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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Desenvolvimento de uma ligação estrutural para construção com bambu guadua

Sánchez Quintero, Carlos Andrés January 2015 (has links)
Dissertação (mestrado) - Universidade Federal de Santa Catarina, Centro Tecnológico, Programa de Pós-Graduação em Arquitetura e Urbanismo, Florianópolis, 2015. / Made available in DSpace on 2016-10-19T13:15:48Z (GMT). No. of bitstreams: 1 338940.pdf: 4950721 bytes, checksum: e4fe4a16774fc9d0f8bc04bba127085b (MD5) Previous issue date: 2015 / O bambu é um material de construção com uma capacidade insuperável de renovação e propriedades mecânicas importantes para o projeto de estruturas. É também um material econômico com grande versatilidade na indústria da construção, no entanto, devido a sua forma, em sua condição natural roliça, apresenta limitações formais na configuração de estruturas e patologias pós-construção associadas com a técnica construtiva. O objetivo da pesquisa foi desenvolver uma ligação estrutural para construção com bambu Guadua, com parâmetros de baixo custo, pré-montagem, industrialização de peças e versatilidade formal. Foram desenvolvidas as peças que compõem a ligação e feita uma análise das possibilidades arquitetônicas que fornece. Depois foram feitos, na Universidade Nacional da Colômbia em Medellín, ensaios de compressão e tração em oito corpos de prova de bambu Guadua com o sistema de ligação desenvolvido. Os ensaios de resistência foram realizados para duas dimensões de terminal e em duas configurações: linear e dois elementos em cruz. A ligação atingiu valores de resistência à tração acima dos 13 kN na configuração linear e acima de 32 kN na configuração em cruz. Esses valores representam 157,3% e 187,5% respectivamente, quando comparado com os valores de esforços admissíveis fornecidos pela norma colombiana NSR-10, para estruturas de bambu Guadua. Esses valores poderiam ser maiores uma vez que no ensaio a falha apresentou-se nas barras rosqueadas de sujeição à prensa. Quando submetida à compressão, os elementos de ligação atingiram valores acima de 16 kN na configuração linear e acima de 19 kN na configuração cruzada. Isso corresponde a 240,9% e 121,2% respectivamente, dos valores de referência da norma. Por fim, foi feito o projeto de um protótipo, construindo uma parte da estrutura, utilizando o sistema de ligação desenvolvido. Assim, pode-se concluir que a ligação tem um bom desempenho estrutural, especialmente aos esforços de tração no sentido axial, pudendo ser utilizada na construção.<br> / Abstract : Bamboo is a building material that can renew it self in a unbeatable rate, and has important mechanic properties for been used on structural projects. Is ass well, a very versatile element on the building industry and a very economic material. However, its natural rounded shape restricts constructing formal possibilities and favor the appearance of pathologies associated with the building technique. The aim of the research was to develop a structural construction joint with Guadua Bamboo taking into account parameters of low cost, pre-assembly possibilities, easy implementation and formal versatility. The joint pieces were designed and developed and a formal analysis was made to determine the architectural possibilities of the element. Afterwards, there were conducted a series of tensile and compressive tests on eight sample bodies constructed whit Bamboo Guadua and the designed joint, on the Universidad Nacional de Colombia?s structures laboratory. The strength tests were applied on two joints with different sizes arranged on to configurations: linear and crossed.The joint reached tensile strength values over 13 kN for the linear configuration, and over 32 kN for the crossed one. Those values represent 157,3% and 187,5% of the Colombian NSR-10 regulation admissible strength values for Bamboo Guadua. It was observed that those values could be easily improved, because the structure failure was on the threaded bar grabbed to the press. For the compressive tests the results came above 16 kN for the linear configuration and above 19 kN for the crossed one. This represent 240,9% and 121,2% of the Colombian NSR-10 regulation admissible strength values for Bamboo Guadua.Finally a structural portion of the design prototype was build with the developed joint, by which was concluded that the element has good structural performance, especially with tensile axial forces, making it suitable for building projects.
2

