Дисертації з теми "Construction en pierre – Conservation et restauration"
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Nougayrede, Paul. "Analyse et conception des structures clavées : approches théoriques et investigations numériques." Electronic Thesis or Diss., Paris Est, 2023. http://www.theses.fr/2023PESC2018.
The current context urges the various players in the field of architecture and construction to increasingly question architectural design methods and production technologies, regarding issues linked to climate change and the scarcity of resources. That's why for a few decades there has been a renewed interest for using stone material, for several reasons (mechanical qualities, important durability, potential local resource...) and in particular for stereotomic masonry structures made up of stone voussoirs, cut and fitted. The fascinating properties of these different types of structures (arches, vaults, domes, jack arch, etc.) are still the subject of a great research diversity today which implements different approaches in order to model their stability, depending on the different cases. The advanced modeling of these monuments then makes it possible to fuel in-depth reflection on the design of new typologies of stone structures (mixed structures, reciprocal structures, collages, optimization of shape, use of material) and not only on the mechanical diagnosis of the existing. Two types of block-to-block modeling are thus implemented in this work. The Finite Element Method (FEM) makes it possible to simulate the deformations and stresses into blocks and mortar joints, via mathematical routines firmly anchored in structural research since the very first computers. Advanced modeling by the FEM is carried out as part of the scientific project to evaluate the stability of the vaults of Notre Dame de Paris cathedral, following the 2019 fire. The use of Limit Analysis modeling (LA) makes it possible to circumvent the difficulties in FEM: greedy calculation resources, complex implementation and processing results. LA is used, on the contrary, to determine relatively easily and quickly a stability domain based solely on the assumptions of (i) the geometry of the blocks, considered as infinitely rigid, (ii) the failure criteria at the joint interfaces and (iii) ) the external loads. The application of this method has found echo in a long tradition of heritage masonry structures studies which have thus been able to demonstrate its effectiveness, despite a compromise on the nature and precision of the answers, relative to other non-linear methods such as FEM.The AL approach is therefore implemented in the most general possible way by relying on advanced mathematical resolution tools (conic programming), with the aim of making its use accessible to as many users as possible (architects, historians, stone cutters, engineers…). Several concrete case studies using the FEM approach and the AL approach in parallel show the advantages and limitations of the latter depending on the applications
Genet, Paul-Edgard. "Impact des interventions humaines sur l’érosion des calcaires monumentaux du secteur Río Bec (Campeche, Mexique)." Thesis, Université Clermont Auvergne (2017-2020), 2019. http://www.theses.fr/2019CLFAL018.
The Mayan archaeological sites in the Río Bec sector are characterized by a high conservation challenge, due to the low durability of limestone built materials and to the high level of atmospheric stresses to which they are being subjected. Moreover, human interventions carried out on built heritage in the sector since its rediscovery are likely to constitute an anthropogenic forcing on weathering processes and rates, which we aimed to identify, spatialize and quantify. Different steps of this research include archives work compilation, GIS mapping, petrographic analysis and 3D modelling by photogrammetry. Main results show that human interference is much more likely to modify weathering processes and rates than the mere exposure of stone materials to atmospheric agents. The harmful effects of some interventions, such as cement repointing, have been demonstrated, and the effects of colonizing organisms on the stone surface have been assessed. Finally, new insights and perspectives have been provided on very localized restorations causing drastic changes of weathering regimes within a very restricted area
Genis, Léa. "Réhabiliter le bâti ancien et les cultures constructives : engagements, épreuves et attachements autour de la réhabilitation du bâti ancien en pisé en Isère." Thesis, Université Grenoble Alpes (ComUE), 2018. http://www.theses.fr/2018GREAH018/document.
