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See detailDécouverte d'un nouveau syndrome : X-LAG (pour X-Linked Acrogigantism)
Beckers, Albert ULg

Scientific conference (2015, June 19)

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See detailModelling of the response of a slender structure to vortex shedding in the atmospheric boundary layer
Wertz, Freddy ULg

Master's dissertation (2015)

This work is about modelling vortex induced vibrations on a 100 m height generic reinforced concrete pylon with a square cross-section and a 20 height/width ratio, vibrating in its first across-wind ... [more ▼]

This work is about modelling vortex induced vibrations on a 100 m height generic reinforced concrete pylon with a square cross-section and a 20 height/width ratio, vibrating in its first across-wind bending mode at a frequency of 0.35 Hz for a critical wind speed of 14.6 m/s. An equivalent aeroelastic model made of a copper spline modelling the dynamic behaviour and a foam blocks skin modelling the external geometry and adjusting the mass is realized. Similitude laws are discussed based on their relevance in the simulation. The model is validated through experimental modal analysis and is tested in wind tunnel uniform and boundary layer winds. 3 turbulence levels and 4 incidence angles are tested. Measured amplitudes are small (around 5 cm in full scale). The influence of turbulence is qualitatively visible in experimental results. Analytical and numerical estimation procedures are also implemented and discussed: The Eurocode norm, a harmonic load model and the spectral model of Vickery and Clark. The Eurocode approach gives the most conservative estimations and is followed by estimations from the harmonic load model having the correlation length as parameter. The spectral model gives estimations of the order of magnitude of experimental measurements in the wind tunnel for a spectral bandwidth of 0.2 and a correlation length comprised between 1 and 3 times the width of the cross-section. [less ▲]

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See detailLe règlement de la procédure en cas de dessaisissement du juge d’instruction incompétent ratione loci ?
Michiels, Olivier ULg

in Revue de Jurisprudence de Liège, Mons et Bruxelles (2015), (127), 1174-1178

Lorsque la chambre du conseil ordonne le dessaisissement du juge d’instruction pour incompétence territoriale, le procureur du Roi, auquel le dossier est renvoyé ne peut se dispenser de saisir le juge ... [more ▼]

Lorsque la chambre du conseil ordonne le dessaisissement du juge d’instruction pour incompétence territoriale, le procureur du Roi, auquel le dossier est renvoyé ne peut se dispenser de saisir le juge d’instruction territorialement compétent et faire l’économie du règlement de la procédure devant les juridictions d’instruction [less ▲]

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See detailResiliency of a Community of Buildings to Fire Following Earthquake
Gernay, Thomas ULg; Elhami Khorasani, Negar; Garlock, Maria

Conference (2015, June 19)

Cascading multi-hazard events, such as fires following an earthquake, can trigger progressive collapse of structures. In cascading earthquake and fire events, buildings that may have already experienced ... [more ▼]

Cascading multi-hazard events, such as fires following an earthquake, can trigger progressive collapse of structures. In cascading earthquake and fire events, buildings that may have already experienced damage due to a primary earthquake hazard, should cope with a secondary extreme event. This work provides a methodology to evaluate the risk of fire ignitions after an earthquake and building responses in a community. The work has two components: In the first part, a model is developed for predicting the probability of ignition in a building due to an earthquake. This probabilistic model relies on the data from seven significant earthquakes that took place in the U.S. between 1983 and 2014. The main parameters influencing the probability of ignition are found to be the peak ground acceleration, the type of building material, and the main features of the environment in which the buildings are located (i.e. the total square footage and the population density). In the second part of this work, fragility curves are developed for performance of structures under fire, to quantify the probability of exceeding a damage state given a fire scenario. The probabilistic ignition model is implemented in Ergo/Maeviz, a GIS based risk assessment software platform developed at the Mid-America Earthquake Center at UIUC. Ergo/Maeviz provides the probability of ignition after an earthquake for each building in a region of study, and the overall risk for the community. The developed package in Ergo/Maeviz is validated against number of historical fire following earthquake events. For the future work, the developed fragility curves for buildings under fire will be implemented in Ergo/Maeviz to integrate the probability of ignition and possible damage states of the buildings. This research integrates multi-hazard analysis and risk management to plan mitigation and recovery strategies, and to obtain resilient communities. [less ▲]