Desenvolvimento de uma ligação estrutural para construção com bambu guadua

Sánchez Quintero, Carlos Andrés January 2015 (has links)
Dissertação (mestrado) - Universidade Federal de Santa Catarina, Centro Tecnológico, Programa de Pós-Graduação em Arquitetura e Urbanismo, Florianópolis, 2015. / Made available in DSpace on 2016-05-24T17:49:24Z (GMT). No. of bitstreams: 1 338940.pdf: 4950721 bytes, checksum: e4fe4a16774fc9d0f8bc04bba127085b (MD5) Previous issue date: 2015 / O bambu é um material de construção com uma capacidade insuperável de renovação e propriedades mecânicas importantes para o projeto de estruturas. à também um material econômico com grande versatilidade na indústria da construção, no entanto, devido a sua forma, em sua condição natural roliça, apresenta limitações formais na configuração de estruturas e patologias pós-construção associadas com a técnica construtiva. O objetivo da pesquisa foi desenvolver uma ligação estrutural para construção com bambu Guadua, com parâmetros de baixo custo, pré-montagem, industrialização de peças e versatilidade formal. Foram desenvolvidas as peças que compõem a ligação e feita uma análise das possibilidades arquitetônicas que fornece. Depois foram feitos, na Universidade Nacional da Colômbia em Medellín, ensaios de compressão e tração em oito corpos de prova de bambu Guadua com o sistema de ligação desenvolvido. Os ensaios de resistência foram realizados para duas dimensões de terminal e em duas configurações: linear e dois elementos em cruz. A ligação atingiu valores de resistência à tração acima dos 13 kN na configuração linear e acima de 32 kN na configuração em cruz. Esses valores representam 157,3% e 187,5% respectivamente, quando comparado com os valores de esforços admissíveis fornecidos pela norma colombiana NSR-10, para estruturas de bambu Guadua. Esses valores poderiam ser maiores uma vez que no ensaio a falha apresentou-se nas barras rosqueadas de sujeição à prensa. Quando submetida à compressão, os elementos de ligação atingiram valores acima de 16 kN na configuração linear e acima de 19 kN na configuração cruzada. Isso corresponde a 240,9% e 121,2% respectivamente, dos valores de referência da norma. Por fim, foi feito o projeto de um protótipo, construindo uma parte da estrutura, utilizando o sistema de ligação desenvolvido. Assim, pode-se concluir que a ligação tem um bom desempenho estrutural, especialmente aos esforços de tração no sentido axial, pudendo ser utilizada na construção.<br> / Abstract : Bamboo is a building material that can renew it self in a unbeatable rate, and has important mechanic properties for been used on structural projects. Is ass well, a very versatile element on the building industry and a very economic material. However, its natural rounded shape restricts constructing formal possibilities and favor the appearance of pathologies associated with the building technique. The aim of the research was to develop a structural construction joint with Guadua Bamboo taking into account parameters of low cost, pre-assembly possibilities, easy implementation and formal versatility. The joint pieces were designed and developed and a formal analysis was made to determine the architectural possibilities of the element. Afterwards, there were conducted a series of tensile and compressive tests on eight sample bodies constructed whit Bamboo Guadua and the designed joint, on the Universidad Nacional de Colombia?s structures laboratory. The strength tests were applied on two joints with different sizes arranged on to configurations: linear and crossed.The joint reached tensile strength values over 13 kN for the linear configuration, and over 32 kN for the crossed one. Those values represent 157,3% and 187,5% of the Colombian NSR-10 regulation admissible strength values for Bamboo Guadua. It was observed that those values could be easily improved, because the structure failure was on the threaded bar grabbed to the press. For the compressive tests the results came above 16 kN for the linear configuration and above 19 kN for the crossed one. This represent 240,9% and 121,2% of the Colombian NSR-10 regulation admissible strength values for Bamboo Guadua.Finally a structural portion of the design prototype was build with the developed joint, by which was concluded that the element has good structural performance, especially with tensile axial forces, making it suitable for building projects.
3

Caracterização química, física e anatômica do bambu Guadua tagoara para polpação Kraft /

Bilesky, Paulo Rossi. January 2014 (has links)
Orientador: Gustavo Ventorim / Coorientador: José Cláudio Caraschi / Banca: Ricardo Marques Barreiros / Banca: Fábio Minoru Yamaji / Resumo: Este trabalho teve como objetivo caracterizar o bambu Guadua tagoara com 1 e 3 anos de idade e o Pinus elliottii de 12 anos quanto às propriedades químicas, físicas e anatômicas; realizar a polpação Kraft e comparar as polpas celulósicas de mesmo número kappa e grau de refino quanto às propriedades físico-mecânicas do papel produzido. Foi utilizado o bambu de 3 anos para polpação Kraft, variando a temperatura e álcali ativo. Para fins de comparação, utilizou-se a polpa de pinus, escolhendo o número kappa próximo de 27 e 23 ºSR de refino para comparar as características das polpas. Para o bambu de 1 e 3 anos de idade, os teores de lignina e cinzas não apresentaram variações expressivas, entretanto, os valores de extrativos totais, holocelulose e densidade básica apresentaram diferenças. Para os extrativos, a variação é de 15,81% a 23,25%, de 1 ano para 3 anos, respectivamente e de 66,55% e 59,46% para os teores de holocelulose. O teor de lignina permaneceu inalterado com a maturidade do bambu. A densidade básica variou de 0,250 g/cm3 para 0,460 g/cm3 com a maturidade do bambu, indicando a idade de 3 anos como mais adequada para polpação. Entre as espécies de madeira e bambu, verificou-se um maior teor de cinzas e extrativos e menores teores de holocelulose e lignina no bambu. As fibras de bambu se apresentaram menores e mais estreitas do que as de pinus. A polpação do bambu obteve rendimentos entre 40,95% a 51,75% e polpas com baixo número kappa, devido ao menor teor de lignina no bambu. Para o mesmo número kappa, o rendimento do bambu foi maior do que o do pinus. A polpa celulósica de pinus apresentou melhores propriedades físico-mecânicas em todos os ensaios realizados em comparação com a polpa de bambu / Abstract: The purposes of this study were to characterize the chemical, physical and anatomical properties of 1- to 3-year-old Guadua tagoara bamboo and 12-year-old Pinus elliottii; perform Kraft pulping and compare cellulosic pulp at same kappa number and refining intensity, regarding physical and mechanical properties of manufactured paper. In order to do that, 3-year-old bamboo samples were used for Kraft pulping, varying temperature and active alkali. Slash pine pulp was used, with kappa number at around 27 and 23 ºSR to compare different pulp features. For 1- to 3-year-old bamboo, ash and lignin contents did not show any significant variation; however, total extractive content, holocellulose and specific gravity differed. Extractive content of 1- to 3-year-old specimens, ranged from 15.81% to 23.25%, respectively; holocellulose contents were 66.55% and 59.46%. Lignin contents did not change and specific gravity ranged from 0.250 g/cm3 to 0.460 g/cm3 for mature bamboo, which shows 3-year-old specimens are best suited for pulping. Bamboo specimens showed higher ash and extractive contents and lower lignin and holocellulose contents when compared with wood specimens. Bamboo fibers were shorter and finer than slash pine fibers. Bamboo pulp yield was between 40.95% and 51.75% with low kappa number due to lower lignin content in bamboo. Bamboo showed higher pulp yield when compared with slash pinus for same kappa number. Slash pine cellulosic pulp showed better physical-mechanical properties in all tests carried out when compared with bamboo pulp / Mestre
4

