence of the Gamma distribution. [ABSTRACT FROM AUTHOR]

As waste management systems are constantly evolving, each and every decision taken today will influence future actions. Among the problems encountered, the selection of a site to implement new facilities, no matter their type, is a significant issue given the related social, economic and environmental constraints. Decision makers thus require new tools to compare the various options available and to assess the impacts on the system. The mathematical approaches currently used to solve the land location issues are inadequate for waste management. In particular, these approaches cannot consider all impacts of waste management nor the route characteristics (length, traffic constraints, capacity). To remedy these shortcomings, this paper presents effective waste management as a decision-making tool for land management, especially location issues. Two case studies are presented to illustrate the benefits of the proposed approach. Les systèmes de gestion des déchets étant en constante évolution, chacune des décisions prises aujourd'hui aura une influence sur les actions futures. Parmi les difficultés rencontrées, la sélection d'un site pour l'implantation de nouvelles installations, quelle que soit leur nature, représente un enjeu majeur en raison des contraintes sociales, économiques et environnementales qui s'y rattachent. En conséquence, les décideurs réclament de nouveaux outils qui leur permettront de comparer les différentes options qui s'offrent à eux et d'en évaluer les impacts sur le système. Actuellement, les approches mathématiques utilisées pour résoudre les problèmes de localisation sur un territoire sont inadéquates pour la gestion des déchets. Notamment, ces approches ne permettent pas de considérer l'ensemble des impacts attribués à la gestion des déchets ainsi que les particularités associées aux trajets (longueur, contraintes de circulation, capacité). Dans le but de corriger ces lacunes, le présent article porte sur l'utilisation de la gestion dynamique des déchets (GDD) comme outil d'aide à la décision pour la gestion territoriale, et plus particulièrement pour les problèmes de localisation. Afin de démontrer les avantages de l'approche proposée, deux études de cas sont également présentées. [ABSTRACT FROM AUTHOR]

New technologies based on seismic isolation are gaining popularity among engineers given the savings on construction costs. The long-term advantage of these technologies preserve the serviceability of the structure after an earthquake and eliminate the cost of reconstruction. This advantage is critical for 'emergency' bridges, required to remain operational after an earthquake. The present article examines a method of isolating the foundation of existing bridges as part of a seismic retrofitting effort. This approach is supported by the increasing interest in this method, especially since its adoption by the Canadian standards and due to the fact that engineers are not too familiar with non-linear dynamic design methods. Another source of motivation is the opportunity to apply this technique to the refection of a few Quebec bridges. The steps of the antiseismic calculations as well as the results of non-linear analyses pertaining to the Madrid Bridge are presented and discussed. This paper may become a useful tool for engineers and their projects of retrofitting existing bridges. Les nouvelles technologies basées sur l'isolation sismique connaissent un intérêt grandissant parmi les ingénieurs, compte tenu de l'économie sur le coût de la construction de l'ouvrage qu'elles offrent. Elles présentent également un avantage indéniable à long terme étant donné qu'elles préservent la fonctionnalité de l'ouvrage après séisme et éliminent le coût de reconstruction. Cet avantage revêt une importance capitale pour les ponts dits de secours qui doivent demeurer en service après le séisme. Cet article présente une méthodologie relative à l'isolation de la base des ponts existants dans un contexte de mise en conformité sismique. Cette démarche est motivée par l'intérêt grandissant de cette méthode, notamment depuis son adoption par la norme canadienne d'une part et d'autre part par le fait que les ingénieurs praticiens sont moins familiers avec les méthodes dynamiques non linéaires de conception. L'opportunité offerte aux auteurs de mettre en application cette technique pour la réfection de quelques ponts au Québec est une autre source de motivation. Les étapes de calcul parasismiques sont pourvues, et les résultats des analyses non linéaires relatives au pont Madrid sont présentés et discutés. L'article est destiné aux ingénieurs praticiens qui y trouveront un outil utile pour leurs projets en réhabilitation de ponts existants. [ABSTRACT FROM AUTHOR]

