References of "Degée, Hervé"
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See detailEffects of the presence of free lime nodules into concrete: experimentation and modelling
Courard, Luc ULg; Degée, Hervé ULg; Darimont, Anne ULg

in Cement and Concrete Research (2014), 64

When nodules of lime are embedded into concrete, the expansion accompanying the transformation of CaO into Ca(OH)2 induces stresses and strains in both the lime nodule and in the concrete matrix. The ... [more ▼]

When nodules of lime are embedded into concrete, the expansion accompanying the transformation of CaO into Ca(OH)2 induces stresses and strains in both the lime nodule and in the concrete matrix. The concrete cover thickness, the diameter and the shape of the lime nodule as well as the mechanical characteristics of concrete and lime are the key parameters influencing the development of internal pressure and hence controlling the risk of cracking or pop-out. In order to study the effect of lime into cementitious concretes, laboratory investigations and modelling have been performed and show that the minimum cover thickness necessary to avoid the development of the pop-out phenomenon is estimated of the order of half the diameter of the inclusion. This is coming from the observation that expansion happens inside the porosity of the hydrated lime Ca(OH)2: ESEM and DRX analysis confirm the effect of confinement in the development of crystals. [less ▲]

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See detailHARBIYE AQUEDUCT: A RECORD OF PAST EARTHQUAKES
Lamair, Laura ULg; Degée, Hervé ULg; Hubert, Aurelia ULg et al

Poster (2014, August)

This paper presents a detailed analysis of Harbiye aqueduct (Hatay, Turkey). The region is situated at the junction of two major faults (East Anatolian fault and the Dead Sea fault) and is well known for ... [more ▼]

This paper presents a detailed analysis of Harbiye aqueduct (Hatay, Turkey). The region is situated at the junction of two major faults (East Anatolian fault and the Dead Sea fault) and is well known for his important historic seismicity. The aqueduct is located close to Antioch on the Orontes (known as Antakya). The city was founded in the third century BC. Harbiye aqueduct is characterized by different stages of building (Benjelloun et al., submitted). A phase is dated to Caligula period. After the 37 AD earthquake, the aqueduct was rebuilt. We noticed the presence of two dissociated travertine and a changing of masonry material. We also observed several damages and repair structures dating from Roman time. We assume that our observations are the results of one or more earthquakes. Since the construction of the aqueduct, historical seismic records mention 13 earthquakes that provoked severe damages in the city of Antioch (Guidoboni et al. 1994, Al-Tarazi, 1999, Över et al. 2002). The last one occurred in 1872 (M=7.2). In order to test our hypothesis, we modelled the structure of the aqueduct by using FineLg, a software developed at University of Liege. The seismic signals were chosen in the European Strong-motion database (Ambraseys et al., 2002) according the following criteria: a bedrock station (to avoid site effect), a strike-slip fault mechanism and a distance between the station and the epicenter around 20-30 km. The aqueduct is located at about 25 km of the Dead Sea Fault. We tested several magnitudes for the purpose of estimate the magnitude of the earthquake(s) which destroy(s) the studied aqueduct. Our results highlight the bond between the magnitude, the damage and the weakness area of this type of structure. [less ▲]

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See detailSIMPLIFIED SEISMIC ANALYSIS OF LOCK GATES
Buldgen, Loïc ULg; Degée, Hervé ULg; Lesourne, Hervé et al

in PIANC 2014 Conference (2014, June 02)

The paper deals with the seismic design of lock gates. When such structures are submitted to an earthquake, the water contained in the chamber is responsible for an additional hydrodynamic pressure acting ... [more ▼]

The paper deals with the seismic design of lock gates. When such structures are submitted to an earthquake, the water contained in the chamber is responsible for an additional hydrodynamic pressure acting on the gate. This one is the sum of three different parts, respectively called the convective, rigid and flexible contributions. The two first ones have already been extensively studied in the literature, but the flexible part is more difficult to assess as it is largely influenced by the coupling occurring between the fluid and the gate. To overcome this difficulty, it is of course possible to use finite elements software, but doing so is not always convenient. This is why some research have been undertaken to provide a rapid way for approximating the flexible pressure on lock gates. This is achieved by applying the analytical approach that is shortly presented in this paper. As a matter of validation, the results obtained through this simplified procedure are compared to numerical solutions. The agreement between both of them is found to be satisfactory. [less ▲]

