Letteratura scientifica selezionata sul tema "Terre excavée"

El alfar de terra sigillata de Villarroya de la Sierra (Zaragoza) es conocido desde 1987, año en que se comenzó a excavar. Tras nueve campañas arqueológicas, sabemos muy bien cómo son los hornos, las producciones cerámicas, los moldes, e incluso hemos encontrado la necrópolis de los propietarios de este centro de producción. En 1999 hemos empezado a conocer su residencia, una lujosa mansión que ocupa 30.000 m con baños y pintura mural, todo lo cual indica que esta fue la villa de una poderosa familia romana, cuyo momento de esplendor fue desde mediados del siglo I d.C. al siglo III d.C., aunque el alfar siguió produciendo hasta el siglo IV d.C.

Vitex doniana Sweet est une espèce à usages multiples d’une grande importance socio-économique et commune en Afrique tropicale. Malgré sa forte utilisation en mi- lieu rural, elle est encore présente à l’état sauvage. Il existe peu de données sur sa domestication. La propagation de cet arbre par bouturage de segments de racine consti- tue une alternative à sa difficile régénéra- tion sexuée. L’objectif de notre travail était d’évaluer deux des facteurs clés (substrat d’enracinement, diamètre des boutures) qui influencent l’aptitude des boutures de segments de racine (BSR) à néoformer des pousses feuillées et des racines. Le système racinaire de 23 arbres a été partiellement excavé sur une profondeur de 20 cm. Des BSR de 15 cm de long ont été disposées hori- zontalement dans des polypropagateurs sur cinq substrats différents, arrosés matin et soir. Le dispositif était un split-plot à trois ré- pétitions. Le traitement principal recouvrait cinq substrats : terre noire (Tn), sable fin (S), sciure de bois (Sc), 50 % Tn/50 % Sc (Tn- Sc) et 50 % Tn/50 % S (Tn-S). Le traitement secondaire distinguait deux classes de dia- mètre (0,5-1cm ; 1,1-2,5 cm). Après la mise en culture des BSR, le temps de latence d’émer- gence était de 8 semaines pour les pousses aériennes et 12 pour les racines. Après 28 semaines, le pourcentage de pousses feuil- lées formées variait de 28 % (Tn) à 55 % (S). Les pousses aériennes se sont développées majoritairement (82 %) sur le pôle distal. Le diamètre des BSR a déterminé le déve- loppement des pousses feuillées (P < 0,01). Le taux de bourgeonnement des BSR oscil- lait entre 21,0 ± 1,8 % pour les BSR de 0,5- 1 cm et 86,0 ± 7,8 % pour la classe 1,1-2,5 cm. Le diamètre a également impacté l’enracine- ment des BSR (P < 0,001). Le taux d’enraci- nement des BSR variait de 12,0 ± 2,3 % pour les petits diamètres à 59,3 ± 4,7 % pour les plus gros. La multiplication végétative par BSR peut améliorer la filière économique de V. doniana dans les hautes savanes gui- néennes du Cameroun.

In 1935 M. E. L. Mallowan was rightly considered to be one of the outstanding British archaeologists of his generation. Having served his apprenticeship under Sir Leonard Woolley at Ur and supervised the prehistoric sounding at Nineveh under R. Campbell Thompson, he had then directed a successful excavation of his own at Arpachiyah (McCall 2001: 41–4), followed by the immediate publication of the final report (Mallowan/Cruikshank 1935).As a result of a change in the Iraq Antiquities Law, the division of antiquities found during excavations ceased. Mallowan, like many other archaeologists whose fieldwork had been sponsored by museums, was obliged to abandon Iraq and look for new opportunities of research in neighbouring eastern Syria, which was virtually terra incognita at this time (Oates/Oates 2001: 121). No doubt, Mallowan's interest in this area has been stimulated by the discoveries of Max von Oppenheim at Tell Halaf, where pottery has been found similar to that excavated by Mallowan at Arpachiyah. Furthermore, in 1934 Poidebard's aerial survey was published, and it included photographs of numerous archaeological sites along the Khabur and its tributaries (Mallowan 1947: 1). In the fall of 1934 Mallowan, accompanied by his wife, Agatha Christie, and an architect, Mr R. H. Macartney, arrived in Syria to inspect a number of sites located along the Khabur and Jaghjagh rivers, as well as in the Khabur plain. After a winter spent in Egypt, Mallowan returned to the Khabur area in the Spring of 1935, not only to continue his survey, but first to excavate Tell Chagar Bazar. Sherds of the same so-called Halaf pottery had been found at the base of the mound, pointing to the possibility of obtaining at this site a long stratigraphical sequence, which would, in turn, serve as a chronological framework for research on other sites (Mallowan 1936: 7–11, Fig. 2). The season's work, however, was not limited to Tell Chagar Bazar. Small teams were detached from the main force for a few days to make trial soundings on some other principal sites, such as Tell Ailun and Tell Mozan (Oates/Oates 2001: 129).