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See detailModel polyQ proteins based on the beta-lactamase BlaP: How non-polyQ regions influence the polyQ length-dependent aggregation process
Huynen, Céline ULg

Doctoral thesis (2015)

Neurodegenerative amyloid diseases are fatal disorders representing an important human health and economic burden. Amongst them, nine disorders are classified as polyglutamine (polyQ) diseases, for which ... [more ▼]

Neurodegenerative amyloid diseases are fatal disorders representing an important human health and economic burden. Amongst them, nine disorders are classified as polyglutamine (polyQ) diseases, for which no treatment is yet available. They are all characterized by the pathological expansion of a poly(CAG) sequence, above a specific threshold, within the coding sequence of nine unrelated genes, translated in nine polyQ proteins. The polyQ expansion, the only common point, is the critical determinant for polyQ disease development by triggering protein aggregation into amyloid fibrils. More recent studies however indicate that the protein context modulates the polyQ-induced aggregation process and the disease phenotype. The objectives of my thesis are to deeper investigate the molecular determinants of the complex interplay between the propensity of the polyQ tract to trigger protein aggregation and the modulating role of non-polyQ regions in order to allow the identification of strategies to interfere with the pathological aggregation process. For that purpose, model polyQ proteins, referred to as BlaP-polyQ chimeras, based on the β-lactamase BlaP and polyQ sequences (23 – 79Q) inserted at two positions (197, in between or not unstructured peptides, or 216), are used and their aggregation properties are characterized under several conditions. We first observe that the polyQ length is determinant for BlaP-polyQ chimera aggregation. Indeed, there is a Q-threshold for the aggregation into amyloid fibrils and for fibril elongation. Above this threshold, the aggregation in solution and the elongation rate increase with the length of the polyQ tract, with an exponential rise-to-maximum and a linear regression, respectively, independently of the conformation of the BlaP moiety, and of the position of the polyQ tract within BlaP. Longer polyQ tracts are likely to have a larger conformational flexibility allowing them to more easily adopt an amyloid-aggregation prone conformation. However, the Q-threshold for fibril elongation is much lower than for fibril formation in solution: the polyQ tract requires a larger conformational flexibility to nucleate the formation of fibrils than to elongate them. Secondly, the Q-threshold for fibril formation is lower once the BlaP moiety is unfolded, and BlaP-polyQ chimeras aggregate faster into amyloid fibrils under conditions favoring the unfolding of the BlaP moiety. The native structure of BlaP is likely to impose conformational constraints to moderate and long polyQ tracts that block and decrease, respectively, their propensity to form fibrils. The effects of constraints decrease with the polyQ length. Thirdly, BlaP chimeras with the polyQ tract in position 216 have an increased propensity to trigger the nucleation and the elongation of amyloid fibrils compared to chimeras with the polyQ in position 197. Advanced studies confirm that the propensity of the polyQ tract to aggregate into amyloid fibrils is linked to the conformational flexibility of the polyQ tract, which depends on (i) the polyQ length, (ii) the location of the polyQ tract within BlaP, i.e., a terminal location or embedded within a protein domain, and (iii) the structural properties of the polyQ flanking regions. Finally, we observe that the whole region flanking the polyQ tract in position 197 at its N-terminus has an anti-aggregating property that fully counterbalances the pro-aggregating property of that flanking at the C-terminus. The former imposes strong conformational constraints to the polyQ tract that reduce its conformational flexibility and hence its aggregation propensity. Moreover, these regions are likely to differently affect the solubility of the polyQ protein and hence the driving force for insoluble aggregation. Altogether, our data also suggest that BlaP chimeras aggregate via the commonly described nucleation-dependent polymerization mechanism during which the aggregation is first triggered by polyQ-polyQ interactions, and then a subsequent slight reorganization of the BlaP moiety is required for conversion of aggregates into amyloid fibrils. Based on these results, we should allow the development of therapeutic strategies, targeting specifically the molecular features of the complex interplay between the polyQ and non-polyQ regions during the nucleation and/or elongation of the pathological aggregation of polyQ proteins. [less ▲]

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See detailPourquoi se mobiliser pour la planète rouge?
Stiepen, Arnaud ULg

Conference given outside the academic context (2015)

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See detailWood, the material of tomorrow's retrofits
Ruellan, Guirec ULg; Attia, Shady ULg

in High-quality retrofit and redensification with timber construction systems (2015, June 18)