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See detailSeismic behavior of Thin-Bed Layered Unreinforced Clay Masonry Shear Walls Including Soundproofing Elements
Mordant, Christophe ULg; Dietz, Matt; Taylor, Colin et al

in Ilki, Alper; Fardis, Michael (Eds.) Seismic Evaluation and Rehabilitation of Structures, Geotechnical, Geological and Earthquake Engineering 26 (2014)

According to the current standards, unreinforced masonry may only be used in regions of low seismicity as the material for the lateral-load resisting system. This requirement may be too safe-sided and ... [more ▼]

According to the current standards, unreinforced masonry may only be used in regions of low seismicity as the material for the lateral-load resisting system. This requirement may be too safe-sided and leading to not cost-effective solutions for moderately seismic regions. This chapter presents overview of experimental results from shake table tests on unreinforced masonry shear walls carried out in the EQUALS Laboratory of Bristol University, in order to assess, and possibly enhance, the current seismic design rules. The study also includes as additional parameter the presence of soundproofing devices required in buildings with numerous dwellings, in order to achieve the acoustic isolation recommended by recent standards. In practice the required level of acoustic isolation is obtained by locating horizontal rubber layers in the wall. These layers are likely to influence significantly the dynamic response of the wall and hence of the whole structure under seismic actions. Tests are performed on walls realized with masonry units and construction methods typical of North-Western Europe. [less ▲]

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See detailNumerical simulation of the Roll forming of thin-walled sections and evaluation of corner strength enhancement
Rossi, Barbara ULg; Degée, Hervé ULg; Boman, Romain ULg

in Finite Elements in Analysis & Design (2013), 72

Cold roll forming modifies the mechanical properties of thin-walled profiles by strain hardening. The understanding of this phenomenon, which is rather good for profiles made of traditional construction ... [more ▼]

Cold roll forming modifies the mechanical properties of thin-walled profiles by strain hardening. The understanding of this phenomenon, which is rather good for profiles made of traditional construction steel, is mandatory for assessing the member resistance. Less information is however available for profiles made of materials exhibiting a pronounced degree of nonlinearity of the stress-strain curve such as high-strength and stainless steels. Current codes generally encounter difficulties for modelling this fabrication process because of the size of industrial mills. Indeed, accurate modelling of the continuous cold roll forming process using finite elements requires a huge number of elements leading to excessive CPU times. Therefore, modellers usually reduce the geometry of the formed sheet or increase the size of the finite elements, inducing a loss of accuracy in the results. In this work, the finite element software METAFOR is used to model cold roll forming of channel profiles made of high-strength and stainless steels. The numerical results, expressed in terms of corner strength enhancement versus radius–to–thickness ratio, are compared against an existing predictive model. [less ▲]

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See detailExperimental tests on the seismic behaviour of unreinforced load-bearing masonry structures
Mordant, Christophe ULg; Dietz, Matt; Degée, Hervé ULg

in Heuer, Rudolf; Adam, Christoph (Eds.) Proceedings of Vienna Congress on recent advances in earthquake engineering and structural dynamics (VEESD 2013) (2013, August)

The paper describes recent experimental shaking table tests carried out on load-bearing unreinforced masonry shear walls in earthquake conditions, within the European research project SERIES. The first ... [more ▼]

The paper describes recent experimental shaking table tests carried out on load-bearing unreinforced masonry shear walls in earthquake conditions, within the European research project SERIES. The first phase of the experimental activity investigates the response of four simple unreinforced masonry walls, two of them including rubber acoustic isolation devices. The second phase deals with the testing of specimens with T- and Lshaped walls (shear wall with flanges) coupled at their top by a concrete lintel and a prefabricated concrete slab. The paper summarizes interesting results obtained on the general behaviour of the walls, on the estimation of equivalent elastic and shear moduli, on the influence of the soundproofing devices and on the global frame behaviour of the system. [less ▲]

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See detailShaking table tests on unreinforced load-bearing masonry walls - Comparison with simple rocking models
Mordant, Christophe ULg; Dietz, Matt; Degée, Hervé ULg

in ECCOMAS Thematic Conference - COMPDYN 2013: 4th International Conference on Computational Methods in Structural Dynamics and Earthquake Engineering, Proceedings - An IACM Special Interest Conference (2013, June)