The present paper analyzes the influence of the reservoir drawdown submodel on the numerical results of a dam break analysis. A static representation, which takes into account the storage curve, is compared with a dynamic representation based on the Saint-Venant equations along with the real bathymetry of the reservoir. The comparison is based on breach hydrograph, maximum water level, inundated area, and wave arrival time in the valley downstream. It appears that the difference in level attained is maximal in the vicinity of the dam, particularly for maximum level and inundated area, and that this difference decreases as the distance from the reservoir increases. The analysis performed has shown that the static representation overestimates the maximum depth and inundated area in a proportion that can reach 20%. The use of dynamic representation can reduce this overestimation by 30%-40%. In the absence of bathymetric data in the reservoir, a dynamic model based on a synthetic trapezoidal reconstruction of the storage curve is examined. It appears that this model can significantly reduce the uncertainty associated with the static model. Le présent article analyse l’impact du modèle de représentation de la vidange du réservoir sur les résultats de modélisation numérique de rupture de barrage. Le modèle à représentation statique à l’aide de la courbe d’emmagasinement est comparé à celui à représentation dynamique à l’aide d’un modèle de Saint-Venant utilisant la bathymétrie du réservoir. La comparaison est basée sur l’hydrogramme à la brèche, les niveaux maximaux, les surfaces inondées et les temps d’arrivée de l’onde à l’aval pour trois cas de réservoir de tailles différentes. Il ressort que la différence entre les deux modèles de représentation est maximale à la brèche et à l’aval immédiat du barrage, notamment pour le niveau maximal et la surface inondée, et qu’elle s’estompe plus loin à l’aval. L’analyse des résultats de simulation des cas étudiés montre que le modèle statique surestime les rehaussements atteints ainsi que la surface inondée à l’aval du barrage dans une proportion qui peut atteindre 20 %. L’utilisation d’un modèle dynamique de représentation du réservoir peut permettre de réduire de 30 % à 40 % ces surestimations. En l’absence de données bathymétriques du réservoir, la reconstitution de données synthétiques reproduisant la courbe d’emmagasinement pour servir de base à un modèle dynamique du réservoir est examinée. Il apparaît que cette solution peut réduire de façon appréciable l’incertitude due à la représentation statique. [ABSTRACT FROM AUTHOR]

The non controlled management of runoff stormwater volumes may cause the quality degradation of water tables and water surfaces. An investigation conducted in 2007 on the stormwater management in Quebec shows the existence of certain gaps in the design of the stormwater networks, when more and more expectations are coming from citizens and sustainable development requirements. It becomes therefore urgent to set up in Quebec a new stormwater management approach based on sustainable and integrated solutions. The present paper lists a brief state of the art in Quebec regarding the stormwater issue. Also it analyzes the Best Management Practices (BMP) applicable in Quebec and it describes a strategy to control the stormwater runoff volumes. Eight suggestions for a public action in the context of a sustainable development are developed. A nine-step methodology process is presented to show how professionals involved in environment issues may apply these eight suggestions. [ABSTRACT FROM AUTHOR]

This paper presents a comprehensive review of the new provisions for the design of coupled shear walls in Canadian seismic zones. It follows major revisions that were incorporated in the National Building Code of Canada 2005 (NBCC 2005) and in the Canadian standard Design of concrete structures (CSA A23.3-04), which were due, in particular, to the adoption of a new Canadian map of seismic risk. The present study is intended to address recurring confusions in current practice and the difficulties expressed in the application and interpretation of the new NBCC 2005 and CSA A23.3-04 provisions. A design flowchart is thus proposed as a practical guide, describing, step by step, the required verifications at each stage of coupled shear walls calculation. Finally, to demonstrate the applicability of these new provisions, a numerical example is detailed, following the presented design flowchart. [ABSTRACT FROM AUTHOR]

Sewer networks represent an important asset that requires good management according to a long-term integrated policy, which should take into account the state of sewer pipes, their environment, and budgeting constraints. In this scope, a good knowledge of the asset stock ensured by an inventory and data gathering is necessary. The asset considered in this article is the sewer pipes, with a diameter of less than 1200 mm. The state of the sewers is assessed according to closed circuit television (CCTV) inspections obtained by special cameras. The inspections allow us to describe the state of pipes according to observed defects, but do not give a tool for decision aiding for rehabilitation or renewal. In order to exploit available data for help in decision-making, we propose to use the methodology defined in the French project for rehabilitation of sewer networks RERAU (2000-2004) that suggests defining a set of dysfunction indicators according to observed defects following CCTV inspections. We use the defined dysfunctions as decision criteria with the help of the multicriteria approach Electre-tri for implementing the sorting procedure of sewers into specific categories according to their state of deterioration . Our study was achieved on a sample of sewer pipes in Alsace, France. The current paper details the approach for sorting the sewers and defining guidelines for the categorization of sewers according to their level of deterioration. [ABSTRACT FROM AUTHOR]

This paper describes the second phase of our research project on the influence of the composition parameters on the behaviour of unset and hardened self-compacting concrete (SCC). It studies the impact of the water/cement ratio and the fines/cement ratio on the behaviour of hardened SCC. Several tests were carried out, such as surface settlement, L box, sieving, bleeding, mechanical strengths, free shrinkage (drying shrinkage and autogeneous shrinkage) and a microstructure study (mineralogical characterization, pore space distribution), to better understand the roles of the various possible SCC components made with local materials and to identify the mechanisms governing shrinkage. We highlighted the role of the pore network and the microstructure of the hydrates. Results show good SCC optimization potential in Algeria. Our study helped develop several SCC formulations meeting the rheological criteria (good deformability, less bleeding, no segregation, better mechanical performance). [ABSTRACT FROM AUTHOR]