El objetivo principal de esta investigación es contribuir al debate sobre la calidad de la educación mexicana, en particular en lo que respecta a lectura en tercero de primaria. Para ello se presenta un análisis de dos evaluaciones dirigidas a esa temática en el mismo nivel educativo: el Examen para la Calidad y el Logro Educativos (EXCALE) y el Tercer Estudio Regional Comparativo y Explicativo (TERCE) en términos de su enfoque, metodología y forma de comunicación de resultados. La comparación permite abonar al discurso sobre el proceso metodológico de la evaluación a gran escala, la forma en que los resultados se comunican con el fin de ser un insumo relevante para la toma de decisiones en términos de política educativa, así como sobre el dinamismo inherente al concepto de calidad educativa que se utiliza en los procesos de evaluación.

Introduction One of the ways in which ‘country’ is made to work discursively is in ‘country music’ – defining a genre and sensibility in music production, marketing and consumption. This article seeks to excavate one small niche in the historical geography of country music to explore exactly how discursive antecedents emerged, and crucially, how images associated with ‘country’ surfaced and travelled internationally via one of the new ‘global’ media of the first half of the twentieth century – sheet music. My central arguments are twofold: first, that alongside aural qualities and lyrical content, the visual elements of sheet music were important and thus far have been under-acknowledged. Sheet music diffused the imagery connecting ‘country’ to music, to particular landscapes, and masculinities. In the literature on country music much emphasis has been placed on film, radio and television (Tichi; Peterson). Yet, sheet music was for several decades the most common way people bought personal copies of songs they liked and intended to play at home on piano, guitar or ukulele. This was particularly the case in Australia – geographically distant, and rarely included in international tours by American country music stars. Sheet music is thus a rich text to reveal the historical contours of ‘country’. My second and related argument is that that the possibilities for the globalising of ‘country’ were first explored in music. The idea of transnational discourses associated with ‘country’ and ‘rurality’ is relatively new (Cloke et al; Gorman-Murray et al; McCarthy), but in music we see early evidence of a globalising discourse of ‘country’ well ahead of the time period usually analysed. Accordingly, my focus is on the sheet music of country songs in Australia in the first half of the twentieth century and on how visual representations hybridised travelling themes to create a new vernacular ‘country’ in Australia. Creating ‘Country’ Music Country music, as its name suggests, is perceived as the music of rural areas, “defined in contrast to metropolitan norms” (Smith 301). However, the ‘naturalness’ of associations between country music and rurality belies a history of urban capitalism and the refinement of deliberate methods of marketing music through associated visual imagery. Early groups wore suits and dressed for urban audiences – but then altered appearances later, on the insistence of urban record companies, to emphasise rurality and cowboy heritage. Post-1950, ‘country’ came to replace ‘folk’ music as a marketing label, as the latter was considered to have too many communistic references (Hemphill 5), and the ethnic mixing of earlier folk styles was conveniently forgotten in the marketing of ‘country’ music as distinct from African American ‘race’ and ‘r and b’ music. Now an industry of its own with multinational headquarters in Nashville, country music is a ‘cash cow’ for entertainment corporations, with lower average production costs, considerable profit margins, and marketing advantages that stem from tropes of working class identity and ‘rural’ honesty (see Lewis; Arango). Another of country music’s associations is with American geography – and an imagined heartland in the colonial frontier of the American West. Slippages between ‘country’ and ‘western’ in music, film and dress enhance this. But historical fictions are masked: ‘purists’ argue that western dress and music have nothing to do with ‘country’ (see truewesternmusic.com), while recognition of the Spanish-Mexican, Native American and Hawaiian origins of ‘cowboy’ mythology is meagre (George-Warren and Freedman). Similarly, the highly international diffusion and adaptation of country music as it rose to prominence in the 1940s is frequently downplayed (Connell and Gibson), as are the destructive elements of colonialism and dispossession of indigenous peoples in frontier America (though Johnny Cash’s 1964 album The Ballads Of The American Indian: Bitter Tears was an exception). Adding to the above is the way ‘country’ operates discursively in music as a means to