Caracterização química, física e anatômica do bambu Guadua tagoara para polpação Kraft / Chemical, physical and anatomical characterization of Guadua tagoara bamboo for Kraft pulping

Bilesky, Paulo Rossi [UNESP] 01 July 2014 (has links) (PDF)
Made available in DSpace on 2015-03-03T11:52:57Z (GMT). No. of bitstreams: 0 Previous issue date: 2014-07-01Bitstream added on 2015-03-03T12:06:48Z : No. of bitstreams: 1 000807326.pdf: 456690 bytes, checksum: de0bb4981d1ade946919e5b9618494dd (MD5) / Este trabalho teve como objetivo caracterizar o bambu Guadua tagoara com 1 e 3 anos de idade e o Pinus elliottii de 12 anos quanto às propriedades químicas, físicas e anatômicas; realizar a polpação Kraft e comparar as polpas celulósicas de mesmo número kappa e grau de refino quanto às propriedades físico-mecânicas do papel produzido. Foi utilizado o bambu de 3 anos para polpação Kraft, variando a temperatura e álcali ativo. Para fins de comparação, utilizou-se a polpa de pinus, escolhendo o número kappa próximo de 27 e 23 ºSR de refino para comparar as características das polpas. Para o bambu de 1 e 3 anos de idade, os teores de lignina e cinzas não apresentaram variações expressivas, entretanto, os valores de extrativos totais, holocelulose e densidade básica apresentaram diferenças. Para os extrativos, a variação é de 15,81% a 23,25%, de 1 ano para 3 anos, respectivamente e de 66,55% e 59,46% para os teores de holocelulose. O teor de lignina permaneceu inalterado com a maturidade do bambu. A densidade básica variou de 0,250 g/cm3 para 0,460 g/cm3 com a maturidade do bambu, indicando a idade de 3 anos como mais adequada para polpação. Entre as espécies de madeira e bambu, verificou-se um maior teor de cinzas e extrativos e menores teores de holocelulose e lignina no bambu. As fibras de bambu se apresentaram menores e mais estreitas do que as de pinus. A polpação do bambu obteve rendimentos entre 40,95% a 51,75% e polpas com baixo número kappa, devido ao menor teor de lignina no bambu. Para o mesmo número kappa, o rendimento do bambu foi maior do que o do pinus. A polpa celulósica de pinus apresentou melhores propriedades físico-mecânicas em todos os ensaios realizados em comparação com a polpa de bambu / The purposes of this study were to characterize the chemical, physical and anatomical properties of 1- to 3-year-old Guadua tagoara bamboo and 12-year-old Pinus elliottii; perform Kraft pulping and compare cellulosic pulp at same kappa number and refining intensity, regarding physical and mechanical properties of manufactured paper. In order to do that, 3-year-old bamboo samples were used for Kraft pulping, varying temperature and active alkali. Slash pine pulp was used, with kappa number at around 27 and 23 ºSR to compare different pulp features. For 1- to 3-year-old bamboo, ash and lignin contents did not show any significant variation; however, total extractive content, holocellulose and specific gravity differed. Extractive content of 1- to 3-year-old specimens, ranged from 15.81% to 23.25%, respectively; holocellulose contents were 66.55% and 59.46%. Lignin contents did not change and specific gravity ranged from 0.250 g/cm3 to 0.460 g/cm3 for mature bamboo, which shows 3-year-old specimens are best suited for pulping. Bamboo specimens showed higher ash and extractive contents and lower lignin and holocellulose contents when compared with wood specimens. Bamboo fibers were shorter and finer than slash pine fibers. Bamboo pulp yield was between 40.95% and 51.75% with low kappa number due to lower lignin content in bamboo. Bamboo showed higher pulp yield when compared with slash pinus for same kappa number. Slash pine cellulosic pulp showed better physical-mechanical properties in all tests carried out when compared with bamboo pulp
5

Determinación de los esfuerzos últimos de la Guadua Angustifolia en la región andina de Colombia correlacionada con variables de clima