Assessment of the overall seismic performances of multi-storey unreinforced masonry structures requires an appropriate characterization of the behaviour of their structural components, in particular when ... [more ▼]

Assessment of the overall seismic performances of multi-storey unreinforced masonry structures requires an appropriate characterization of the behaviour of their structural components, in particular when these are subjected to a dynamic ground motion input. In order to develop a better understanding on this issue and in a further perspective of investigating the consequences of the presence of 1 cm thick rubber elements used for improving the sound-proofing performances of the building, shaking table tests have been carried out in the framework of the European project SERIES. Four single walls were tested. These were built with high resistance thin-bed layered clay masonry with empty vertical joints. Two of them had an aspect ratio close to 1, while the other two were close to 0.4. One wall of each aspect ratio included rubber devices at its bottom and top to enable comparisons and conclusions about the influence of rubber on the wall behaviour. The test results were then partially compared to results obtained with a theoretical rocking model considering the wall as a rigid body. The results summarized in the present contribution evidence a significant rocking behaviour for the highest input acceleration levels. Characterization of this behaviour is however strongly dependent on the aspect ratio of the wall and on the presence or not of rubber devices in terms of natural frequencies, damping, dynamic amplifications and progressive damage with increasing acceleration levels. It is also showed that the theoretical rocking predictions are in good agreement with the experimental results for high acceleration levels, while the behaviour is closer to the one of a cantilever for the lower levels. It is finally evidenced that, in presence of acoustic rubber devices, amplitudes of the rocking motion are increased but with a more limited damaging of the wall because of the capacity of the rubber to absorb the impact energy. Results of this study on single walls are expected to be further extended to global masonry structures, account taken for the influence of actual boundary conditions of the wall. [less ▲]

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See detailEffects of the roll forming process on the mechanical properties of thin-walled sections made of non linear metallic materials
Rossi, Barbara ULg; Boman, Romain ULg; Degée, Hervé ULg

in Proceedings of the 6th International Conference on Thin Walled Structures: ICTWS2011, Timisoara 5-7 September 2011 (2011, September 05)

It is well known that the cold-forming process is likely to significantly enhance the mechanical properties of the profile by strain hardening leading to increased resistance compared to a resistance ... [more ▼]

It is well known that the cold-forming process is likely to significantly enhance the mechanical properties of the profile by strain hardening leading to increased resistance compared to a resistance assessment based on nominal properties. It is thus necessary to accurately determine the mechanical properties after the cold process of fabrication. The knowledge on these enhanced properties is rather good for profiles made of traditional construction steel (carbon steel with yield strength between 200 and 400 MPa) characterized by an elasticplastic behaviour. However less information is available for profiles made of materials exhibiting a non linear stress-strain relationship. In this context, the paper presents a parametric study on roll-profiled channel sections. For that purpose, the finite element code METAFOR developed at the LTAS division of the University of Liège is used to simulate the forming process of profiles made of high strength steel and of stainless steel. In the simulations, different values of the radius to thickness ratio of the corners are considered. The results of the numerical simulations are expressed in terms of resulting proof strength in the corners versus the radius to thickness ratio for the different materials. They are finally compared to existing predictive formulations. Additional considerations are also given on the forming process itself (i.e. on the configuration of the rolls or on the springback). [less ▲]

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See detailConception parasismique dans le contexte de l’Eurocode 8
Plumier, André ULg; Degée, Hervé ULg

Learning material (2011)

Le texte qui suit rassemble des éléments nécessaires à la maîtrise du projet de construction en zone sismique : conception d'ensemble des structures, définition des données nécessaires au calcul, choix de ... [more ▼]

Le texte qui suit rassemble des éléments nécessaires à la maîtrise du projet de construction en zone sismique : conception d'ensemble des structures, définition des données nécessaires au calcul, choix de la méthode de calcul, vérifications des éléments structurels. Il contient aussi un rappel synthétique de dynamique des structures, mais ce sujet, comme d’autres, requiert la lecture d’autres ouvrages. Pour cette raison on s’est efforcé de donner aussi les références d’ouvrages de la littérature et de sites Internet qui tous apportent des informations utiles. Des mises à jour sont prévues. L’édition 2011 est la 5e version du cours de conception parasismique de l’Université de Liège. C’est une évolution de la version de 1992, consécutive à la parution en 2004 de l’Eurocode 8, Norme Parasismique Européenne, dans sa première version Euronorme ou « EN » (« EN1998-1 : 2004 »). Il est opportun qu’un cours de conception parasismique soit en phase avec les concepts et notations du document qui est un code accepté comme référence des projets dans toute l’Europe en 2011. L’édition 2011 s’appuie sur le développement des connaissances acquises au sein du Groupe Sismique de l’Université de Liège par son travail dans 15 projets de recherche européens et belges, sa contribution à des projets de construction et une participation intense au développement des règlements parasismiques Européens et nationaux : CECM, Eurocode 8, Annexes Nationales, Guide pour maisons individuelles. [less ▲]