construct particular masculinities. Again, linked to rural imagery and the American frontier, the dominant masculinity is of rugged men wrestling nature, negotiating hardships and the pressures of family life. Country music valorises ‘heroic masculinities’ (Holt and Thompson), with echoes of earlier cowboy identities reverberating into contemporary performance through dress style, lyrical content and marketing imagery. The men of country music mythology live an isolated existence, working hard to earn an income for dependent families. Their music speaks to the triumph of hard work, honest values (meaning in this context a musical style, and lyrical concerns that are ‘down to earth’, ‘straightforward’ and ‘without pretence’) and physical strength, in spite of neglect from national governments and uncaring urban leaders. Country music has often come to be associated with conservative politics, heteronormativity, and whiteness (Gibson and Davidson), echoing the wider politics of ‘country’ – it is no coincidence, for example, that the slogan for the 2008 Republican National Convention in America was ‘country first’. And yet, throughout its history, country music has also enabled more diverse gender performances to emerge – from those emphasising (or bemoaning) domesticity; assertive femininity; creative negotiation of ‘country’ norms by gay men; and ‘alternative’ culture (captured in the marketing tag, ‘alt.country’); to those acknowledging white male victimhood, criminality (‘the outlaw’), vulnerability and cruelty (see Johnson; McCusker and Pecknold; Saucier). Despite dominant tropes of ‘honesty’, country music is far from transparent, standing for certain values and identities, and yet enabling the construction of diverse and contradictory others. Historical analysis is therefore required to trace the emergence of ‘country’ in music, as it travelled beyond America. A Note on Sheet Music as Media Source Sheet music was one of the main modes of distribution of music from the 1930s through to the 1950s – a formative period in which an eclectic group of otherwise distinct ‘hillbilly’ and ‘folk’ styles moved into a single genre identity, and after which vinyl singles and LP records with picture covers dominated. Sheet music was prevalent in everyday life: beyond radio, a hit song was one that was widely purchased as sheet music, while pianos and sheet music collections (stored in a piece of furniture called a ‘music canterbury’) in family homes were commonplace. Sheet music is in many respects preferable to recorded music as a form of evidence for historical analysis of country music. Picture LP covers did not arrive until the late 1950s (by which time rock and roll had surpassed country music). Until then, 78 rpm shellac discs, the main form of pre-recorded music, featured generic brown paper sleeves from the individual record companies, or city retail stores. Also, while radio was clearly central to the consumption of music in this period, it obviously also lacked the pictorial element that sheet music could provide. Sheet music bridged the music and printing industries – the latter already well-equipped with colour printing, graphic design and marketing tools. Sheet music was often literally crammed with information, providing the researcher with musical notation, lyrics, cover art and embedded advertisements – aural and visual texts combined. These multiple dimensions of sheet music proved useful here, for clues to the context of the music/media industries and geography of distribution (for instance, in addresses for publishers and sheet music retail shops). Moreover, most sheet music of the time used rich, sometimes exaggerated, images to convince passing shoppers to buy songs that they had possibly never heard. As sheet music required caricature rather than detail or historical accuracy, it enabled fantasy without distraction. In terms of representations of ‘country’, then, sheet music is perhaps even more evocative than film or television. Hundreds of sheet music items were collected for this research over several years, through deliberate searching (for instance, in library archives and specialist sheet music stores) and with some serendipity (for instance, when buying second hand sheet music in charity shops or garage sales). The collected material is probably not representative of all music available at the time – it is as much a specialised personal collection as a comprehensive survey. However, at least some material from all the major Australian country music performers of the time were found, and the resulting collection appears to be several times larger than that held currently by the National Library of Australia (from which some entries were sourced). All examples here are of songs written by, or cover art designed for Australian country music performers. For brevity’s sake, the following analysis of the sheet music follows a crudely