Lozano Peña, Jorge Enrique 13 April 2021 (has links)
[ES] En el año 2010, el Reglamento colombiano de construcción sismoresistente (NSR-10) estableció el procedimiento de diseño basado en el método de los esfuerzos admisibles para utilizar la Guadua angustifolia Kunth como material de construcción. En la región Andina de Colombia hay gran presencia de bosques naturales de Guadua. Sin embargo, las condiciones geográficas y ambientales (temperatura, pluviosidad, altura sobre el nivel del mar, etc.) dificultan el aprovechamiento de este material para la construcción. Más aún, su localización se encuentra principalmente en lugares de difícil acceso, generando, además de una gran dispersión en sus propiedades físico mecánicas, grandes costes económicos asociados a la caracterización mecánica del material para su uso en aplicaciones estructurales. Por ello, nace la necesidad de plantear un sistema simplificado que permita estimar las propiedades mecánicas de la Guadua, que se pueda ejecutar en cualquier lugar remoto y que también reduzca los costes asociados al transporte de muestras y pruebas de laboratorio. Esta tesis doctoral propone una metodología que permite determinar las características mecánicas de la Guadua angustifolia que crece en la región Andina de Colombia. Se ha llevado a cabo una amplia campaña experimental donde se realizaron 2917 ensayos de laboratorio que tuvieron en cuenta variables como la procedencia, la temperatura y la pluviosidad, así como el diámetro y espesor de pared del tallo. Con ayuda de análisis estadísticos que permitieron eliminar los datos atípicos obtenidos de los ensayos, se han evaluado las propiedades mecánicas de la Guadua: resistencia a tracción, compresión, corte y flexión. Dichas variables se han correlacionado mediante modelos estadísticos para así determinar su relación con los esfuerzos mecánicos resultantes de la campaña experimental. Estos modelos estadísticos, basados y calibrados con multitud de datos experimentales, han perseguido la predicción de los valores de esfuerzo últimos del material antes de su extracción en el bosque y directamente desde un trabajo sencillo de campo. Los resultados y conclusiones alcanzadas en esta tesis doctoral serán de gran utilidad para científicos, arquitectos, ingenieros y constructores en general, ya que permitirán estimar propiedades de la Guadua de una manera económica, precisa y rápida. / [CA] L'any 2010 el reglament Colombià de construcció sismeresistent (*NSR-10) estableix el procediment de disseny basat en el mètode dels esforços admissibles, per a utilitzar la Guadua angustifolia Kunth com a material de construcció. A la regió Andina de Colòmbia hi ha gran presència de boscos naturals de guadua. Però les condicions geogràfiques i ambientals (ex. temperatura, pluviositat, altura sobre el nivell de la mar, etc.) dificulten el seu aprofitament com a material constructiu. Més encara, la seua localització està principalment en llocs de difícil accés no sols generant una gran dispersió en les seues propietats físic mecàniques, sinó també els costos associats per a identificar la seua resistència per a aplicacions estructurals. Com a conseqüència directa, naix la necessitat de plantejar un sistema simplificat que permeta estimar aquestes propietats que no sols es puga executar en el lloc concret de la plantació, sinó que també reduïsca els costos de transport i proves de laboratori. Aquesta tesi doctoral proposa una solució que permet determinar les característiques mecàniques de la Guadua angustifolia Kunth que creix a la regió andina de Colòmbia. Per a això, en primer lloc, es van realitzar 2917 assajos de laboratori relacionant variables com l'origen d'extracció, la temperatura i pluviositat, i el diàmetre i grossària de paret de la tija. Amb aquests assajos, i amb ajuda de l'estadística per eliminar dades atípiques, es caracteritzaren les propietats mecàniques de la guadua com la seua resistència a la tracció, compressió, tallant i moment. Posteriorment, amb tots aquests resultats, es va modelar estadísticament les relacions entre les variables considerades i els esforços mecànics. El propòsit d'aquests models ha sigut el de predir valors d'esforços últims d'aquest material en camp abans de l'extracció i de la realització de qualsevol assaig mecànic. Aquests models són de gran importància perquè científics, arquitectes, enginyers i constructors en general, puguen estimar propietats de la guadua d'una manera econòmica, precisa i ràpida. / [EN] During 2010, Colombian seismic-resistant regulation for construction (NSR-10) established the design procedure using the admissible load method to use Guadua Angustifolia Kunth as a construction material. At the Colombian Andean region, there are a large number of Guadua forests. However, the geographical and environmental conditions (e.g. temperature, rainfall, height above sea level, etc.) limits its exploitation as a construction material. Moreover, these forests are mainly found at remote locations with difficult access, not only making its physical and mechanical properties greatly scattered but also increasing the costs related to identifying its strength for structural applications. As a direct consequence, the necessity of a simplified system that ease the estimation of these properties emerges, not only to foster on-field testing but also to reduce transport and laboratory testing costs. This doctoral thesis proposes one solution to determine the mechanical properties of the Guadua Angustifolia Kunth that grows at Colombian Andean region. For this, 2917 laboratory tests were done to relate variables such as the origin, temperature and rainfall, and the stem diameter and thickness. From this first part of the study, mechanical strength properties of the guadua such as tension, compression, shear and bending were determined with the help of statistical filters to eliminate the abnormal data from tests. Then, all this data was used to statistically model the relationship within the variables and the mechanical strength. The goal of these models is to predict mechanical ultimate strength at the field without doing physical extraction or mechanical tests. These models will enable scientists, architects and, in general, anyone in the construction sector to easily estimate the guadua's mechanical properties in a cheaper, accurate and efficient manner. / Lozano Peña, JE. (2021). Determinación de los esfuerzos últimos de la Guadua Angustifolia en la región andina de Colombia correlacionada con variables de clima [Tesis doctoral]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/165379
6