Ancient buildings face today normative, environmental and patrimonial issues which foster their renovation and engage a great diversity of actors. This multiplicity initiates a debate around knowledge, professional worlds and attachments which are woven around existing buildings. This thesis delves into these dynamics focusing on the case of ancient rammed earth building (raw earth compressed into an external formwork) in the French department of Isere, France. It aims at describing how and by whom rammed earth buildings are involved in retrofitting projects, considering both their physical and representational improvement. We make the hypothesis that retrofitting projects, through the multiple ways of engagement they imply, help to free the experience of this buildings from an ordinary experience. Indeed, they put on trial the attachments developed by the actors around existing buildings and earthen material as much as the building knowledge and practices. These trials bring out collectives that weave a political meshwork. At different scales, this meshwork composes spaces for dialogue and appropriation of uses, practices and futures of existing buildings.The exploration of this hypothesis follows an interdisciplinary perspective that connect theoretical resources and methods developed in architecture, ethnology and sociology. It develops a pragmatic anthropology of building cultures composing a common problematic for these disciplines to discuss ancient building retrofitting. The investigation is based on multi-sited qualitative ethnography. Following projects paths carried by different actors (inhabitants, professionals, institutions), it describes the retrofitting worlds in action. First, the thesis describes the various forms of engagement in retrofitting projects, from the intervention on a specific building to its evaluation as heritage. These experience draw attention on different qualities of the buildings and bring them out of their ordinary status. Ancient rammed earth buildings are therefore engaged – and engage themselves – in multiple realities: house, place of life, workplace, local heritage, earthen architecture. It makes the actors act, react and interact. Then, the analysis shows how the difficulty of applying strict rehabilitation protocols leads the actors to engage in trials and to develop holds to carry out their projects. As the project progresses, these trials lead them to adjust their relations with each other and with existing buildings. As they grasp knowledge about retrofitting, they develop different attachments. Therefore, retrofitting projects contribute to the emergence of collectives, more or less durable. At their own scale, these collectives reclaim the methods of interventions on buildings and the decision that concern them. The thesis eventually aims to better understand the plural dimensions (material, constructive, architectural and interactional) of rammed earth building retrofitting and propose components for a dialogue to carry on with local stakeholders around the interests and conditions that would make possible to hold a political space around the uses and futures of existing buildings
Bernabé, Emmanuelle. "Les mécanismes d'altération des monuments historiques en environnement océanique et rural : application à la conservation de l'église Saint Nonna de Penmarc'h et de Basilique Notre-Dame du Folgoët." Aix-Marseille 3, 1996. http://www.theses.fr/1996AIX30123.
Callais, Chantal. "De l'équipement public au monument historique, les architectes et la fonction publique d'Etat au XIXe siècle : à corps perdu, Pierre-Théophile Segretain architecte, 1789-1864." Versailles-St Quentin en Yvelines, 2009. http://www.theses.fr/2009VERS024S.
Trained in Paris with Louis Bruyère, after one year at Polytechnique, Segretain joined his native Deux-Sèvres, where he is nominated as architect of the Department at the age of 26 years. Fascinated by the new programs of Public Works, he commits himself, with the total confidence of his Inspector General Mérimée, enthusiastically to the first restorations of historic buildings. Nourished by the culture of public service transmitted by his Master, he defends the idea of the creation of a hierarchically structured body of State architects, just like the civil engineers, that will however, never see the light of day except in the field of cultural heritage. By comparing the status of the “architects of the government” on the whole of the French territory, outside Paris, during the XIXth century, it is possible to identify variations and common points between the departmental services of the civil building which entrusted to the local government increasingly move away from the central state control
Boucher, Denis. "Sauvegarde du patrimoine, commémoration du passé et construction d'une mémoire locale : Rivière-du-Loup et le manoir Fraser." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 2001. http://www.collectionscanada.ca/obj/s4/f2/dsk3/ftp04/MQ61332.pdf.
Prieto, Sonia. "Nouvelle approche de la polychromie architecturale : sources et méthodologies d'une pratique artistique et sociale à l'époque contemporaine." Paris 8, 1992. http://www.theses.fr/1992PA080719.
This work closely follows the historical evolution of the principal architectural styles in the contemporary epoch and the technical discoveries concerned. But it treats in particular the manifestations of the architectural polychromatics (wich constitutes the focus of the research), and it refers, first; to the classical antiquity in its contemporary interpretations, thereafter studying the eclecticism, the employment of materials like brick and its derivatives, and modern'style, movements that have confered chomatical diversities upon the urban space, up to the birth of the colourless functionalism (with finds its active contestors, the folleowers of the coloration of the facades). Passing in review are the movements of modern art, where the principal preoccupation has been the integration of colour in architecture. This development has led to a new artistic (and social) practice of architectural polychromatics, exercised by plastic artists who have elaborated new operational methods for colouring the built environment
Kerouanton, Jean-Louis. "Investissement religieux et architecture en Maine-et-Loire : 1840-1940 : les églises paroissiales." Rennes 2, 1998. http://www.theses.fr/1998REN20019.
The rebuilding of parish churches is a phenomenon which particularly affects the west of France in the XIXth century. More than two third of Maine-et-Loire parishes, which confuse with Angers'diocese, are concerned by this rebuilding between 1840 and 1940. But it's in fact nearly the whole territory which is concerned all those works realised. This study, realised thanks to catalogue published by each parish, applies not only to the most important and large works campaigns but also to the most modest such as repairing or expansions. Then different actors, priests and architects, " fabriques ", towns, state, intervene with their complementarities or their oppositions. The geography taking shape not only takes care of the practical and religious attitudes, with a traditional eastern and western dichotomy in Maine-et- Loire. The geography leads up to a different logic which is more adapted to public and council equipments, answering to the population needs
Michel, Laura. "Méthodologie d’analyse structurelle et de restauration d’oeuvres sculptées." Thesis, Orléans, 2013. http://www.theses.fr/2013ORLE2068/document.