The mechanical behavior of natural fiber reinforced concrete (NFRC) depends mainly on the bond between the cement matrix and the fibers. Such a bond also has a certain influence on the type of failure displayed on the fibers of NFRC. The research reported in this paper deals with natural fibers of lechuguilla (Agave lecheguilla). Material characterization tests were performed on these natural fibers, such as: determination of chemical composition, morphology, porosity, and absorption of water. Tension and bending strength of the composite were tested. The fiber-cement matrix interface was studied using a stereoscope to evaluate the effect of the alkaline environment on specimens with different water/cement (W/C) ratios. An increase on the tension and bending strength of the composite material was observed as the length of the fibers increased and their volume decreased. The test series results have shown that the main type of NFRC failure was due to fibers pullout. The bond between the cement matrix and the fibers is affected by the volumetric changes and also by the relatively high water absorption; however, the bond can be improved considerably by superficial chemical treatment of fibers with xylene solutions and also by using low W/C ratios. [ABSTRACT FROM AUTHOR]

In Amazonia, because the small catchments are ungauged, it is not possible to analyse them, for example, for hydroelectric power production. Thus, the objective of this paper is to study the transferability of a rainfall-runoff model to simulate flow duration curves for the production of hydroelectric power. The approach is based on the transfer of the impulse response of a model calibrated on two gauged catchments, allowing the evaluation approach permutation between these two catchments. We have, respectively, 7 years and 2 years and 2 months of rainfall and runoff data for these catchments. A sensitivity analysis of the transferability calibration to the sample size is carried out to determine the shortest flow period gauged on the receptor catchment, which produces results comparable to those calibrated with the maximum samples size. This analysis evaluates fieldwork on the ungauged sites of the region. En Amazonie, les petits bassins versants ne disposent pas de données de débit, ce qui empêche l’étude de ces bassins, par exemple, pour des fins de production d’énergie hydroélectrique. Ainsi, l’objectif de ce travail est d’étudier la transférabilité d’un modèle pluie-débit pour simuler les débits classés en vue d’une planification de la production hydroélectrique. L’approche est basée sur le transfert de la réponse impulsionnelle d’un modèle étalonné sur deux bassins jaugés permettant l’évaluation de la permutation de l’approche. Sur ces bassins test, on dispose respectivement de 7 ans et de 2 ans et 2 mois de données de pluie et de débit. L’analyse de sensibilité de l’étalonnage de la transférabilité détermine la taille minimale de la série de débits mesurés sur le bassin cible qui assure encore des résultats comparables à ceux étalonnés avec les échantillons de taille maximale de débits. Celle-ci évalue l’effort de mesures sur des sites non jaugés de la région. [ABSTRACT FROM AUTHOR]

To be cost effective, surface repairs carried out on concrete structures have to perform satisfactorily over a sufficient period of time. Among the factors that can affect the durability of concrete repairs, drying shrinkage is certainly one of the most significant. The use of shrinkage-compensating concrete (SCC) made with expansive binders thus represents an attractive alternative for achieving durable repairs. This paper presents the results of a study aimed at evaluating the potential use of repair concretes made with type K cement. The experimental program was designed to characterize the frost durability of SCC, to establish whether the bond between SCC and an old concrete substrate is affected by the expansion process, and, finally, to evaluate the efficiency of the prestressing effect generated through the bond. Although some aspects still need to be studied, the reported results are quite promising. Pour être rentables, les réparations superficielles effectuées sur les infrastructures en béton de ciment doivent présenter un niveau de performance adéquat pendant une durée minimale. Parmi les facteurs pouvant affecter la durabilité de ce type d’interventions, le retrait de séchage constitue sûrement l’un des plus importants. L’utilisation de bétons à retrait compensé (BRC) fabriqués avec des liants expansifs constitue une alternative intéressante pour la mise en œuvre de réparations durables. Cet article présente des résultats d’une étude visant à évaluer le potentiel d’utilisation des bétons de réparation fabriqués avec un ciment type K. La démarche expérimentale visait principalement à caractériser la durabilité au gel des BRC, à déterminer si l’adhérence d’un BRC sur un substrat de béton ancien est altérée par l’expansion et, enfin, à évaluer l’efficacité de l’effet de précontrainte mobilisé par adhérence. Bien qu’un certain nombre d’aspects demeurent à étudier, les résultats obtenus se révèlent prometteurs. [ABSTRACT FROM AUTHOR]