Earthquake Resistant Analysis for Design of Bamboo Reinforced Housing

Unknown Date (has links)
This study is directed to the application of bamboo as alternative material in civil construction. The study also extends to discuss the new applications of bamboo Angustifolia Kunth in construction, such as shear walls and bamboo boards. The investigation involved the following tasks: (a) Evaluation of physical and mechanical properties of bamboo Angustifolia Kunth; (b) Proposing a new type of joint (connection) using culms and natural coupling assembly which can be used in bamboo frame structures. Bamboo dowels are used to create a monolithic joint to support gravitational and lateral forces efficiently; (c) Evaluating the behavior of bamboo Angustifolia Kunth through extensive laboratory work in order to determine the stresses that structural elements such as columns and beams can support under the action of gravitational and lateral external load, and then comparing with the permissible stresses given by the design and construction codes in each region; and (d) Conducting theoretical dynamic analysis of bamboo frame structures using Newmark Beta method and experimental validation to determine maximum values of acceleration, velocity and displacement. The information needed for this analysis are taken from the earthquake El Centro in California on 1940. From the results of this study, it can be concluded that the use of Angustifolia Kunth bamboo for civil structures composed only of bamboo elements offer safety, are economical and offers rapid construction method. This is very suitable for tropical and semitropical places preferably at an average of 2500 meter above the sea level, and advisable if they are located around the fire belt susceptible to seismic forces and earthquakes. It may be an ideal solution for low income populations in need of an immediate housing solution. / Includes bibliography. / Dissertation (Ph.D.)--Florida Atlantic University, 2018. / FAU Electronic Theses and Dissertations Collection
7

Chuva de sementes e estabelecimento de plântulas em ambientes com bambus na Mata Atlântica

Rother, Débora Cristina [UNESP] 29 May 2006 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:23:02Z (GMT). No. of bitstreams: 0 Previous issue date: 2006-05-29Bitstream added on 2014-06-13T19:08:48Z : No. of bitstreams: 1 rother_dc_me_rcla.pdf: 880592 bytes, checksum: 63ebac83ba6dcb09cddf42b5445e1892 (MD5) / Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) / Este trabalho teve como objetivos verificar como variam a chuva de sementes e o estabelecimento de plântulas entre ambientes colonizados (B) e não colonizados (SB) pelo bambu Guadua tagoara na floresta Atlântica do Parque Estadual Carlos Botelho, Sete Barras - SP. Foram utilizados 40 coletores e 40 parcelas de 1m2 em cada ambiente com monitoramento mensal no período de um ano. SB apresentou 38,71% mais sementes que B, maior riqueza, menor diversidade e equidade. Os ambientes mostraram uma alta similaridade no número de espécies de sementes em comum e com abundâncias semelhantes. SB apresentou maior média de sementes/mês e maior média de sementes/espécie. A densidade absoluta de sementes por coletor não variou entre ambientes, entretanto variou entre meses. Em relação às plântulas, B apresentou maior abundância, maior densidade, maior riqueza, maior dominância de Euterpe edulis, entretanto menor diversidade e equidade que SB. Os dois ambientes se apresentaram com baixa similaridade na composição e na abundância de plântulas por espécie. Em B houve maior média de plântulas/mês enquanto a média de plântulas/espécie foi semelhante entre ambientes. A densidade absoluta de plântulas de E. edulis variou entre meses e ambientes, com maior número em B. Para as demais espécies a diferença se deu entre ambientes e meses, porém maior número em SB. Quando analisadas todas as plântulas em conjunto houve diferença entre meses e ambientes. Maior média de plântulas emergiram e morreram no ambiente com bambu a cada mês. A taxa de sobrevivência variou segundo o tipo de ambiente e ao longo do ano. Nos dois ambientes E. edulis foi a única espécie que não apresentou qualquer tipo de limitação demográfica... / This project aim to evaluate how the seed rain and the seedling establishment varied between environments with (B) and without (WB) the bamboo Guadua tagoara in the Atlantic forest of Carlos Botelho State Park, Sete Barras - SP. Forty traps and forty plots of 1m2 were placed within each patch type during one year of monthly monitoring. We recorded higher richness and more seeds in WB than in B, nonetheless, diversity and equitability were lower. Both environments showed high similarity in composition and abundance of seeds per specie. The average of seeds per month and seeds per specie was higher in WB. Also, the absolute density of seeds per trap varied predictable in time but there was not difference between B and WB. In respect to seedlings, B environment showed higher abundance, density, richness and dominance of Euterpe edulis, although diversity and equitability were lower than in WB. We found low similarity between B and WB environments in seedlings composition and abundance per specie. The average of seedlings per month was higher in B while the average of seedlings per specie was similar. The absolute density of E. edulis and other species seedlings varied in time in both environments, showing more seedlings density of the former in B and more seedlings density of the later in WB. When all species were analyzed together, seedling density was different between environments and months. The average of seedlings that emerged and died was higher in B environment. The survival rate varied between environments and in time. We found that E. edulis was the only specie that did not show any demographic limitations between environments. Seed rain did not vary between environments in relation to the specie composition as much as in the seed quantity... (Complete abstract, click electronic access below)
8