Currently, the artworks restoration, including broken statues, are based on proven but empirical techniques. Damaged statues often have broken parts. Restoration mainly consists in joining these parts. Thus appears the necessity of taking into account the interfaces mechanical properties between the different broken parts, reducing thereby the extent of repairs and thus better maintain the integrity of the work. Beside this, digital 3D acquisition techniques become more and more popular among the cultural heritage community. This thesis proposes a methodology able to use 3D acquisition datas to simulate the restoration operations and their effects on the structure. The restoration strategy can thus be tested and optimized. A laser scanner is used to acquire the statue geometry, allowing to reconstruct a 3D model for numerical simulation. Computations are carried out within the framework of deformable continuum mechanics using the FLAC3D software. In order to check all the key points ensuring mechanical stability, the behavior of reinforcing elements and those of the interfaces between blocks were considered. From the results of the present studies, a critical analysis of implemented or possible restoration strategy is proposed. In addition, several characterization methods to find the material origin and/or estimate the mechanical properties of the work are proposed : physico-chemical and mineralogical characterizations, non-destructive and destructive tests. An experimental campaign to characterize the behavior of fractures in contact with surface acquisition was performed. An analysis of correlations between mechanical and morphological interfaces properties is then developed. Finally, we propose a predictive modelling based on multiple linear and multivariate regressions. This study allow the simulation of fractured artworks behaviour
Trempe, Richard. "Réhabiliter l'enveloppe du bâtiment au Québec : impact des considérations sociales et techniques sur l'analyse de la performance." Master's thesis, Université Laval, 2016. http://hdl.handle.net/20.500.11794/26746.
Paulhiac, Florence. "Le rôle des références patrimoniales dans la construction des politiques urbaines à Bordeaux et Montréal." Phd thesis, Université Michel de Montaigne - Bordeaux III, 2002. http://tel.archives-ouvertes.fr/tel-00265082.
Une innovation est notamment repérée à travers le cas de la reconversion du Vieux Port de Montréal , celle de la constitution d'une trame patrimoniale, produite à l'occasion d'une planification négociée et participative.
Piri, Saeid. "Restauration du bazar de Hamadan (Iran)." Thesis, Paris, CNAM, 2013. http://www.theses.fr/2013CNAM0919.
Many big cities in Iran, have thousands years background and yet some parts of ancientsites and monuments that several centuries old are existing. Many of this textures andmonuments because of using vulnerable materials like brick and mud brick and also land usechanges in urban area are being changed and destroyed. Bazaar has been the most importantconnection way and Iranian urban spaces. According to the existing document, you can guessthat historical background of Bazars is related to thousand years B.C. until the first period ofcurrent century, Bazaars in each city had an organic and strong relation with other urbanspaces. But from the beginning of current age, after urban development and constructing ofroads and streets and establishing new methods of residency and urbanism, their relation withanother urban spaces has disjoined. Nowadays Hamadan bazaar is active, but due to the somesocioeconomic problems, some part of it is going to be deserted. The objective of study ofHamadan bazaar is determining the body and operation and some socioeconomiccharacteristics and finding solution for improvement as follow result. A) Predicting offacilities for further new activities. B) presenting standard and regulation for improvement ofconstruction and C) omitting misfit operation and activities
Fiori, Ruth. "La construction d'une conscience patrimoniale parisienne à la fin du XIX siècle : acteurs, pratiques et représentations (1884-1914)." Paris 1, 2009. http://www.theses.fr/2009PA010572.
Aalil, Issam. "Contribution à l’étude du patrimoine bâti. Méthodes de diagnostic des pathologies des structures et moyens de restauration : Etude de cas. Site archéologique Volubilis au Maroc." Thesis, Orléans, 2017. http://www.theses.fr/2017ORLE2067/document.
The restoration of the built heritage is mandatory to ensure its sustainability. The archaeological site of Volubilis in Morocco, registered on the UNESCO World Heritage list since December 1997, requires restoration works. The main objective of this thesis is to determine the causes of stones’ deterioration and to propose mortars for restoration of its monuments. Firstly, a multi-scales characterization study was carried out on the three facies of the calcarenite, the main building stone in the site. It showed that despite their similar mineralogical composition, the three facies have dissimilar hydric, thermal and mechanical properties and they are quite different in terms of durability against salt crystallization. Besides, non-destructive testing could be used to distinguish the three facies by estimating their porosities and their coefficients of capillarity. Secondly, a diagnosis study revealed the presence of halite and gypsum in most deteriorated stones affected by detachment and loss of material. These salts originated from neighboring mortars, used during the previous interventions. In addition, the deterioration of uncontaminated calcarenites is likely due to thermal stresses. In the last part, we formulated mortars using lime, sand and the brick dust using the mixtures method. This approach would determine compatible mortars to the stone calcarenite
Roy, Alain. "Le Vieux-Québec, 1945-1963 : construction et fonctions sociales d'un lieu de mémoire nationale." Master's thesis, Université Laval, 1995. http://hdl.handle.net/20.500.11794/23871.