The construction sector has focused for many years on performance improvement of new constructions. Today's largest problem is the energetic retrofitting of existing buildings. The building retrofit is an ... [more ▼]

The construction sector has focused for many years on performance improvement of new constructions. Today's largest problem is the energetic retrofitting of existing buildings. The building retrofit is an important strategy for energy savings. Building retrofit is addressed towards the real estate in Europe and allows for substantial gains, especially for heating houses and urban densification. However retrofit requires the use of special construction techniques. The problem is quite different from that of the new buildings: adaptation to existing building, heritage conservation, elimination of thermal bridges, etc. In this context, wood is experiencing strong growth in its use in new constructions, due to its qualities. And we think that some of those allow more appropriate responses to retrofit than other traditional materials. In this study, we will first present succinctly the problems related to the renovation, then we will dedicate ourselves to define the characteristics of the wood. The focus will be on some problems that commonly arise in wood constructions. We will then discuss a case, highlighting different characteristics of wood that are particularly important in this particular renovation. This allows us to observe on the ground the coherence of the choice of wood in the renovation. A discussion will close the study by summarizing the advantages and limitations of the use of wood in the renovation This is not to show that wood is one of the most environmentally friendly building materials, or demonstrate the sustainable character of retrofit. This is to see that the timber construction systems can provide an adequate response to many retrofit issues. [less ▲]

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See detailLa limitation du cumul de mandats par les députés wallons
Grandjean, Geoffrey ULg

in Courrier Hebdomadaire du CRISP (2015), 2255-2256

En moyenne, les représentants politiques belges cumulent entre cinq et huit mandats (dont la moitié sont rémunérés). Cette pratique contribue au développement des sentiments de méfiance que nourrit une ... [more ▼]

En moyenne, les représentants politiques belges cumulent entre cinq et huit mandats (dont la moitié sont rémunérés). Cette pratique contribue au développement des sentiments de méfiance que nourrit une partie de la population à l’égard des élus et des institutions. Dans un souci de bonne gouvernance, de nombreux citoyens et acteurs politiques appellent dès lors à une limitation des possibilités légales de cumul de mandats. La traduction récente la plus emblématique de cette préoccupation éthique est le décret décumul adopté en Région wallonne en 2010. Désormais, un député wallon n’a plus le droit de cumuler son mandat avec une fonction de bourgmestre, d’échevin ou de président d’un conseil de l’action sociale. Un quart des membres de chaque groupe politique représenté au Parlement wallon est cependant autorisé à cumuler. Les députés qui bénéficient de cette exception sont désignés sur la base de leur taux de pénétration électorale. Ce mécanisme est le fruit d’un accord politique conclu entre les partenaires du gouvernement régional (PS, Écolo, CDH). Son adoption a fait l’objet de débats nombreux et souvent tendus entre les partis politiques, en ce compris au sein de la majorité. Ce Courrier hebdomadaire retrace l’ensemble du processus législatif à la base du décret décumul. Il replace l’initiative dans son contexte et analyse le jeu des différents acteurs, en réservant une attention particulière aux divers arguments politiques, techniques et surtout juridiques qui ont été mobilisés. G. Grandjean se penche également sur les effets que le décret a eus pour les députés élus lors du scrutin régional wallon du 25 mai 2014. Enfin, il s’interroge sur l’avenir du décret décumul, que certains voudraient réformer, voire supprimer. [less ▲]

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See detailLe saut d'index, on vire à droite ?
Grandjean, Geoffrey ULg

Conference given outside the academic context (2015)

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See detailScreening and analyzing retrofit systems for zero energy renovation and their potential application in Liège, Belgium
Attia, Shady ULg

in AEE INTEC (Ed.) High-quality retrofit and redensification with timber construction systems (2015, June 18)

Retrofit systems for Zero Energy Renovation comes energy as the most topical subject in the Belgian construction sector. Concepts and solutions for zero energy renovation are a new topic. Since 2006 ... [more ▼]