Biodiesel, a fuel derived from animal or vegetable oil and fats, is presented in this paper. More specifically, its physico-chemical properties as well as the raw materials and existing standards are described. The advantages, limitations, and future of biodiesel are discussed. Biodiesel offers significant environmental advantages over petrodiesel: its combustion produces fewer atmospheric emissions of pollutants and greenhouse gases; in addition, it biodegrades easily and does not present a major risk during storage. On the other hand, the substitution of biodiesel for petrodiesel usually causes an increase in fuel consumption by engines. In addition, according to various estimates, the price of biodiesel is higher than that of petrodiesel. Nevertheless, biodiesel is easy to produce and, with the anticipated decline in stocks of fossil fuels, it constitutes an interesting substitute that should become increasingly used in the next decade. [ABSTRACT FROM AUTHOR]

This paper presents an experimental study of the effect of adding recycled cellulose fibres on physical, thermal, and mechanical properties of lightweight concrete composites. Results show an important decrease of density and thermal conductivity with an increase of fibre content. Compression and flexural strength decreased with fibre content, but remained within the standard range for hollow non-load-bearing concrete masonry (ASTM C109/C 109-95) for the maximum fibre content (15%). [ABSTRACT FROM AUTHOR]

This paper examines models for the errors in forecasts of river and (or) watershed flows produced by the PREVIS forecasting system, which is used by Alcan, among other companies. We analyzed the following statistical models: generalized Pareto, Laplace, and Gaussian distributions, depending on the flow value forecasted by PREVIS. These models enable us to quantify the precision of the forecasts produced by PREVIS, as well as the risk of seeing the flow exceed a certain critical threshold, given the forecasted flow. [ABSTRACT FROM AUTHOR]

This paper presents the EROBAR numerical model on breach formation in earth-fill dams during an overtopping flow. Hydraulics of flow over an earth-fill dam is considered as the basis for the comprehension of the breach formation process. To this will be added the mastery of the erosion mechanism and of widening of the breach canal. As the breach formation process in an earth-fill dam is very complex, the EROBAR model was the object of a two-step formulation, with the two steps joined later. The first step deals with the flow hydraulics, vertical erosion, and longitudinal evolution of the profile of the dam. The second step introduces the widening of the breach, based on the instability of the breach slope. After the two formulations were joined and validated, the EROBAR model was applied to the experimental dyke, to several homogenous earth-fill dams with or without protection, and to zoned dams. [ABSTRACT FROM AUTHOR]

Life support networks are vital structures, as they are significant in size and essential in nature for the entire society. A network failure may thus involve serious consequences. The analysis of the needs of those in charge of emergency measures has established that the behaviour of life support networks had to be studied not only for extreme events but also for all possible situations of failure. In this context, the role of civil engineers is crucial, since they must assure the safety of infrastructures from design to dismantling. The proposed approach consists of characterizing networks according to the importance and efficiency of their missions, operations, and essential infrastructures. This allows approaching network vulnerabilities from an exhaustive and global perspective. Based on the degree of efficiency of a mission, it is possible to identify the dysfunctioning operations and infrastructures, from which the internal and external causes of faults or failures could be defined. Instead of starting from a hazard and asking the question "What-if", as is currently done, this new approach aims at determining the vulnerabilities of a network by asking the question "Why". Once the potentialities of failures are defined, it will be possible, by using a global method of fusion, to determine the vulnerabilities of the various components of a life support network (missions, operations, infrastructures). This paper describes this new approach and the required criteria for the development of a global methodology for the assessment of anthropic hazard. Our article illustrates this approach with an application to a hydroelectric facility. [ABSTRACT FROM AUTHOR]

Log-linear models are frequently used in hydrology, especially for the regional estimation of flood volumes based on the physiographic data of a set of basins. A log-linear model describes a linear relationship between the log of a dependant variable and independent variables which are functions of parameters, of which the value remains to be determined. It is determined by using a set of basins with known values of dependant and independent variables. The model is then used to obtain a prediction for the dependant variable logarithm of a basin of interest, based on the known values of independent variables in the model. This prediction is unbiased with relation to the log of the target variable. However, the exponential value of this prediction is biased with relation to the target variable. This paper addresses the measures to correct the bias in the prediction, which is introduced by exponentiation; the impacts on the variance of the ensuing predictions is also discussed. [ABSTRACT FROM AUTHOR]

The behaviour of a hydric system depends on three factors : (i) the state of the installation, (ii) the operating rules, and (iii) the inflows. While the first two factors are (in theory) known to the manager, the third can only be estimated by means of more or less precise forecasts. A significant part of the risk, to which is subjected the system at a given time, is induced by the uncertainty in the future inflows. The evaluation of this uncertainty is therefore a first step in the incorporation of risk into management. Its evaluation is then a stage preliminary to the integration of the risk in management. A method of construction of inflow scenarios starting from an arbitrary date t of the year is developed in this paper. It uses a Markovian process formerly developed by the authors to model short-term uncertainty in stream flow. These scenarios, which are not equiprobable, are built to reproduce the statistical behaviour of the river or reservoir and have the shape of an event tree whose structure is defined by the user before application of the method. Two examples of application on two rivers located in Quebec, Canada, are presented. [ABSTRACT FROM AUTHOR]