Bechetoille, Soizik. "Reconstructions et restaurations des monuments en bois. Les techniques traditionnelles du Japon face aux enjeux de la modernisation, de la construction du sanctuaire de Heian à Kyōto (1894) à la reconstruction du pavillon de l'Ultime Suprême de l'ancien palais impérial de Nara (2010)." Thesis, Paris Sciences et Lettres (ComUE), 2018. http://www.theses.fr/2018PSLEP072/document.
This research addresses the issue of authenticity through restoration practices on Japanese architectural heritage and focuses mainly on traditional wooden buildings under restoration. One of the particularities of architectural practice in Japan is certainly the periodic dismantling of old buildings. The origins of this traditional practice stems from harsh climatic conditions, specificities related to wooden architecture, or ancient religious practices including the periodic reconstruction of some Shinto shrines. This “non-permanence” of buildings allows the transmission of forms and techniques through ages and time. With the concept of “reconstruction” comes the idea of building “once again” what was destroyed, as well as restoring, reproducing or restoring a primitive form, a structure or a building from fragmentary elements (vestiges, epigraphic sources, etc.). This presupposes the creation of a completely new object – with unprecedented materiality – that is triggered by the idea of making "once again" something that already existed. This definition of “reconstructing” invites us to consider a possible coexistence of different types of practices and standards of reconstruction. The act of “reconstruction - restitution” is often invoked to retrieve a missing “savoir-faire” (technical know-how). For many specialists, the practice of restoration by disassembling (prior to reconstructing) constitutes (or involves) the synthesis of techniques and theories related to traditional architecture. The aim of this research work is thus to study different cases of building reconstruction and type of practices that drive them
Dutour, Juliette. "La construction du patrimoine du Canada entre reconnaissance publique et valorisation touristique : le rôle de la Commision des lieux et monuments historiques du Canada et des organismes de tourisme canadiens (1919-1956)." Paris, EHESS, 2008. http://www.theses.fr/2008EHES0014.
The aim of this thesis is to demonstrate that Canadian heritage policies and practices emerge, at the very beginning of the century, largely as the result of a tension between the political will to construct a national identity and economic concerns that encourage the government to invest into international tourism. The following study will examine the joint actions of the Historic Sites and Monuments Board of Canada, the first and main heritage institution in Canada and of tourist organizations, particularly the Canadian Tourism Association and the Canadian Government Travel Bureau. Created in 1919, the Board holds the mandate to identify sites and important national events, which require commemoration, safeguarding and protection by the government. However, lacking financial resources, the Board's action was limited to the establishment of monuments and plaques at historical sites and to the commemoration of historical heroes and events for the country's inhabitants and tourists. Shortly after the Second World War, Canada experienced a sharp increase in tourism. These historical sites were transformed into tourist attractions, which prompted the federal government to acknowledge the problem caused by the slow degradation of the sites due to neglect. The activism of tourist organizations led to the establishment of the first Historic Sites and Monuments Act in 1953, followed by other legislation in 1955 and 1956. This study contends, then, that tourism has played a role as important as public policies in safeguarding historical architecture and in raising public awareness to heritage
Roser, Sandrine. "L'art à l'abbaye de Baume-les-Messieurs dans la première moitié du XVe siècle." Besançon, 2003. http://www.theses.fr/2003BESA1036.
Au XVe siècle, la restauration de l'abbaye de Baume (Jura), ruinée depuis 1336, fut le fait de deux abbés : Amé de Chalon (1389-1431) et Henri de Salins (1431-1451 ?). Après avoir redressé le temporel, le premier restaura dès 1399 les bâtiments conventuels, l'église et sans doute une partie du cloître. Pour le chantier, il utilisa le système des corvées et exploita les proches carrières de Crançot. Le réfectoire et de nombreux vestiges des importants aménagements liturgiques qu'il fit réaliser subsistent : des stalles, trois autels, de nombreuses statues ayant appartenu au jubé, à l'autel majeur et à sa chapelle particulière, inspirées d'œuvres de Dijon ou Poligny. L'abbé fit ériger son somptueux tombeau sous une arche, au nord du sanctuaire, orné de peintures murales et de plusieurs sculptures. Son successeur éleva l'actuelle façade occidentale de l'église, dotée de statues et restaura une vaste chapelle mariale hors-œuvre, typique de l'architecture clunisienne, et s'y fit inhumer
Patigny, Géraldine. "L'atelier bruxellois des du Quesnoy :catalogue raisonné et pratiques d'atelier." Doctoral thesis, Universite Libre de Bruxelles, 2020. https://dipot.ulb.ac.be/dspace/bitstream/2013/304924/5/Table.docx.
Doctorat en Histoire, histoire de l'art et archéologie
info:eu-repo/semantics/nonPublished
Gibeaux, Soizic. "IFEPAR - Impact des Facteurs Environnementaux sur le Patrimoine Restauré." Thesis, Reims, 2017. http://www.theses.fr/2017REIMS046.