chronological framework. Country Music in Australia Before ‘Country’ Country music did not ‘arrive’ in Australia from America as a fully-finished genre category; nor was Australia at the time without rural mythology or its own folk music traditions. Associations between Australian national identity, rurality and popular culture were entrenched in a period of intense creativity and renewed national pride in the decades prior to and after Federation in 1901. This period saw an outpouring of art, poetry, music and writing in new nationalist idiom, rooted in ‘the bush’ (though drawing heavily on Celtic expressions), and celebrating themes of mateship, rural adversity and ‘battlers’. By the turn of the twentieth century, such myths, invoked through memory and nostalgia, had already been popularised. Australia had a fully-established system of colonies, capital cities and state governments, and was highly urbanised. Yet the poetry, folk music and art, invariably set in rural locales, looked back to the early 1800s, romanticising bush characters and frontier events. The ‘bush ballad’ was a central and recurring motif, one that commentators have argued was distinctly, and essentially ‘Australian’ (Watson; Smith). Sheet music from this early period reflects the nationalistic, bush-orientated popular culture of the time: iconic Australian fauna and flora are prominent, and Australian folk culture is emphasised as ‘native’ (being the first era of cultural expressions from Australian-born residents). Pioneer life and achievements are celebrated. ‘Along the road to Gundagai’, for instance, was about an iconic Australian country town and depicted sheep droving along rustic trails with overhanging eucalypts. Male figures are either absent, or are depicted in situ as lone drovers in the archetypal ‘shepherd’ image, behind their flocks of sheep (Figure 1). Figure 1: No. 1 Magpie Ballads – The Pioneer (c1900) and Along the road to Gundagai (1923). Further colonial ruralities developed in Australia from the 1910s to 1940s, when agrarian values grew in the promotion of Australian agricultural exports. Australia ‘rode on the sheep’s back’ to industrialisation, and governments promoted rural development and inland migration. It was a period in which rural lifestyles were seen as superior to those in the crowded inner city, and government strategies sought to create a landed proletariat through post-war land settlement and farm allotment schemes. National security was said to rely on populating the inland with those of European descent, developing rural industries, and breeding a healthier and yet compliant population (Dufty), from which armies of war-ready men could be recruited in times of conflict. Popular culture served these national interests, and thus during these decades, when ‘hillbilly’ and other North American music forms were imported, they were transformed, adapted and reworked (as in other places such as Canada – see Lehr). There were definite parallels in the frontier narratives of the United States (Whiteoak), and several local adaptations followed: Tex Morton became Australia’s ‘Yodelling boundary rider’ and Gordon Parsons became ‘Australia’s yodelling bushman’. American songs were re-recorded and performed, and new original songs written with Australian lyrics, titles and themes. Visual imagery in sheet music built upon earlier folk/bush frontier themes to re-cast Australian pastoralism in a more settled, modernist and nationalist aesthetic; farms were places for the production of a robust nation. Where male figures were present on sheet music covers in the early twentieth century, they became more prominent in this period, and wore Akubras (Figure 2). The lyrics to John Ashe’s Growin’ the Golden Fleece (1952) exemplify this mix of Australian frontier imagery, new pastoralist/nationalist rhetoric, and the importation of American cowboy masculinity: Go west and take up sheep, man, North Queensland is the shot But if you don’t get rich, man, you’re sure to get dry rot Oh! Growin’ the golden fleece, battlin’ a-way out west Is bound to break your flamin’ heart, or else expand your chest… We westerners are handy, we can’t afford to crack Not while the whole darn’d country is riding on our back Figure 2: Eric Tutin’s Shearers’ Jamboree (1946). As in America, country music struck a chord because it emerged “at a point in history when the project of the creation and settlement of a new society was underway but had been neither completed nor abandoned” (Dyer 33). Governments pressed on with the colonial project of inland expansion in Australia, despite the theft of indigenous country this entailed, and popular culture such as music became a means to normalise and naturalise the process. Again, mutations of American western imagery, and particular iconic male figures were important, as in Roy Darling’s (1945) Overlander Trail (Figure 3): Wagon wheels are rolling on, and