Guadua chacoensis in Bolivia : - an investigation of mechanical properties of a bamboo species

Lindholm, Maria, Palm, Sara January 2007 (has links)
This Master thesis has been performed at CTD- the Centre for Wood Technology and Design at the University of Linköping and has been carried out in Santa Cruz de la Sierra in Bolivia. The objective of this thesis is to study the mechanical properties and uses of Guadua chacoensis, a bamboo native to Bolivia. Throughout history, bamboo has been used in many countries for a variety of purposes. In Asia bamboo is an important raw-material for buildings and furniture. It is also used for making paper and for land rehabilitation and fuel. In South America many countries, among them Bolivia, have great potential to use bamboo in the same way. One of the key ideas with this Master thesis is to make a contribution to support the Bolivian economy and welfare by elucidate this, hitherto undeveloped, natural resource. This thesis is a Minor field study partly financed by Sida- the Swedish International Development Cooperation Agency. During the field study theoretical studies were made, collecting local and international information about bamboo and Guadua chacoensis in particular. Laboratory tests were prepared and conducted at UPSA- the Private University of Santa Cruz de la Sierra and several localities of the plant were visited. Through tensile-, bending- and hardness test it is found that Guadua chacoensis is a flexible, medium soft material and is comparable with European oak when it comes to the tensile strength. This leads to the conclusion that this bamboo species, among other fields of applications, can be used for constructions, like houses and bridges, and furniture manufacturing. / Diese Diplomarbeit wurde durch das CTD- Zentrum für Holztechnik und Design an der Universität Linköping betreut und in Santa Cruz de la Sierra in Bolivien durchgeführt. Das Ziel dieser Arbeit ist es die mechanische Beanspruchung und die Anwendungen von Guadua chacoensis , einer bolivischen Bambusart, zu untersuchen. Bambus wurde in der Vergangenheit in vielen Ländern für die unterschiedlichsten Anwendungen wie zum Beispiel Häuser, Werkzeug, Möbel, Lebensmittel, Treibstoff und Papier verwendet. In meisten asiatischen Ländern ist Bambus ein wichtiger Rohstoff für kleine und mittlere Unternehmen. Damit werden Arbeitsplätze geschaffen, was der Bevölkerung hilft die Armutsgrenze zu überwinden. Auch in Lateinamerika haben viele Länder, wie zum Beispiel Bolivien, die Chance Bambus in der gleichen Weise zu nutzen. Ein zentraler Gedanke dieser Arbeit ist es daher eine Grundlage für die bolivische Wirtschaft zu schaffen damit dieser bislang kaum entwickelte Rohstoff genutzt werden kann. Diese Arbeit wurde von Sida- der Schwedischen Internationalen Entwicklungsorganisation, teilweise finanziell unterstützt. Im Rahmen der durchgeführten Studie wurden sowohl theoretische Aspekte betrachtet, als auch Versuche im Labor der privaten Universität von Santa Cruz de la Sierra durchgeführt. Des Weiteren wurden verschiedene Arten des Bambus in der Natur untersucht. Biege- Streck- und Festigkeitsversuche haben gezeigt, dass Guadua chacoensis ein flexibles und weiches Material ist. Von den Streckeigenschaften ist es mit europäischer Eiche zu vergleichen. Diese Ergebnisse führen zu der Schlussfolgerung, dass Guadua chacoensis für die Konstruktion von Häusern und Brücken, für die Herstellung von Möbeln und andere ähnliche Anwendungen eingesetzt werden kann. / Esta tesis ha sido realizada en el Centro de Ciencia de Madera y Diseño- CTD de la Universidad de Linköping y ha sido llevada a cabo en la ciudad de Santa Cruz de la Sierra, Bolivia. El objetivo de la tesis es estudiar los propiedades mecánicas y usos de la Guadua chacoensis, un bambú nativo de Bolivia. A lo largo de la historia, el bambú ha sido utilizado en muchas localidades del mundo en distintas aplicaciones, vale mencionar: viviendas, herramientas, muebles, alimentos, combustible, papel y para rehabilitación de la tierra. En casi todos los países Asiáticos el bambú es un recurso importante para empresas de tamaño pequeño y mediano, proporcionando empleo y contrarrestando la pobreza. En América Latina muchos países, incluyendo Bolivia, tienen potencial para aprovechar el bambú del mismo modo. Una de las ideas más importantes de la tesis es hacer una contribución para apoyar a la economía de Bolivia, la cual, hasta ahora, ha desarrollado muy poco este recurso natural. La tesis es un Minor field study parcialmente financiado por Asdi- la Agencia Sueca de Cooperación Internacional para el Desarrollo. Durante el Minor field study estudios teóricos fueron realizados, acumulando información nacional e internacional sobre bambú y Guadua chacoensis en particular. Para examinar los propiedades mecánicos de la Guadua chacoensis, pruebas de laboratorio fueron preparadas y efectuadas en la Universidad Privada de Santa Cruz de la Sierra. Asimismo, muchas áreas con bosques naturales donde crece la especie fueron visitadas. A través de pruebas de laboratorio de tracción, flexión y dureza ha sido demostrado que la Guadua chacoensis es un material flexible y de dureza media, comparable con el roble europeo cuando se trata de la fuerza de tracción. Eso tiene como resultado que la Guadua chacoensis, entre otros campos de aplicación, puede ser usada para construcciones, como casas y puentes, y para la manufacturación de muebles. / Detta examensarbetete har gjorts vid CTD- Centrum för Träteknik och Design vid Linköpings universitet och har utförts i Santa Cruz de la Sierra i Bolivia. Syftet med detta examensarbete är att studera de mekaniska egenskaperna och användningsområden för Guadua chacoensis, en boliviansk bambuart. Genom historien har bambu använts i en mängd olika applikationer såsom hus, verktyg, möbler, mat, bränsle, papper och land-rehabilitering. I de flesta asiatiska länder är bambu en viktig resurs för små- och medelstora företag vilket skapar arbetstillfällen och motverkar fattigdom. I Sydamerika finns många länder, däribland Bolivia, vilka har stora möjligheter att utnyttja bambu på samma sätt. En av huvudidéerna med detta examensarbete är att kunna gynna den bolivianska välfärden genom att belysa denna, hittills outvecklade naturresurs. Detta examensarbete är en Minor field study, delvis finansierad av Sida, styrelsen för internationellt utvecklingssamarbete. Under fältarbetet genomfördes teoretiska studier då internationell och inhemsk information om bambu, speciellt om Guadua chacoensis, samlades in. Olika områden där arten växer besöktes och hållfasthetstekniska tester genomfördes vid UPSA- Universidad Privada de Santa Cruz de la Sierra. Genom drag-, böj- och hårdhetsprovning har det påvisats att Guadua chacoensis är ett böjligt och medelhårt material med en draghållfasthet som är jämförbar med den för Europeisk ek. Detta gör att denna bambuart lämpar sig bland annat för konstruktioner, såsom hus och broar, samt möbeltillverkning.
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Guadua chacoensis in Bolivia : - an investigation of mechanical properties of a bamboo species