The IFEPAR project focuses on the impact of new concentrations of atmospheric pollutants on the restored heritage of Reims (France) in order to assess the current alteration kinetics and to anticipate the future restorations on monuments. For this purpose, a multi-scale approach was carried out. At the scale of restored monuments, a continuous monitoring of temperature, relative humidity and atmospheric pollutants through the development of a network of autonomous sensors network and data transfer (3G), and a periodic monitoring of the surface conditions of the façade stones have been set. At the scale of the samples and the porous network of the original and the restoration stones, laboratory accelerated ageing tests by atmospheric deposition and acid solutions were carried out. The micro-environmental monitoring of monuments is now possible. It pointed out the existence of significant differences between two façades of the same monument and sometimes higher values compared to background data (ATMO). Monitoring of the surface conditions by NDT showed little differences in 2 years, even if the restored surfaces appear less reactive than the altered surfaces. The ageing tests simulating different ratios of NOx and SO2 and illustrating the inversion observed in recent decades show that the concentration of SO2 remains decisive in the processes and kinetics of alteration. The microscopic study under HRXCT allowed a prediction of the microstructural behavior of stones in the long term. This study demonstrates the importance of linking in situ monitoring with in-depth laboratory studies
Hellebois, Armande. "Theoretical and experimental studies on early reinforced concrete structures: contribution to the analysis of the bearing capacity of the Hennebique system." Doctoral thesis, Universite Libre de Bruxelles, 2013. http://hdl.handle.net/2013/ULB-DIPOT:oai:dipot.ulb.ac.be:2013/209441.
With this in mind, the present research aims at identifying the specific structural characteristics of reinforced concrete structures erected before the First World War. Several axes of investigation were pursued in this PhD research and have resulted in the main observations detailed below.
- Based on a case study of the region of Brussels (Belgium), a database of structures built in reinforced concrete prior to 1914 was drawn up in order to place the material in its historical and geographical context. The inventory currently contains 507 examples and provides a panorama of the uses of reinforced concrete, ranging from numerous foundations and slabs to a complete structure from the end of the 1890s. This list is supplemented by a survey of a total of 605 patents filed for reinforced concrete in Belgium before the First World War. The early development of reinforced concrete was strongly related to national patenting, with a considerable number of systems being patented by private inventors for commercial purposes. Reinforced concrete profoundly transformed the building industry. All the professions working with the composite material had to change their approach, from the planning stage through to execution on the site. From the viewpoint of construction history, all these modifications make the time of the advent of reinforced concrete a particularly fruitful period to study.
- From the survey of early reinforced concrete structures in Brussels and the database of Belgian patents, the supremacy of the Frenchman François Hennebique and his system on the Brussels market for reinforced concrete (and, by extension, on the Belgian market) before 1914 is incontestable. This commercial achievement resulted from a combination of factors: an efficient structural system, meticulous attention to the quality of on-site reinforced concrete execution, and the commercial acumen to develop the business through advertising and other media. The well-known Hennebique system represents a monolithic structure including slabs, beams and columns. In fact, this system changed over the decades of operation of Hennebique’s company, not so much in relation to the design methods (his original semi-empirical method continued to be used) but particularly in practical terms (the type and location of the rebars among others). The evolution of the system is analysed by means of technical drawings from about 30 Belgian projects designed by Hennebique between 1900 and 1930.
- After the building contractors, who had been the first to believe in the structural and economic potential of reinforced concrete, engineers invented the calculation models and architects started developing new shapes. The Belgian engineer Paul Christophe was among the first theorists of reinforced concrete. The publication of his book Le béton armé et ses applications in 1899 is internationally recognised as a milestone in the rational modelling of structural reinforced concrete elements. Prior to the present study, details of his life and work remained largely uninvestigated, but the discovery of large parts of his personal archives has allowed clarification of his role in the popularisation of reinforced concrete, especially at the theoretical level.
- Reinforced concrete structures around the beginning of the 20th century were initially governed by empirical models of calculation (and execution) developed by the individual constructors. Gradually, reinforced concrete standards, published between 1904 and 1923 and based on working stress analysis and elastic modular ratio theory, replaced the utility of the patented systems. The different theoretical approaches are briefly described in this research. Mastering the theoretical assumptions and calculation methods used at the time represents the first step towards an appreciation of the structural behaviour and the possible weaknesses that can be expected.
- A review, based on literature published at that time, of the properties of the components of reinforced concrete allows identification of the characteristic materials used in the concrete matrix and the metal reinforcements. The execution process and the available technological tools for erecting a reinforced concrete structure are also addressed, as these would have had a direct influence on the quality of construction. Non-destructive and destructive experimental laboratory tests were performed on original samples, mainly removed from the Colo-Hugues viaduct (1904, Braine-l’Alleud, Hennebique system) in order to assess the mechanical properties, chemical features and durability issues for concrete and ferrous reinforcements. Comparing the results obtained using different techniques also makes it possible to determine the extent to which these techniques are reliable for the appraisal of early reinforced concrete structures.