Because of uncertainty on inflows, a hydroelectric system may at any time leave its normal zone of operation and fail. This paper proposes a way to continuously measure this risk of failure by presenting it in the form of time-varying indicators. These indicators are very flexible and could be defined according to the manager's needs. They are calculated by stochastic simulation by using inflows scenarios built according to the observed conditions and the statistical behaviour of the river. The utility of this dynamic risk is highlighted by an application on the Cabonga reservoir located in Quebec, Canada. For this reservoir, we define and evaluate six hypothetical management rules. Four of these rules are explicitly related to the instant level of risk on this reservoir. Opposition between risk and system performance was highlighted in a quantitative way. [ABSTRACT FROM AUTHOR]

Fatigue of bituminous asphalts is one of the main types of pavement destruction. This phenomenon was studied extensively in Europe (RILEM) and in the United States (SHRP). There are no standardized tests in Quebec to assess asphalt fatigue resistance. In France, a new approach based on the determination of damage rates due to fatigue has been developed for a tension–compression test on asphalt core samples to study their fatigue strength. This paper presents a summary of the knowledge on asphalt fatigue. Damage rate analyses, developed by the DGCB (Département de Génie Civil et du Bâtiment) of the ENTPE at Lyon, is detailed and applied to stone matrix asphalt (SMA). Results show the validity of the approach by damage and the good fatigue damage strength of the SMA. [ABSTRACT FROM AUTHOR]

It is often necessary to estimate extreme events at sites where little or no hydrometric data are available. In such cases, one may use a regional estimation procedure, utilizing data available from other sites in the same hydrologic region. In general, a regional flood frequency procedure consists of two steps: determination of hydrologically homogeneous region and regional estimation. This paper presents the development of a regional flood frequency procedure based on canonical correlation analysis and multiple regression: (i) the canonical correlation analysis allows us to link a set of hydrological variables and a set of physiographical and (or) meteorological variables and, therefore, to determine the hydrological neighborhood of an ungauged site; (ii) the multiple regression allows us to transfer data from sites of the homogeneous region to the target site. The developed methodology was applied to the Saint-Maurice river region (Quebec, Canada). Using a jackknife procedure, several pairs of hydrological variables were compared to identify the most appropriate grouping. Key words: regionalization, frequency analysis, canonical correlation analysis, multiple regression.Il est fréquent d'avoir à estimer des événements extrêmes dans des sites où l'on dispose de peu ou même d'aucune information hydrologique. Lorsqu'une telle situation se produit, on peut avoir recours à une procédure d'es ti mation régionale qui utilise les données disponibles à d'autres sites appartenant à la même région hydrologique que le site d'intérêt. En général, une procédure d'estimation régionale est divisée en deux étapes : la détermination d'une région hydrologiquement homogène et l'estimation régionale. Cet article présente le développement d'une procédure d'es timation régionale qui combine l'analyse canonique des corrélations et la régression multiple : (i) l'analyse canonique des corrélations permet de mettre en relation un ensemble de variables hydrologiques et un ensemble de variables physiographiques et (ou) météorologiques et ainsi de déterminer le voisinage hydrologique d'un site non jaugé; (ii) la régression multiple permet le transfert des données des stations de la région homogène au site-cible. La méthodologie développée a été appliquée à la région de la rivière du Saint-Maurice (Québec, Canada). À l'aide d'une procédure « jackknife », plusieurs couples de variables hydrologiques ont été comparés afin de déterminer la combinaison conduisant aux résultats les plus intéressants. Mots clés : régionalisation, analyse fréquentielle, analyse canonique des corrélations, régression multiple. [ABSTRACT FROM AUTHOR]