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See detailGeometrically non linear analysis of steel Storage racks submitted to earthquake loading
Degée, Hervé ULg; Rossi, Barbara ULg; Jehin, Denis

in International Journal of Structural Stability & Dynamics (2011), 11(5), 949-967

Steel storage racks are light and flexible structures. When submitted to earthquake loading, they can exhibit very large transverse displacements and are thus prone to significant consequences of second ... [more ▼]

Steel storage racks are light and flexible structures. When submitted to earthquake loading, they can exhibit very large transverse displacements and are thus prone to significant consequences of second-order geometrical effects. In the context of the drafting of European recommendations for the design of steel pallet racks for their seismic resistance, this paper presents a parameter study comparing the various methods commonly used in practice for analyzing the seismic structural behavior of racks (i.e. "modal response spectrum analysis" and "lateral force method analysis") as well as the different ways to account for geometrically nonlinear effects in these conventional methods of analysis in the case of structures designed for low ductility. [less ▲]

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See detailSEISMICALLY RETROFITTING AND UPGRADING RC-MRF BY USING EXPANDED METAL PANELS
Phung Ngoc, Dung ULg; Degée, Hervé ULg; Plumier, André ULg

Scientific conference (2011, January 15)

Expanded Metal is a second product made from metal sheet by first cuttings, cold-drawing, and finally by being flattened. A research is under way at University of Liege with the aims at determining the ... [more ▼]

Expanded Metal is a second product made from metal sheet by first cuttings, cold-drawing, and finally by being flattened. A research is under way at University of Liege with the aims at determining the mechanical properties of this type of material under seismic excitations. In view of their application to building seismic retrofitting and upgrading, three approaches: analytical models, numerical simulations and experimental investigations, have been used to characterize the mechanic behavior of expanded metal sheets which are monotonically and cyclically loaded in shear. Nonlinear numerical simulations and experimental tests are used to determine the hysteretic behavior of expanded metal shear panels (EMSP), and an analytical model is then proposed, with the aims of using that to study the influence of such EMSP when they are used to retrofit and upgrade reinforced concrete moment resisting frames (RC-MRF). Many RC-MRF are then designed in two cases: (1) in accordance with only Eurocode 2 and (2) in accordance with both Eurocode 2 and Eurocode 8. Capacities of such designed structures are evaluated by using nonlinear static analysis (Pushover) and nonlinear time history analysis under different types of soils and ground motions. The efficiency of using EMSP is evaluated in terms of strength, stiffness and energy dissipation. Additionally, with the presence of EMSP, some unfavorable behavior of RC-MRF under seismic action such as soft story mechanism can be prevented. [less ▲]

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See detailEclatement du béton dû à granulats contaminés à la chaux vive
Courard, Luc ULg; Darimont, Anne ULg; Degée, Hervé ULg

Article for general public (2011)

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See detailBehaviour of EMP under shear loadings
Phung Ngoc, Dung ULg; Degée, Hervé ULg; Plumier, André ULg

in Behaviour of EMP under shear loadings- SDSS 2010 (2010)

Experimental and theoretical study of expanded metal panels (EMP) has shown that they are useful for seismically retrofitting reinforced concrete moment resisting frames (RC-MRF). Although this product ... [more ▼]

Experimental and theoretical study of expanded metal panels (EMP) has shown that they are useful for seismically retrofitting reinforced concrete moment resisting frames (RC-MRF). Although this product has merit of strength and ductility, it is at present only used for non-structural applications. There is no guidance existing to help the engineers determine the mechanical properties or to indicate in which field of the structures this product can be used. With the aims at providing quantitative data for these purposes and at introducing a simplified model of EMP working in shear, description and comparison of the results of 22 monotonic and cyclic experiments of 4 profiles of EMP in small and large scale is presented. Numerical approach with FINELG, a nonlinear finite element code developed at University of Liege, is used to calibrate and simulate the tests. A good correlation between tests and numerical simulations is observed. [less ▲]