- The structural efficiency of the Hennebique system is assessed based on an understanding of the principles of Hennebique’s semi-empirical method of calculation, but also – and primarily – by means of observations from experimental tests carried out on full-sized beams removed from the Colo-Hugues viaduct. Analysing and understanding the behaviour of the new composite material was a critical issue for promoting the use of reinforced concrete at the beginning of the 20th century. Today, what is required is a re-assessment of its structural behaviour. Three bending tests up to failure in simply supported conditions were performed at the BATir Department of the Université libre de Bruxelles on T-beams from the Colo-Hugues viaduct. This case study is representative of the majority of Hennebique structures, because the typical continuous straight T-beam is the main structural element of any Hennebique structure (bridge, building, etc.). The first test is a four-point bending test on a complete span (6 m) of the viaduct to obtain the response of the central part under positive bending moment. The flexural failure was ductile and occurred through yielding of the reinforcements followed by crushing of the concrete at mid-span. The second and third tests are three-point bending tests on 4 m long specimens centred on the column, representing the behaviour of the beam around the supports. These showed a sudden slipping failure due to loss of the adhesive bond between rebars. The results of these three experiments combined reproduce the actual behaviour of the viaduct in service. The bearing capacity of the Hennebique system in service and at ultimate has been demonstrated, at least for one loading case. These experimental tests provide essential data for a better understanding of the mechanisms of failure and reveal the main weaknesses of the Hennebique T-beam. Two strengthening solutions are suggested as supplementary information.
- The pathologies observed in early reinforced concrete structures (honeycombs, corrosion of the rebars, and so on) are mainly attributable to the tools and techniques that the builders had at their disposal (handmade compaction, high water-to-cement ratio, etc.) and by the limited contemporary knowledge of the physical and chemical phenomena, especially with regard to long-term effects. In fact, the concrete quality of the viaduct is surprisingly satisfactory despite its great age, due to the fact that the whole structure was covered with plaster, like the majority of reinforced concrete structures designed at that time.
This research establishes that reinforced concrete structures from 1880 to 1914 differ from later reinforced concrete structures. Taking into consideration the features of early reinforced concrete structures will contribute to ensuring sustainable conservation with limited intervention, thus preserving as much as possible of the original structure when restoration work is undertaken. Working on existing buildings often requires a multidisciplinary and holistic approach. The present study could thus be extended in various areas. For example, other structural aspects could be studied more in depth, such as demonstration of the shear strength of the Hennebique system or detailed consideration of the reinforcements (low adherence, particular anchorage devices, etc.)/
C'est dans le cadre de la conservation, au sens large du terme, que s'inscrit cette recherche sur les constructions en béton armé de première génération, c'est-à-dire de la fin du 19ème siècle au début du 20ème siècle. Cette recherche traite uniquement des superstructures, à l'exclusion des fondations, routes, tuyaux, etc. et en béton armé au sens moderne du terme, c'est-à-dire un béton réalisé à base de ciment artificiel et dont les armatures interviennent surtout pour reprendre les efforts de traction, ce qui exclut par exemple les utilisations de poutrelles métalliques enrobées de béton. Certains de ces ouvrages, réalisés entre 1880 et 1914, font aujourd'hui partie intégrante du patrimoine bâti, pour leurs valeurs architecturale, historique, technique ou aussi socio-économique. Ils jalonnent désormais l'histoire de la construction comme témoins d'une époque où le béton armé était un matériau nouveau. La Première Guerre mondiale marque la fin de cette période de premières innovations, d'explorations et d'expérimentations. Elle entérine l'acceptation et la diffusion du béton armé comme matériau de construction à part entière. Cependant, ainsi que le montrent certains projets de restauration actuels aux interventions inadéquates, il y a encore une méconnaissance des spécificités du béton armé de cette époque. Les causes de leurs dégradations mal diagnostiquées sont traitées de façon inappropriée. Or, dans les prochaines années, nombre de structures en béton armé construites dans la première moitié du 20ème siècle seront amenées à subir une rénovation suite au vieillissement naturel du matériau. C'est pourquoi pour conserver au mieux ces structures, il est indispensable d'étudier en détails leurs caractéristiques techniques pour ensuite intervenir, si nécessaire, de façon précise et adaptée.
Ce doctorat s'attèle donc à identifier les particularités des constructions en béton armé construites avant l'avènement de la Première Guerre mondiale, et plus spécifiquement à étudier leurs aspects structuraux. Plusieurs axes de recherche ont été développés et ont abouti aux principaux résultats suivants.