In an attempt to apply the concepts developed by Carman and Klinkenberg for the measurement of permeability of a porous media using a gas, a permeameter for the in-situ measurement of intrinsic permeability of skin concrete has been developed. The established technique allows concentration of gas percolation through a well-defined zone in the superficial layer of concrete. The instrument, the measurement method, and the calculation procedure are described in details in this paper. Several series of tests have been performed in laboratory on concrete blocks (300 × 300 × 400 mm) to simulate measurements on the construction site. Three types of concrete, with different porosity, have been tested. The measurement of permeability performed on the concrete blocks have been accomplished both on shaped surfaces, which are representative of skin concrete, and on sawed surfaces, which are representative of mass concrete. Results show that the relationship between the water/cement ratio and the permeability of skin concrete varies distinctively compared with that of mass concrete. The permeameter allows quantification of what has been for a long time qualified as a determining element in terms of the durability of concrete against the corrosion of reinforcement, that is, the distinct permeability of skin concrete from that of mass concrete.Key words: skin concrete, in-situ permeability, intrinsic permeability, apparent permeability, permeameter, Klinkenberg.[Journal translation]Cherchant à appliquer les concepts développés par Carman et Klinkenberg pour la mesure de la perméabilité d'un milieu poreux à l'aide d'un gaz, un perméamètre pour mesurer in situ la perméabilité intrinsèque d'un béton de peau a été développé. La technique mise au point permet de concentrer la percolation du gaz à travers une zone bien définie dans la couche superficielle du béton. L'appareil, la méthode de mesure et le mode de calcul sont ici décrits en détail. Plusieurs séries d'essais ont été effectuées en laboratoire sur des blocs de béton (300 × 300 × 400 mm) de façon à simuler des mesures de chantier. Trois bétons de différentes porosités ont été testés. Des mesures de perméabilité effectuées sur les blocs de béton ont été faites autant sur les faces moulées, représentatives du béton de peau que sur des faces sciées, plus représentatives du béton de masse. Les résultats indiquent que la relation entre le rapport eau/ciment et la perméabilité du béton de peau varie distinctement de celle avec du béton de masse. Le perméamètre permet de quantifier ce qui est depuis longtemps qualifié d'élément déterminant au terme de la durabilité du béton contre la corrosion des armatures : la perméabilité distincte du béton de peau de celle de la masse.Mots clés : béton de peau, perméabilité in situ, perméabilité intrinsèque, perméabilité apparente, perméamètre, Klinkenberg. [ABSTRACT FROM AUTHOR]

The study presented in this paper is part of a project aiming at evaluating the potential use of aluminum in structures. The types of intervention could range from a simple repair or a reinforcement involving structural aluminum, the replacement of a used bridge deck by an aluminum deck, to the construction of a new bridge made in full or in part of aluminum. It is this latter type of intervention that justified a research project, the results of which are presented in this article. The first step involves identifying the most advantageous type of aluminum structural system from a structural standpoint as well as an economic standpoint. This step includes the analysis and partial design of 40 girder- or truss-type road bridges, spanning 15 and 35 m, supporting either an active concrete slab or an aluminum deck. These studies have shown that bridges built using a Pratt-type truss and an active concrete slab provided the best results. It is also shown that some calculation criteria, such as vibration, deflection, and fatigue criteria limited the extensive use of aluminum in bridges. In the second step, nine bridges are more comprehensively analysed and designed, based on the standards used in North America, and three are fully designed, including the connexions, in order to realize a cost analysis study that is as accurate as possible. Special attention is given to vibration and fatigue problems as well as to the details related to connexions calculation. The study concludes that the development of an aluminum-only medium span road bridge system is a non-viable project in the short to mid term from a structural standpoint as well as an economic standpoint, and it makes recommendations on the use of aluminum decks and on the continuation of the work.Key words: aluminum, analysis, bridges, connexions, design, fatigue, standards, vibration.[Journal translation]L'étude présentée dans cet article s'inscrit dans le cadre d'un projet visant à évaluer le potentiel d'utilisation de l'aluminium dans les ouvrages d'art. Le type d'intervention peut être une simple réparation ou un renforcement impliquant de l'aluminium structural, le remplacement d'un tablier de pont usagé par un tablier en aluminium ou, encore, la construction d'un nouveau pont entièrement ou en grande partie en aluminium. C'est ce dernier type d'intervention qui a justifié le projet de recherche dont les résultats font l'objet de cette présentation. Une première étape vise à identifier le type de système structural en aluminium le plus avantageux, tant du point de vue structural que du point de vue économique. Cette étape comprend l'analyse et le dimensionnement partiel de 40 ponts routiers de types poutres pleines ou à treillis, de 15 et 35 m de portée et supportant soit une dalle de béton participante, soit un tablier en aluminium. Ces travaux ont démontré que les ponts ayant des poutres triangulées de type Pratt et une dalle participante en béton armé présentent les meilleurs résultats. Il en ressort aussi que certains critères de calcul, tels les critères de vibration, de flèche et de fatigue limitent grandement l'utilisation de l'aluminium dans les ponts. Dans une deuxième étape, neuf ponts sont analysés et dimensionnés plus finement sur la base des normes en vigueur en Amérique du Nord et trois sont dimensionnés au complet, y compris les assemblages, dans le but de réaliser une étude comparative des coûts la plus précise possible. Une attention spéciale est portée aux problèmes de vibration et de fatigue ainsi qu'aux particularités du calcul des assemblages. L'étude conclut que le développement d'un système de pont routier entièrement en aluminium, de moyenne portée, est un projet non viable à court ou à moyen terme, tant du point de vue structural que du point de vue économique et fait des recommandations sur l'utilisation des tabliers en aluminium ainsi que sur la poursuite des travaux.Mots clés : aluminium, analyse, assemblages, dimensionnement, fatigue, normes, ponts, vibration. [ABSTRACT FROM AUTHOR]