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See detailSeismic retrofitting and upgrading reinforced concrete moment resisting frames by using expanded metal shear panels
Phung Ngoc, Dung ULg; Degée, Hervé ULg; Plumier, André ULg

in Seismic retrofitting and upgrading reinforced concrete moment resisting frames by using expanded metal shear panels (2010)

Expanded Metal is a second product made from metal sheet by first cuttings, cold-drawing, and finally by being flattened. A research is under way at University of Liege with the aims at determining the ... [more ▼]

Expanded Metal is a second product made from metal sheet by first cuttings, cold-drawing, and finally by being flattened. A research is under way at University of Liege with the aims at determining the mechanical properties of this type of material under seismic excitations. In view of their application to building seismic retrofitting and upgrading, three approaches: analytical models, numerical simulations and experimental investigations, have been used to characterize the mechanic behavior of expanded metal sheets which are monotonically and cyclically loaded in shear. Nonlinear numerical simulations and experimental tests are used to determine the hysteretic behavior of expanded metal shear panels (EMSP), and an analytical model is then proposed, with the aims of using that to study the influence of such EMSP when they are used to retrofit and upgrade reinforced concrete moment resisting frames (RC-MRF). Many RC-MRF are then designed in two cases: (1) in accordance with only Eurocode 2 and (2) in accordance with both Eurocode 2 and Eurocode 8. Capacities of such designed structures are evaluated by using nonlinear static analysis (Pushover) and nonlinear time history analysis under different types of soils and ground motions. The efficiency of using EMSP is evaluated in terms of strength, stiffness and energy dissipation. Additionally, with the presence of EMSP, some unfavorable behavior of RC-MRF under seismic action such as soft story mechanism can be prevented. [less ▲]

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See detailEtude expérimentale de la résistance de panneaux de metal déployé soumis à des solicitations cycliques de cisaillement.
Phung Ngoc, Dung ULg; Degée, Hervé ULg; Plumier, André ULg

in Experimental Study of the Resistance of Expanded Metal Panels Submitted to Cyclic Shear Tests (2010)

Experimental and theoretical study of expanded metal panels (EMP) has shown that they are useful for seismically retrofitting reinforced concrete moment resisting frames (RC-MRF). Although this product ... [more ▼]

Experimental and theoretical study of expanded metal panels (EMP) has shown that they are useful for seismically retrofitting reinforced concrete moment resisting frames (RC-MRF). Although this product has merit of strength and ductility, it is at present only used for non-structural applications. There is no guidance existing to help the engineers determine the mechanical properties or to indicate in which field of the structures this product can be used. With the aims at providing quantitative data for these purposes and at introducing a simplified model of EMP working in shear, description and comparison of the results of 22 monotonic and cyclic experiments of 4 profiles of EMP in small and large scale is presented. Numerical approach with FINELG, a nonlinear finite element code developed at University of Liege, is used to calibrate and simulate the tests. A good correlation between tests and numerical simulations is observed. [less ▲]

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See detailContributions to the knowledge about the seismic behaviour of typical Belgian masonry houses
Degée, Hervé ULg; Plumier, André ULg

in Proceedings of the 8th International Masonry Conference (2010)

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See detailEvaluatie van de gevolgen van de aanwezigheid van kalknodules in beton - Besluiten
Courard, Luc ULg; Darimont, Anne ULg; Degée, Hervé ULg

Report (2010)

De oorspronkelijke verontreiniging (0.7% van het gewicht aan granulaten) is met factor 100 verminderd tijdens de productie van de granulaten en het verwerken van het beton. De maximale verontreiniging ... [more ▼]