- Basé sur le cas de la région de Bruxelles-Capitale (Belgique), un inventaire des interventions en béton armé, construites avant 1914, a été dressé pour replacer le matériau dans son contexte historique et géographique. Cette base de données, comprenant 507 biens jusqu'à présent, illustre les types d'utilisation du béton armé dans la construction au début du 20ème siècle, d'abord des fondations ou simples planchers, jusqu'à une structure monolithique complète dès la fin des années 1890. Cet inventaire est complété par le relevé détaillé des brevets, au nombre de 605, déposés à ce sujet en Belgique avant la Première Guerre mondiale. Les brevets ont joué un rôle fondamental dans le développement du béton armé. Celui-ci était, en effet, régi par un foisonnement de systèmes commerciaux, majoritairement brevetés. L'introduction du béton armé a transformé en profondeur le secteur de la construction et notamment les professions liées tant à la phase de conception qu'au chantier lui-même. Du point de vue de l'histoire de la construction, toutes ces mutations font de l'avènement du béton armé une période historique riche.
- A la lecture du panorama offert par les inventaires des constructions et des brevets, la prééminence de la compagnie du Français François Hennebique, et donc de son système, sur le marché bruxellois (et par extrapolation sur le marché belge) du béton armé avant 1914 est indéniable. La réussite commerciale de Hennebique résulte d'une combinaison de facteurs: un système efficace sur le plan structural, une qualité d'exécution de béton coulé en place fiable et méticuleuse ainsi qu'un sens développé des affaires, en maîtrisant l'art de la promotion et de la publicité notamment. Le système bien connu de Hennebique comprend un ensemble monolithique formé par des dalles (hourdis), poutres et colonnes. Ce système a, en réalité, évolué dans le temps, pas tant d'un point de vue théorique (les calculs de dimensionnement sont les mêmes) mais plutôt pratique (positionnement, type d'armatures, etc.). Cette évolution a été observée par l'étude d'une trentaine de cas pratiques exécutés par Hennebique entre 1900 et 1930 en Belgique.
- Après les entrepreneurs, qui ont été les premiers à croire aux nouvelles possibilités constructives qu'offre le béton armé ainsi qu'à son succès commercial, les ingénieurs en inventent les principes de calcul et les architectes en révolutionnent les formes. L'ingénieur belge Paul Christophe fut parmi les premiers théoriciens du béton armé. La publication de son ouvrage Le béton armé et ses applications en 1899 constitue une étape importante, et internationalement reconnue, pour le dimensionnement rationnel d'éléments structuraux en béton armé. Jusqu'à la présente recherche, sa vie et son œuvre étaient restées assez confidentielles mais la découverte d'une partie de ses archives personnelles a permis de clarifier son rôle dans la diffusion, surtout théorique, du béton armé.
- Les structures en béton armé d'avant la Première Guerre mondiale furent d'abord gouvernées par des méthodes empiriques de dimensionnement (et d'exécution) développées par chaque constructeur. L'apparition des premières règlementations entre 1904 et 1923, basées sur une analyse en contraintes admissibles et la théorie du coefficient d'équivalence, remplace ensuite peu-à-peu l'utilité des systèmes brevetés. Les différentes approches théoriques sont brièvement décrites dans cette recherche. Maitriser les hypothèses et les méthodes de calculs employées à l'époque est, en effet, une première étape pour comprendre le fonctionnement structural prévu et les potentielles défaillances de dimensionnement.
- A travers une lecture attentive de la littérature publiée à cette période, les matériaux intervenants dans la fabrication du béton armé (c'est-à-dire le béton et les armatures) et utilisés couramment au début du 20ème siècle ont été identifiés ainsi que les moyens disponibles à cette époque pour produire des structures en béton armé. Des méthodes d'essais non-destructives et destructives ont été appliquées principalement, sur le viaduc Colo-Hugues (1904, Braine-l'Alleud, système Hennebique) afin d'évaluer les caractéristiques mécaniques, les propriétés chimiques et la durabilité tant du béton que des renforcements métalliques. Comparer les résultats de ces différentes méthodes permet d'aborder les limites d'utilisation de ces techniques, lorsqu'il s'agit d'évaluer structuralement des bétons armés de première génération.
- Grâce à la compréhension des principes, semi-empiriques, de dimensionnement appliqués par le bureau Hennebique en son temps mais surtout grâce aux observations déduites des essais expérimentaux réalisés sur des poutres de grandeur réelle, prélevées sur le viaduc Colo-Hugues, le fonctionnement structural réel du système Hennebique est évalué. Comprendre et modéliser le comportement du nouveau matériau composite fut une problématique fondamentale pour accroître l'usage du béton armé au début du 20ème siècle. Actuellement, il s'agit de réévaluer le comportement de ces structures. Trois essais jusqu'à rupture ont été menés, au département BATir de l'Université libre de Bruxelles, sur des poutres à gousset en T provenant du viaduc Colo-Hugues en conditions isostatiques et soumises à flexion. Ce viaduc des chemins de fer vicinaux est un cas d'étude représentatif de la majorité des constructions Hennebique, car la poutre de section en T est la structure typique du système Hennebique, utilisée tant dans les ouvrages d'art que dans les bâtiments. Le premier essai est une flexion 4 points sur une travée complète du viaduc (6 m de portée) pour obtenir la réponse en zone de moment maximum positif. La rupture ductile a eu lieu par plastification des armatures suivie d'un écrasement du béton en zone centrale, c'est-à-dire dans la zone la plus sollicitée. Deux éléments identiques de longueur de 4 m ont été essayés en flexion 3 points pour représenter le comportement sur appuis. La rupture de ces deux dernières expériences s'est produite suite à un glissement des armatures sur appuis (goussets à côté de la colonne). Il s'agit donc d'une rupture à caractère fragile. Les trois essais combinés représentent correctement la structure hyperstatique du viaduc dans son fonctionnement en service. La capacité portante réelle du système Hennebique en service et à l'état limite ultime, du moins dans un cas de chargement, a pu être expliquée. Ces essais fournissent les données essentielles pour estimer l'efficacité structurale du système Hennebique et identifier ses faiblesses. Deux solutions de renforcement sont proposées en complément d'information.