the days seem mighty long Clouds of heat-dust in the air, bawling cattle everywhere They’re on the overlander trail Where only sheer determination will prevail Men of Aussie with a job to do, they’ll stick and drive the cattle through And though they sweat they know they surely must Keep on the trail that winds a-head thro’ heat and dust All sons of Aussie and they will not fail. Sheet music depicted silhouetted men in cowboy hats on horses (either riding solo or in small groups), riding into sunsets or before looming mountain ranges. Music – an important part of popular culture in the 1940s – furthered the colonial project of invading, securing and transforming the Australian interior by normalising its agendas and providing it with heroic male characters, stirring tales and catchy tunes. Figure 3: ‘Roy Darling’s (1945) Overlander Trail and Smoky Dawson’s The Overlander’s Song (1946). ‘Country Music’ Becomes a (Globalised) Genre Further growth in Australian country music followed waves of popularity in the United States in the 1940s and 1950s, and was heavily influenced by new cross-media publicity opportunities. Radio shows expanded, and western TV shows such as Bonanza and On the Range fuelled a ‘golden age’. Australian performers such as Slim Dusty and Smokey Dawson rose to fame (see Fitzgerald and Hayward) in an era when rural-urban migration peaked. Sheet music reflected the further diffusion and adoption of American visual imagery: where male figures were present on sheet music covers, they became more prominent than before and wore Stetsons. Some were depicted as chiselled-faced but simple men, with plain clothing and square jaws. Others began to more enthusiastically embrace cowboy looks, with bandana neckerchiefs, rawhide waistcoats, embellished and harnessed tall shaft boots, pipe-edged western shirts with wide collars, smile pockets, snap fasteners and shotgun cuffs, and fringed leather jackets (Figure 4). Landscapes altered further too: cacti replaced eucalypts, and iconic ‘western’ imagery of dusty towns, deserts, mesas and buttes appeared (Figure 5). Any semblance of folk music’s appeal to rustic authenticity was jettisoned in favour of showmanship, as cowboy personas were constructed to maximise cinematic appeal. Figure 4: Al Dexter’s Pistol Packin’ Mama (1943) and Reg Lindsay’s (1954) Country and Western Song Album. Figure 5: Tim McNamara’s Hitching Post (1948) and Smoky Dawson’s Golden West Album (1951). Far from slavish mimicry of American culture, however, hybridisations were common. According to Australian music historian Graeme Smith (300): “Australian place names appear, seeking the same mythological resonance that American localisation evoked: hobos became bagmen […] cowboys become boundary riders.” Thus alongside reproductions of the musical notations of American songs by Lefty Frizzel, Roy Carter and Jimmie Rodgers were songs with localised themes by new Australian stars such as Reg Lindsay and Smoky Dawson: My curlyheaded buckaroo, My home way out back, and On the Murray Valley. On the cover of The square dance by the billabong (Figure 6) – the title of which itself was a conjunction of archetypal ‘country’ images from both America and Australia – a background of eucalypts and windmills frames dancers in classic 1940s western (American) garb. In the case of Tex Morton’s Beautiful Queensland (Figure 7), itself mutated from W. Lee O’Daniel’s Beautiful Texas (c1945), the sheet music instructed those playing the music that the ‘names of other states may be substituted for Queensland’. ‘Country’ music had become an established genre, with normative values, standardised images and themes and yet constituted a stylistic formula with enough polysemy to enable local adaptations and variations. Figure 6: The Square dance by the billabong, Vernon Lisle, 1951. Figure 7: Beautiful Queensland, Tex Morton, c1945 source: http://nla.gov.au/nla.mus-vn1793930. Conclusions In country music images of place and masculinity combine. In music, frontier landscapes are populated by rugged men living ‘on the range’ in neo-colonial attempts to tame the land and convert it to productive uses. This article has considered only one media – sheet music – in only one country (Australia) and in only one time period (1900-1950s). There is much more to say than was possible here about country music, place and gender – particularly recently, since ‘country’ has fragmented into several niches, and marketing of country music via cable television and the internet has ensued (see McCusker and Pecknold). My purpose here has been instead to explore the early origins of ‘country’ mythology in popular culture, through a media source rarely analysed. Images associated with ‘country’ travelled internationally via sheet music, immensely popular in the 1930s and 1940s before the advent of television. The visual elements of sheet music contributed to the popularisation and