De oorspronkelijke verontreiniging (0.7% van het gewicht aan granulaten) is met factor 100 verminderd tijdens de productie van de granulaten en het verwerken van het beton. De maximale verontreiniging geobserveerd op de werf is 0.006% van het gewicht aan granulaten. Op de werf zijn de pop-outs weinig talrijk, de kalknodules zijn klein en de pop-outs ondiep. Geen enkele scheurvorming trof het beton. Het besluit van deze studie, op basis van een worstcasescenario en met een aan zekerheid grenzende waarschijnlijkheid, is dat de verontreiniging geen risico inhoudt wat betreft duurzaamheid en stabiliteit van de werken. We bedoelen daarmee dat het risico op verlies van sterkte en het risico voor stabiliteit en duurzaamheid van structurele elementen (platen, wanden, balken) verbonden aan de aanwezigheid van nodules zo miniem zijn dat ze in feite kleiner zijn dan de risico’s ten gevolge van de normaal aanvaardbare variabiliteit van de eigenschappen van beton, in overeenstemming met de omstandigheden op de werf. Na hydratatie oefenen de verdichte portlandiet-nodules geen druk meer uit en gedragen ze zich als gewone granulaten. De risico’s verbonden aan de betonverontreiniging door kalknodules zijn dus uitsluitend esthetisch van aard en betreffen een maximale diepte van 2 tot 4 cm. [less ▲]

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See detailEvaluatie van de gevolgen van de aanwezigheid van kalknodules in beton - Gedetailleerd verslag
Courard, Luc ULg; Darimont, Anne ULg; Degée, Hervé ULg

Report (2010)

De oorspronkelijke verontreiniging (0.7% van het gewicht aan granulaten) is met factor 100 verminderd tijdens de productie van de granulaten en het verwerken van het beton. De maximale verontreiniging ... [more ▼]

De oorspronkelijke verontreiniging (0.7% van het gewicht aan granulaten) is met factor 100 verminderd tijdens de productie van de granulaten en het verwerken van het beton. De maximale verontreiniging geobserveerd op de werf is 0.006% van het gewicht aan granulaten. Op de werf zijn de pop-outs weinig talrijk, de kalknodules zijn klein en de pop-outs ondiep. Geen enkele scheurvorming trof het beton. Het besluit van deze studie, op basis van een worstcasescenario en met een aan zekerheid grenzende waarschijnlijkheid, is dat de verontreiniging geen risico inhoudt wat betreft duurzaamheid en stabiliteit van de werken. We bedoelen daarmee dat het risico op verlies van sterkte en het risico voor stabiliteit en duurzaamheid van structurele elementen (platen, wanden, balken) verbonden aan de aanwezigheid van nodules zo miniem zijn dat ze in feite kleiner zijn dan de risico’s ten gevolge van de normaal aanvaardbare variabiliteit van de eigenschappen van beton, in overeenstemming met de omstandigheden op de werf. Na hydratatie oefenen de verdichte portlandiet-nodules geen druk meer uit en gedragen ze zich als gewone granulaten. De risico’s verbonden aan de betonverontreiniging door kalknodules zijn dus uitsluitend esthetisch van aard en betreffen een maximale diepte van 2 tot 4 cm. [less ▲]

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See detailEvaluation de l'effet de la présence de nodules de chaux dans les bétons - Conclusions
Courard, Luc ULg; Darimont, Anne ULg; Degée, Hervé ULg

Report (2010)

La contamination d’origine (0.7% du poids des granulats) a été amortie d’un facteur 100 durant les étapes de fabrication des granulats et de mise en œuvre des bétons. La pollution maximale observée sur ... [more ▼]

La contamination d’origine (0.7% du poids des granulats) a été amortie d’un facteur 100 durant les étapes de fabrication des granulats et de mise en œuvre des bétons. La pollution maximale observée sur chantier est de 0.006 % du poids des granulats. Sur chantier, les pop-out sont peu nombreux, les nodules de chaux sont de petite taille et les éclats de faible profondeur. Aucune fissuration n’affecte le béton. Cette étude conclut, sur la base du scénario du pire et avec une probabilité avoisinant la certitude, que la contamination ne présente pas de risque en termes de durabilité et de stabilité des ouvrages. Nous entendons par-là, que le risque de perte de résistance et le risque sur la stabilité et la durabilité des éléments de structure (dalles, voiles, poutres) liés à la présence des nodules sont tellement minimes qu’ils sont en réalité nettement plus faibles que ceux qui résultent de la variabilité normale tolérée pour les propriétés des bétons, en rapport avec les conditions de chantier. Après hydratation, les nodules densifiés de portlandite n’exercent plus de pression et se comportent comme de simples granulats. Les risques liés à la contamination des bétons par les nodules de chaux sont donc exclusivement de nature esthétique et concernent une profondeur maximale de 2 à 4 cm. [less ▲]

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