Lindholm, Maria, Palm, Sara January 2007 (has links)
<p>This Master thesis has been performed at CTD- the Centre for Wood Technology and Design at the University of Linköping and has been carried out in Santa Cruz de la Sierra in Bolivia.</p><p>The objective of this thesis is to study the mechanical properties and uses of Guadua chacoensis, a bamboo native to Bolivia. Throughout history, bamboo has been used in many countries for a variety of purposes. In Asia bamboo is an important raw-material for buildings and furniture. It is also used for making paper and for land rehabilitation and fuel. In South America many countries, among them Bolivia, have great potential to use bamboo in the same way. One of the key ideas with this Master thesis is to make a contribution to support the Bolivian economy and welfare by elucidate this, hitherto undeveloped, natural resource.</p><p>This thesis is a Minor field study partly financed by Sida- the Swedish International Development Cooperation Agency. During the field study theoretical studies were made, collecting local and international information about bamboo and Guadua chacoensis in particular. Laboratory tests were prepared and conducted at UPSA- the Private University of Santa Cruz de la Sierra and several localities of the plant were visited.</p><p>Through tensile-, bending- and hardness test it is found that Guadua chacoensis is a flexible, medium soft material and is comparable with European oak when it comes to the tensile strength. This leads to the conclusion that this bamboo species, among other fields of applications, can be used for constructions, like houses and bridges, and furniture manufacturing.</p> / <p>Diese Diplomarbeit wurde durch das CTD- Zentrum für Holztechnik und Design an der Universität Linköping betreut und in Santa Cruz de la Sierra in Bolivien durchgeführt.</p><p>Das Ziel dieser Arbeit ist es die mechanische Beanspruchung und die Anwendungen von Guadua chacoensis , einer bolivischen Bambusart, zu untersuchen. Bambus wurde in der Vergangenheit in vielen Ländern für die unterschiedlichsten Anwendungen wie zum Beispiel Häuser, Werkzeug, Möbel, Lebensmittel, Treibstoff und Papier verwendet.</p><p>In meisten asiatischen Ländern ist Bambus ein wichtiger Rohstoff für kleine und mittlere Unternehmen. Damit werden Arbeitsplätze geschaffen, was der Bevölkerung hilft die Armutsgrenze zu überwinden. Auch in Lateinamerika haben viele Länder, wie zum Beispiel Bolivien, die Chance Bambus in der gleichen Weise zu nutzen. Ein zentraler Gedanke dieser Arbeit ist es daher eine Grundlage für die bolivische Wirtschaft zu schaffen damit dieser bislang kaum entwickelte Rohstoff genutzt werden kann.</p><p>Diese Arbeit wurde von Sida- der Schwedischen Internationalen Entwicklungsorganisation, teilweise finanziell unterstützt. Im Rahmen der durchgeführten Studie wurden sowohl theoretische Aspekte betrachtet, als auch Versuche im Labor der privaten Universität von Santa Cruz de la Sierra durchgeführt. Des Weiteren wurden verschiedene Arten des Bambus in der Natur untersucht.</p><p>Biege- Streck- und Festigkeitsversuche haben gezeigt, dass Guadua chacoensis ein flexibles und weiches Material ist. Von den Streckeigenschaften ist es mit europäischer Eiche zu vergleichen. Diese Ergebnisse führen zu der Schlussfolgerung, dass Guadua chacoensis für die Konstruktion von Häusern und Brücken, für die Herstellung von Möbeln und andere ähnliche Anwendungen eingesetzt werden kann.</p> / <p>Esta tesis ha sido realizada en el Centro de Ciencia de Madera y Diseño- CTD</p><p>de la Universidad de Linköping y ha sido llevada a cabo en la ciudad de Santa Cruz de la Sierra, Bolivia.