standardisation of genre expectations and appearances, and yet these too travelled and were adapted and varied in places like Australia which had their own colonial histories and folk music heritages. Evidenced here is how combinations of geographical and gender imagery embraced imported American cowboy imagery and adapted it to local markets and concerns. Australia saw itself as a modern rural utopia with export aspirations and a desire to secure permanence through taming and populating its inland. Sheet music reflected all this. So too, sheet music reveals the historical contours of ‘country’ as a transnational discourse – and the extent to which ‘country’ brought with it a clearly defined set of normative values, a somewhat exaggerated cowboy masculinity, and a remarkable capacity to be moulded to local circumstances. Well before later and more supposedly ‘global’ media such as the internet and television, the humble printed sheet of notated music was steadily shaping ‘country’ imagery, and an emergent international geography of cultural flows. References Arango, Tim. “Cashville USA.” Fortune, Jan 29, 2007. Sept 3, 2008, http://money.cnn.com/magazines/fortune/fortune_archive/2007/01/22/8397980/index.htm. Cloke, Paul, Marsden, Terry and Mooney, Patrick, eds. Handbook of Rural Studies, London: Sage, 2006. Connell, John and Gibson, Chris. Sound Tracks: Popular Music, Identity and Place, London: Routledge, 2003. Dufty, Rae. Rethinking the politics of distribution: the geographies and governmentalities of housing assistance in rural New South Wales, Australia, PhD thesis, UNSW, 2008. Dyer, Richard. White: Essays on Race and Culture, London: Routledge, 1997. George-Warren, Holly and Freedman, Michelle. How the West was Worn: a History of Western Wear, New York: Abrams, 2000. Fitzgerald, Jon and Hayward, Phil. “At the confluence: Slim Dusty and Australian country music.” Outback and Urban: Australian Country Music. Ed. Phil Hayward. Gympie: Australian Institute of Country Music Press, 2003. 29-54. Gibson, Chris and Davidson, Deborah. “Tamworth, Australia’s ‘country music capital’: place marketing, rural narratives and resident reactions.” Journal of Rural Studies 20 (2004): 387-404. Gorman-Murray, Andrew, Darian-Smith, Kate and Gibson, Chris. “Scaling the rural: reflections on rural cultural studies.” Australian Humanities Review 45 (2008): in press. Hemphill, Paul. The Nashville Sound: Bright Lights and Country Music, New York: Simon and Schuster, 1970. Holt, Douglas B. and Thompson, Craig J. “Man-of-action heroes: the pursuit of heroic masculinity in everyday consumption.” Journal of Consumer Research 31 (2004). Johnson, Corey W. “‘The first step is the two-step’: hegemonic masculinity and dancing in a country western gay bar.” International Journal of Qualitative Studies in Education 18 (2004): 445-464. Lehr, John C. “‘Texas (When I die)’: national identity and images of place in Canadian country music broadcasts.” The Canadian Geographer 27 (1983): 361-370. Lewis, George H. “Lap dancer or hillbilly deluxe? The cultural construction of modern country music.” Journal of Popular Culture, 31 (1997): 163-173. 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L’impression 3D du béton est l'une des technologies de construction les plus récentes. Elle offre des avantages et des opportunités par rapport à la méthode de construction traditionnelle, notamment la rapidité de la construction et la flexibilité de la conception architecturale. Cependant, la plupart des encres imprimables utilisées à ce jour nécessitent une forte teneur en ciment, dont la production génère de fortes émissions de CO2. La réduction de l'impact environnemental du béton imprimable est actuellement au centre des préoccupations des chercheurs qui visent à utiliser des matériaux alternatifs pour remplacer le ciment et réduire sa forte consommation dans les mélanges imprimables en 3D. Ces travaux de recherche portent sur la valorisation de matériaux alternatifs et innovants, actuellement considérés comme des déchets, dans l'impression 3D, afin de développer des mélanges imprimables à faible impact environnemental. Les matériaux alternatifs utilisés sont les sédiments de dragage, les poudres de fibres de verre polyester et la terre excavée. Ces matériaux sont choisis pour leur potentiel de valorisation, leurs propriétés intrinsèques et pour la nécessité urgente de les gérer en raison de leur grande quantité. Par ailleurs, peu de travaux sont consacrés à la valorisation de ces types de matériaux dans l'impression 3D du béton, d’où l’objectif de cette thèse. Une méthodologie expérimentale est ainsi mise en œuvre pour développer des mélanges optimaux. Tout d'abord, l'extrudabilité et la buildabilité sont évaluées et vérifiées afin de valider l’imprimabilité des mélanges développés. Ensuite, les propriétés à l’état frais et durci des mortiers imprimables sont étudiées. De plus, dans ces