In this paper a new thermoplastic damage model for plain concrete subjected to combined thermal and cyclic loading is developed using the concept of plastic-work hardening and stiffness degradation in continuum damage mechanics. Two damage variables are used: one for mechanical action and the other one for thermal action. Further, thermomechanical interaction strains have been introduced to describe the influence of mechanical loading on the physical process of thermal expansion of concrete. The constitutive relations for elastoplastic responses are decoupled from the degradation damage responses by using the effective stress concept. This method provides advantages in the numerical implementation. Efficient computational algorithms for the proposed model are subsequently explored and performance of this model is demonstrated with numerical examples.Key words: damage theory, plasticity, thermal, unilateral phenomenon, thermomechanical interaction.Dans ce papier un nouveau modèle thermo-plastique endommageable pour le béton soumis à des chargements mécaniques cycliques et thermiques combinés est développé. Ce modèle est basé sur la théorie de l'endommagement, deux variables y sont introduites, une première variable pour modéliser les effets du chargement mécanique et la seconde pour modéliser les effets du chargement thermique. L'influence du chargement mécanique sur le processus de déformation thermique est introduit en utilisant le concept de déformation d'interaction thermo-mécanique. Un critère multi-surface de plasticité est utilisé. Les relations constitutives de la réponse thermo-elasto-plastique sont découplées de celles de la réponse endommagée en utilisant le concept de la contrainte effective. Cette méthode confère une souplesse dans l'implémentation numérique. Une variable scalaire de dégradation est introduite pour simuler les effets d'endommagements thermo-mécaniques sur la rigidité et l'effet unilatéral lors de la fermeture de fissures. Ce modèle est mis en œuvre dans l'analyse du comportement de spécimens en béton d'une part, et de structures en béton armé soumis à des sollicitations thermo-mécaniques cycliques à hautes températures. Le résultat des simulations est comparé avec l'expérience.Mots clés : théorie de l'endommagement, plasticité, thermique, phénomène unilatéral, interaction thermo-mécanique. [ABSTRACT FROM AUTHOR]

This paper presents results of a numerical investigation on the nonlinear seismic behavior of a reinforced concrete system made of truncated coupled shear walls (CSWs) and a frame. The objective of the study is twofold: (a) examine the seismic behavior of CSW–frame systems with setbacks and (b) verify the adequacy of the National Building Code (NBC) as far as the design of such systems. The study considers two types of CSWs, coupled and partially coupled, two Canadian seismic zones, 4 and 6, six different levels of setbacks, and 10 historic seismic records encompassing a wide range of frequency content. Results of the study show that the CSW–frame system with no setback offers a satisfactory seismic behavior with regards to the sequence of plastification and the ductility demand. For the truncated systems, the NBC recommendations that the static method is not adequate is justified. Also, in the presence of setbacks, the columns show a higher degree of plastification with a possibility of formation of plastic mechanism (soft story). The ductility demand is also higher and can exceed the accepted practical limit in certain cases.Key words: coupled shear walls, frame, reinforced concrete, setback, seismic behavior, code.Cet article présente les résultats d'une investigation numérique sur le comportement sismique non linéaire d'un système en béton armé formé de murs de refend couplés (MRC) tronqués et d'un cadre. Les objectifs de l'étude sont d'une part d'examiner le comportement sismique d'un système MRC–cadre avec décrochement, et d'autre part de vérifier si les dispositions du Code national du bâtiment du Canada (CNB), quant à la conception de ce système, sont adéquates. L'étude considère deux types de MRC, couplés et partiellement couplés, deux zones sismiques canadiennes, 4 et 6, six niveaux de troncature différents et 10 accélérogrammes historiques couvrant un large éventail de contenus fréquentiels. Les résultats de l'étude montrent que la structure MRC–cadre non tronquée offre un comportement sismique satisfaisant compte tenu de la séquence de plastification et de la demande en ductilité maximum en deçà des limites pratiques, obtenues. Pour les structures tronquées, les recommandations du CNB selon lesquelles la méthode statique n'est pas adéquate, est justifiée. Par ailleurs, en présence de troncature, les poteaux montrent un plus haut taux de plastification avec possibilité de formation de mécanismes plastiques (« soft story »). La demande en ductilité est également plus élevée et peut excéder la limite pratique par endroit.Mots clés : murs de refend couplés, cadre, béton armé, décrochement, comportement sismique, code. [ABSTRACT FROM AUTHOR]