Retrofit systems for Zero Energy Renovation comes energy as the most topical subject in the Belgian construction sector. Concepts and solutions for zero energy renovation are a new topic. Since 2006, Belgium has been striving to achieve the European ambitions of fulfilling the Kyoto Protocol by insulating more effectively and reducing CO2 emissions associated with the use of fossil fuel for operational and embodied energy in buildings. In 2011, a Belgian decree mandated the construction of nearly zero and nets zero energy buildings by 2020. Following the German PassivHaus Standard performance requirements the Belgian residential sector is aiming to achieve an energy consumption to less than 15 kWh/m2/year and an onsite renewable energy production up to 60% for every newly construct household. In this, context the study will build on grounded knowledge developed and implemented by the IEA ECBCS Annex 50: Prefabricated Systems for Low Energy Renovation of Residential Buildings. The goal of this research is to screen and select a series of envelope retrofitting solutions. The focused aim is to demonstrate validated envelope prototypes and products of different zero energy, timber frame construction systems and composite components. This will include the comparison of timber retrofit systems with conventional systems. Thus inform and support the decision making of policy makers, municipalities, developers, and architects and building engineers in Belgium. [less ▲]

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See detailUncertainty of climate change impact on groundwater reserves – Application to a chalk aquifer
Goderniaux, Pascal; Brouyère, Serge ULg; Wildemeersch, Samuel et al

in Journal of Hydrology (2015), 528

Recent studies have evaluated the impact of climate change on groundwater resources for different geographical and climatic contexts. However, most studies have either not estimated the uncertainty around ... [more ▼]

Recent studies have evaluated the impact of climate change on groundwater resources for different geographical and climatic contexts. However, most studies have either not estimated the uncertainty around projected impacts or have limited the analysis to the uncertainty related to climate models. In this study, the uncertainties around impact projections from several sources (climate models, natural variability of the weather, hydrological model calibration) are calculated and compared for the Geer catchment (465 km2) in Belgium. We use a surface–subsurface integrated model implemented using the finite element code HydroGeoSphere, coupled with climate change scenarios (2010–2085) and the UCODE_2005 inverse model, to assess the uncertainty related to the calibration of the hydrological model. This integrated model provides a more realistic representation of the water exchanges between surface and subsurface domains and constrains more the calibration with the use of both surface and subsurface observed data. Sensitivity and uncertainty analyses were performed on predictions. The linear uncertainty analysis is approximate for this nonlinear system, but it provides some measure of uncertainty for computationally demanding models. Results show that, for the Geer catchment, the most important uncertainty is related to calibration of the hydrological model. The total uncertainty associated with the prediction of groundwater levels remains large. By the end of the century, however, the uncertainty becomes smaller than the predicted decline in groundwater levels. [less ▲]

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See detailRhizobacterial volatiles influence root system architecture, biomass production and allocation of the model grass Brachypodium distachyon (L.) P. Beauv.
Delaplace, Pierre ULg; Ormeño-Lafuente, Elena; Delory, Benjamin ULg et al

Conference (2015, June 18)

Plant growth-promoting rhizobacteria are increasingly considered as a complement of conventional inputs in agricultural systems. Their effects on their host plants are diverse and include volatile ... [more ▼]

Plant growth-promoting rhizobacteria are increasingly considered as a complement of conventional inputs in agricultural systems. Their effects on their host plants are diverse and include volatile-mediated growth enhancement. The present study aims at assessing the effects of bacterial volatile production on the biomass production and the root system architecture of Brachypodium distachyon (L.) Beauv. (line Bd-21). An in vitro experimental set-up allowing plant-bacteria interaction through the gaseous phase without any physical contact was used to screen 19 bacterial strains for their growth promotion ability over a 10-day cocultivation period. Using principal component analysis followed by hierarchical clustering and two-way analysis of variance, five groups of bacteria were defined and characterized based on their combined influence on biomass production and root system architecture. The observed effects range from unchanged to highly increased biomass production coupled with increased root length and branching. Primary root length was only increased by the volatile compounds emitted by Enterobacter cloacae JM22 and Bacillus pumilus T4. Overall, the most significant results were obtained with Bacillus subtilis GB03 which induced a 81% increase in total biomass and enhanced total root length, total secondary root length and total adventitious root length by 88, 196 and 473% respectively. The analysis of the emission kinetics of bacterial volatile organic compounds is underway and should lead to the identification of volatile compounds candidates responsible for the observed growth promotion effects. Taking into account the inherent characteristics of our in vitro system, the next experimental steps are identified and discussed from a fundamental and applied viewpoint. [less ▲]