travaux, différentes échelles d'impression sont testées, depuis l'échelle du laboratoire jusqu’à celle d'une imprimante 3D. Dans la première partie de l’étude, le sédiment flash calciné est utilisé dans une formulation témoin imprimable, produisant un liant binaire (ciment/sédiment flash calciné) et un liant ternaire (ciment/sédiment flash calciné/filler calcaire), et les poudres de fibres de verre polyester sont utilisées, en tant que renfort, dans la formulation témoin, substituant une partie du sable. Dans la deuxième partie de l’étude, la terre est utilisée en tant que substitut total du sable. Les résultats de la première partie de l’étude montrent que plusieurs mélanges contenant du sédiment flash calciné sont imprimables. Ces mélanges contiennent 5 et 10% de sédiment lorsque le sédiment est valorisé seul, et 10 et 20% de sédiment lorsqu'il est valorisé avec 20 et 30% de filler calcaire, respectivement. Une substitution du ciment de 50% est donc atteinte avec le mélange imprimable contenant 20% de sédiment et 30% de filler calcaire. En outre, les mélanges contenant jusqu'à 10% de poudres de fibres de verre polyester sont également imprimables. D’autre part, les résultats de la deuxième partie de l’étude montrent que les formulations développées avec un taux élevé de terre excavée et une faible teneur en ciment sont imprimables et résistantes. Les formulations imprimables contiennent différentes quantités de terre, environ 2, 4 et 6 fois la quantité du ciment, la formulation la plus écologique ayant une teneur en terre de 1602 kg/m3 et une teneur en ciment de 282 kg/m3. Ces travaux de recherche mettent en évidence la possibilité de développer de nouveaux mélanges écologiques et résistants à base de matériaux de substitution, qui peuvent être utilisés dans des applications de construction par impression 3D
Concrete 3D Printing is one of the newest technologies in the field of construction. It offers advantages and opportunities over the traditional construction method, notably speed of construction and flexibility of architectural design. However, most printable materials used nowadays require a high cement content, the production of which generates significant CO2 emissions. Reducing the environmental impact of printable concrete is currently the focus of researchers who aim to use alternative materials to replace cement and reduce its high consumption in 3D printable mixes. This research work focuses on the valorization of alternative and innovative materials, currently considered as waste, in 3D printing, to develop printable mixtures with low environmental impact. The alternative materials used are dredged sediments, polyester glass-fiber powders and excavated soil. These materials are chosen for their recycling potential, their intrinsic properties, and the urgency of their management due to their large quantity. Moreover, little work is devoted to the recycling of these specific types of waste in concrete 3D printing, hence the objective of this thesis. An experimental methodology is therefore implemented to develop optimal mixtures. First, the extrudability and buildability are evaluated and verified in order to validate the printability of the developed mixes. Then, the fresh and hardened properties of the printable mortars are studied. Furthermore, in this research, different printing scales are tested, from the laboratory scale to the 3D printer scale. In the first part of the study, flash-calcined sediment is used in a printable control mixture, producing a binary binder (cement/flash-calcined sediment) and a ternary binder (cement/flash-calcined sediment/limestone filler), and polyester glass-fiber powders are used, as reinforcement, in the control mixture, substituting a portion of the sand. In the second part of the study, excavated soil is used as a total substitute for sand. The results of the first part of the study show that several mixtures containing flash-calcined sediment are printable. These mixtures contain 5 and 10% of sediment when used alone, and 10 and 20% of sediment when used with 20 and 30% of limestone filler, respectively. A cement substitution of 50% is therefore achieved with the printable mixture containing 20% of sediment and 30% of limestone filler. In addition, mixtures containing up to 10% of polyester glass-fiber powders are also printable. Furthermore, the results of the second part of the study show that formulations with a high content of excavated soil and a low cement content are printable and resistant. The printable formulations contain different amounts of soil, about 2, 4 and 6 times the amount of cement, with the most environmentally friendly formulation having a soil content of 1602 kg/m3 and a cement content of 282 kg/m3. This research work highlights the possibility of developing new ecological and resistant mixtures based on alternative materials that can be used in 3D printing construction applications