The seismic attenuation in concrete has seldom been studied, although it is an important parameter for survey design. In this paper, the seismic Q factor is estimated from data measured at the Carillon dam. Three methods were used for this study: amplitude decay yielding a value of 5.1 ± 1.6, spectral ratio giving a value of 8.3 ± 3.5, and a value of 7.5 ± 14.9 was obtained from the rise-time technique. These values are weak compared with what is generally observed in rocks, and slightly lower than values obtained on laboratory concrete samples. However, the average P wave velocity measured on the investigated area is 4081 ± 95 m·s[sup –1] , an indication of the good quality of the material. Consequently, this strong attenuation could be attributed on one hand to energy loss, and on the other hand to scattering caused by the intrinsic cement–aggregate composition of concrete. It is also possible that an inadequate sensor coupling had the effect of reducing the observed Q value. Key words: seismic attenuation, concrete dams, microseismic monitoring, coupling.Paramètre important pour la planification de levés sismiques, l'atténuation sismique a été peu étudiée dans les bétons. Dans cet article, le facteur de qualité sismique Q est évalué au barrage de Carillon selon les méthodes du rapport des amplitudes, du rapport des spectres d'amplitude et du temps de montée. Les mesures obtenues sont respectivement de 5,1 ± 1,6, de 8,3 ± 3,5 et de 7,5 ± 14,9. Ces valeurs sont faibles en regard de ce qui est généralement observé dans les roches, et légèrement plus faibles que des valeurs mesurées sur des bétons en laboratoire. Par ailleurs, le béton de la partie du barrage auscultée présente une vitesse d'onde P moyenne de 4081 ± 95 m·s[sup –1] , indiquant une bonne qualité du matériau. En conséquence, la forte atténuation pourrait être attribuable d'une part à la perte de l'énergie sismique sous forme de friction, et d'autre part à une atténuation de diffusion occasionnée par la composition ciment-granulat intrinsèque du béton. Il est également possible qu'un couplage inadéquat des capteurs ait pour effet de réduire la valeur observée de Q. Mots clés : atténuation sismique, barrages en béton, auscultation microsismique, couplage. [ABSTRACT FROM AUTHOR]

This paper proposes a methodology for the regional analysis of drought flows. This approach lies on the combination of two procedures. (i) The simple scale invariance method for regional series of drought flows, based on the analysis of the relation moments-surfaces or the relation quantiles-surfaces, explains the spatial variability of drought processes by their indexation on a series of scale parameters, essentially the size of the drainage basin. This procedure principally aims at delimitating homogeneous regions, and this characterizes the first condition of a regional estimation. (ii) Frequency analysis of minimum flows, with the approach using tail conditional models, consists in adjusting a probability distribution to values that are smaller than or equal to some given threshold. As a fact, this procedure gives some more weight to the lower part of the distribution by defining a priori a level of censure, mainly a threshold u[sub i] called ceiling value. This procedure establishes the second condition of a regional estimation, that is, the determination of a regional estimation model. This methodology has been applied to analyze drought flow characteristics of 187 hydrometric stations scattered in the province of Quebec. Results have shown that the first to the sixth order non-central moments follow a simple scale invariance with respect to the area of the watershed. As a result, analysis of the residuals of these six moments has allowed classifying hydrologically similar watersheds. On the basis of the results from the analysis on the residuals of the sixth moment, the province has been divided into two homogeneous regions. The behaviour of the minimum flows from these different regions has shown that they, too, followed a simple scale invariance.Key words: regionalization, flow, drought, scale invariance, tail model, non-central moment.[Journal translation]L'article propose une méthodologie d'analyse régionale des débits d'étiage; cette approche repose sur la combinaison de deux procédures. (i) La méthode d'invariance d'échelle simple des séries régionales de débits d'étiage, basée sur l'analyse de la relation moments–surfaces ou de la relation quantiles–surfaces; en d'autres termes cette méthode explique la variabilité spatiale des processus d'étiage par leur indexation sur une série de paramètres d'échelle, essentiellement la taille des bassins de drainage. Cette procédure a comme rôle principal, la délimitation des régions homogènes, qui caractérise la première condition d'une estimation régionale. (ii) L'analyse de fréquence des débits minimums avec l'approche par modèles de queue conditionnels, qui consiste à ajuster une distribution de probabilité aux données qui sont inférieures ou égales à un certain seuil de censure. En fait, cette procédure accorde plus de poids à la partie inférieure de la distribution en définissant a priori un niveau de censure des données principalement un seuil u[sub i] , appelé niveau plafond « ceiling value ». Cette méthode vérifie la deuxième condition d'estimation régionale, à savoir la détermination du modèle d'estimation régional. Cette méthodologie a été appliquée à l'analyse des caractéristiques des débits d'étiage de 187 stations hydrométriques réparties dans la province de Québec. Les résultats ont montré que les moments non centraux d'ordre un à six suivent une invariance d'échelle simple par rapport à la superficie du bassin versant. Suite à ce résultat, une analyse des résidus des six moments a permis de déterminer les bassins hydrologiquements semblables. Sur la base du résultat de l'analyse des résidus du sixième moment nous avons scindé la province en deux régions homogènes. Le comportement des débits minimums des différentes régions a montré qu'eux aussi suivaient une invariance d'échelle simple.Mots clés : régionalisation, débit, étiage, invariance d'échelle, modèle de queues, moment non central. [ABSTRACT FROM AUTHOR]