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See detailOverview and recommendation on urban densification potential in Liège, Belgium
Attia, Shady ULg

in AEE INTEC (Ed.) High-quality retrofit and redensification with timber construction systems (2015, June 18)

Belgium, like many European Countries, has a serious challenge in the housing sector. The Federal planning bureau estimates the increase of population by one million inhabitants by 2030, which represent ... [more ▼]

Belgium, like many European Countries, has a serious challenge in the housing sector. The Federal planning bureau estimates the increase of population by one million inhabitants by 2030, which represent 600.000 additional family requiring accesses to new housing facilities. Population ageing (mainly due to increasing life expectancy) combined with a constant growing rate of individuals living in collective households, leads to a substantial increase of demand of collective households (Vandresse & Bureau, 2013). This highlights a substantial challenge underlined mainly in the need to live in cities, which as consequence will increase the demand for smaller housing with or without integrated services or equipment in common. Furthermore, the stringent European performance environmental regulations for the building sector require that by 2020, all new construction are zero or nearly zero energy, (equivalent to 15 kWh/m2/year), with 60% efficient on-site coverage by renewable energy. The shortage of vacant land and the increasing energy performance requirements is pushing the idea of urban densification and zero energy construction households. During the recent 6 years, there has been a trend to use timber frame constructions as a sustainable solution facing the economic and environmental crisis in Belgium. However, there is lack of knowledge on the design, construction and operation of zero energy lightweight constructions for urban densification. The goal of this research is to provide an overview and recommendation on urban densification potential in Liège Province. The focused aim is to demonstrate validated design prototypes and products of different zero energy, timber frame construction systems and composite components. Thus inform and support the decision making of policy makers, municipalities, developers, and architects and building engineers in Belgium. [less ▲]

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See detailLandscape Control on the Spatial and Temporal Variability of Chromophoric Dissolved Organic Matter and Dissolved Organic Carbon in Large African Rivers
Lambert, Thibault ULg; Darchambeau, François ULg; Bouillon, Steven et al

in Ecosystems (2015)

The characteristics of colored dissolved organic matter (CDOM) as well as the concentrations and stable isotope composition (d 13 C) of dissolved organic carbon (DOC) were characterized in several large ... [more ▼]

The characteristics of colored dissolved organic matter (CDOM) as well as the concentrations and stable isotope composition (d 13 C) of dissolved organic carbon (DOC) were characterized in several large rivers of Africa including the Congo, Niger, Zambezi, and Ogooué basins. We compared the spatial and temporal patterns of dissolved organic matter (DOM) quantity and quality along with various environmental gradients, including hydrology, river size, catchment vegetation, and connectivity to land. The optical proxies used include the absorption coefficient at 350 nm, the specific ultraviolet absorbance, and the spectral slope ratio (S R = 275–295-nm slope divided by 350–400-nm slope). Our results show that land cover plays a primary role in controlling both DOC concentration and optical properties of DOM in tropical freshwaters. A higher cover of dense forest in the catchment leads to a higher quantity of highly aromatic DOM in the river network, whereas an increasing savannah cover results in lower DOC concentrations and less absorptive DOM. In addition to land cover, the watershed morphology (expressed by the average slope) exerts a strong control on DOC and CDOM in tropical rivers. Our results also show that the percentage of C3 and C4 vegetation cover is not an accurate predictor for DOM and CDOM quality in rivers due to the importance of the spatial distribution of land cover within the drainage network. The comparison of our results with previously published CDOM data in temperate and high-latitude rivers highlights that DOM in tropical freshwa-ters is generally more aromatic, and shows a higher capacity for absorbing sunlight irradiance. [less ▲]

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See detailGeorges Ier d’Amboise, amateur d’art
Fagnart, Laure ULg

Conference (2015, June 18)

Figure emblématique de la Renaissance rouennaise et normande, Georges Ier d’Amboise rassemble, on le sait, une bibliothèque exceptionnelle, notamment constituée de manuscrits ayant appartenu aux rois ... [more ▼]