- Les pathologies observées dans les bétons armés datant du début du 20ème siècle (nids de graviers, corrosion des armatures, etc.) sont, la plupart du temps, causées par les outils sommaires à la disposition des constructeurs (vibration à la main, rapport eau/ciment plus élevé qu'aujourd'hui, etc.) et par une connaissance limitée des phénomènes physiques et chimiques, surtout à long terme. En fait, la qualité du béton du viaduc Colo-Hugues est particulièrement satisfaisante malgré l'âge avancé du béton, grâce notamment à l'enduit recouvrant l'ensemble du viaduc, ce qui est le cas pour la majorité des structures de la période étudiée.
Cette recherche démontre que les constructions en béton armé datant de 1880 à 1914 diffèrent des ouvrages postérieurs en béton armé et qu'il serait utile pour leur restauration de tenir compte de ces spécificités. La connaissance approfondie des particularités des constructions en béton armé de première génération permettra, espérons-le, de contribuer à leur longévité en intervenant le moins possible sur les structures d'origine. Etant donné que l'étude des structures existantes nécessite le plus souvent une approche pluridisciplinaire, ce travail pourrait être poursuivi dans plusieurs domaines variés. Il resterait notamment à approfondir d'autres aspects de stabilité, comme par exemple la démonstration de l'efficacité à l'effort tranchant du système Hennebique ou encore la prise en considération plus détaillée des armatures (adhérence limitée, forme d'ancrage particulier, etc.).
Doctorat en Sciences de l'ingénieur
info:eu-repo/semantics/nonPublished
Rolin, Raphaël. "Contribution à une démarche numérique intégrée pour la préservation des patrimoines bâtis." Thesis, Compiègne, 2018. http://www.theses.fr/2018COMP2450/document.
Throughout this work, the main objective is to validate the relevance of construction and use of geometric or parametric 3D models BIM or hBlM-oriented for numerical analyzes. These include structural studies in the case of historic buildings, as well as planning for restoration work, energy renovation and rehabilitation. Complementary data mining and use of point clouds for the detection, segmentation and extraction of geometric features have also been integrated into the work and proposed methodology. The process of data processing, geometric or parametric modeling and their exploitation, proposed in this work, contributes to improve and understand better the constraints and stakes of the different configurations and conditions related to the case studies and the specific constraints specific to the types of constructions. The contributions proposed for the different geometric and parametric modeling methods from point clouds are addressed by the construction of geometric models BIM or hBlM-oriented. Similarly, the process of surface detection, extraction of data and elements from point clouds are presented. The application of these modeling methods is systematically illustrated by different case studies, all of whose relative work has been carried out within the framework of this thesis. The goal is therefore to demonstrate the interest and relevance of these numerical methods according to the context, needs and studies envisaged, for example with the spire of the Senlis cathedral (Oise) and the Hermitage site (Oise). Numerical analyzes with finite element method are used to validate the relevance of these approaches
Huang, Lei. "L'abbatiale Sainte-Foy de Conques (XIe - XIIe siècles)." Thesis, Paris 1, 2018. http://www.theses.fr/2018PA01H052.
This archaeological study of the building of the abbey church of Sainte-Foy in Conques, which is mainly focused on facing stones, has a double objective: on the one hand, to discern, as much as possible, material indications likely to enlighten the progress of construction work; on the other hand, to understand technical and economic dimensions and, more generally, the site organisation of this major Romanesque building project. Archaeological data, such as masonry discontinuities, distribution of different petrographic types, stone-cutting techniques, masons’ marks and putlog holes, make it possible to propose a construction phasing, which offers an independent and efficient framework for study of the sculpture of Sainte-Foy. The sculpture evolution is thus traced, through a global stylistic approach. Artistic transfers between Conques, Santiago de Compostela and Auvergne have also been better defined, which leads to reconsider the chronology of Romanesque churches of Auvergne, especially as Conques and Auvergne were located in the same technical geography during the second half of the eleventh century