Figure emblématique de la Renaissance rouennaise et normande, Georges Ier d’Amboise rassemble, on le sait, une bibliothèque exceptionnelle, notamment constituée de manuscrits ayant appartenu aux rois aragonais de Naples. Le cardinal s’intéresse également à l’architecture, comme peu de ses contemporains, privilégiant les formes et les fonctions nouvelles, spécialement celles en vigueur en Italie. Il participe aussi à la fortune française d’artistes italiens de renom, comme Andrea Mantegna, Léonard de Vinci, Pérugin ou Andrea Solario, dont il commande ou acquiert des œuvres afin de décorer ses demeures, le château de Gaillon en tête. Mais, alors que son rôle dans la diffusion, au nord des Alpes, des idées et des motifs venus d’Italie est indéniable, le portrait de Georges Ier d’Amboise amateur d’art comprend bien d’autres facettes. Prolongeant une recherche entamée à l’occasion de la parution de l’ouvrage Georges Ier d’Amboise 1460-1510. Une figure plurielle de la Renaissance (2013), cette communication entend revenir sur les objets et les œuvres d’art que l’on peut associer au mécénat et/ou aux possessions de l’archevêque de Rouen. Nous nous pencherons sur les productions italiennes qui sont liées à Georges Ier d’Amboise mais aussi sur les étoffes, les pièces d’orfèvrerie et les tableaux de chevalet, qui sont mentionnés en nombre dans les comptes de dépenses de la construction du château de Gaillon et dans les inventaires qui décrivent les biens meubles conservés dans les demeures du cardinal. L’analyse de ces sources – que jusqu’ici les historiens ont surtout utilisées pour restituer la chronologie du château de Gaillon, rétablir la distribution intérieure de la demeure ou décrire la célèbre bibliothèque du légat alors qu’elles se révèlent extrêmement précieuses pour présenter les collections du conseiller de Louis XII – montre que le goût de Georges Ier d’Amboise, bien que novateur, s’inscrit aussi dans la continuité de celui des amateurs français de la fin du Moyen Âge. [less ▲]

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See detailDes co-enquêteurs coriaces. Quand l'explicitation du travail de terrain complique les choses
Vangeebergen, Thomas ULg

Conference (2015, June 18)

La souplesse et la plasticité des problématiques abordées sont sans doute parmi les attraits majeurs que peuvent présenter les recherches qualitatives. Cette ouverture à une reconfiguration permanente des ... [more ▼]

La souplesse et la plasticité des problématiques abordées sont sans doute parmi les attraits majeurs que peuvent présenter les recherches qualitatives. Cette ouverture à une reconfiguration permanente des questions de recherches réside (entre autres) dans la place que l'on accorde aux acteurs. Plus que des « informateurs », ceux-ci peuvent participer véritablement à l'enquête, et sont alors en fait à la manoeuvre autant que le chercheur. D'acteurs, ils gagnent alors le statut de co-enquêteur. En nous renvoyant nos propres questions, en les reformulant, en les faisant apparaître sous un angle différent, les acteurs contribuent à (re)dessiner nos recherches. [less ▲]

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See detailCharacteristics and implementation of Hybrid Fire Testing (HFT)
Sauca, Ana ULg; Gernay, Thomas ULg; Robert, Fabienne et al

Conference (2015, June 18)

This presentation is dedicated to real time hybrid testing of building members subjected to the action of fire. It will be shown why, whereas pseudo-dynamic testing is possible in other fields, real time ... [more ▼]

This presentation is dedicated to real time hybrid testing of building members subjected to the action of fire. It will be shown why, whereas pseudo-dynamic testing is possible in other fields, real time hybrid testing is the only possible option for the evaluation of fire performance (except, perhaps, for pure metallic unprotected structures). For some structures subjected to fire, the load bearing mechanism in the physical component is completely modified during the test and this modification can take place within a very short period of time. Because of that, the computational demand can be very challenging if the simulated element is simulated in a fully nonlinear computer model, especially if the thermal problem (temperature distribution in the structure) and the mechanical problem have both to be solved within each time step. In order to avoid these difficulties, a possible solution may be to calculate the stiffness matrix that dictates the reaction of the simulated element on the tested element before the test. This matrix can be constant or vary as a function of the displacements measured at the interface during the test. This procedure is very robust but it also has some shortcomings and limitations. The main topic of this paper is the discussion of the advantages and limitations of this procedure applied to hybrid fire testing. A series of three tests which is now under preparation to be performed in the furnace PROMETHEE of CERIB, in France, will also be described in this respect. Preliminary results will be presented if some or all of the tests have been performed at the date of the conference. [less ▲]

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