</p><p>El objetivo de la tesis es estudiar los propiedades mecánicas y usos de la</p><p>Guadua chacoensis, un bambú nativo de Bolivia. A lo largo de la historia, el bambú ha sido utilizado en muchas localidades del mundo en distintas aplicaciones, vale mencionar: viviendas, herramientas, muebles, alimentos, combustible, papel y para rehabilitación de la tierra. En casi todos los países Asiáticos el bambú es un recurso importante para empresas de tamaño pequeño y mediano, proporcionando empleo y contrarrestando la pobreza.</p><p>En América Latina muchos países, incluyendo Bolivia, tienen potencial para aprovechar el bambú del mismo modo. Una de las ideas más importantes de la tesis es hacer una contribución para apoyar a la economía de Bolivia, la cual, hasta ahora, ha desarrollado muy poco este recurso natural.</p><p>La tesis es un Minor field study parcialmente financiado por Asdi- la Agencia Sueca de Cooperación Internacional para el Desarrollo. Durante el Minor field study estudios teóricos fueron realizados, acumulando información nacional e internacional sobre bambú y Guadua chacoensis en particular. Para examinar los propiedades mecánicos de la Guadua chacoensis, pruebas de laboratorio fueron preparadas y efectuadas en la Universidad Privada de Santa Cruz de la Sierra. Asimismo, muchas áreas con bosques naturales donde crece la especie fueron visitadas.</p><p>A través de pruebas de laboratorio de tracción, flexión y dureza ha sido demostrado que la Guadua chacoensis es un material flexible y de dureza media, comparable con el roble europeo cuando se trata de la fuerza de tracción. Eso tiene como resultado que la Guadua chacoensis, entre otros campos de aplicación, puede ser usada para construcciones, como casas y puentes, y para la manufacturación de muebles.</p> / <p>Detta examensarbetete har gjorts vid CTD- Centrum för Träteknik och Design vid Linköpings universitet och har utförts i Santa Cruz de la Sierra i Bolivia.</p><p>Syftet med detta examensarbete är att studera de mekaniska egenskaperna och användningsområden för Guadua chacoensis, en boliviansk bambuart. Genom historien har bambu använts i en mängd olika applikationer såsom hus, verktyg, möbler, mat, bränsle, papper och land-rehabilitering. I de flesta asiatiska länder är bambu en viktig resurs för små- och medelstora företag vilket skapar arbetstillfällen och motverkar fattigdom. I Sydamerika finns många länder, däribland Bolivia, vilka har stora möjligheter att utnyttja bambu på samma sätt. En av huvudidéerna med detta examensarbete är att kunna gynna den bolivianska välfärden genom att belysa denna, hittills outvecklade naturresurs.</p><p>Detta examensarbete är en Minor field study, delvis finansierad av Sida, styrelsen för internationellt utvecklingssamarbete. Under fältarbetet genomfördes teoretiska studier då internationell och inhemsk information om bambu, speciellt om Guadua chacoensis, samlades in. Olika områden där arten växer besöktes och hållfasthetstekniska tester genomfördes vid UPSA- Universidad Privada de Santa Cruz de la Sierra.</p><p>Genom drag-, böj- och hårdhetsprovning har det påvisats att Guadua chacoensis är ett böjligt och medelhårt material med en draghållfasthet som är jämförbar med den för Europeisk ek. Detta gör att denna bambuart lämpar sig bland annat för konstruktioner, såsom hus och broar, samt möbeltillverkning.</p>
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Thermo-hydro-mechanically modified cross-laminated Guadua-bamboo panels

Archila Santos, Hector Fabio January 2015 (has links)
Guadua angustifolia Kunth (Guadua) is a bamboo species native to South and Central America that has been widely used for structural applications in small and large-scale buildings, bridges and temporary structures. Currently, its structural use is regulated within seismic resistant building codes in countries such as Peru and Colombia. Nevertheless, Guadua remains a material for vernacular construction associated with high levels of manual labour and structural unpredictability. Guadua buildings are limited to two storeys due to the overall flexibility of the slender and hollow culms and its connection systems. Its axial specific stiffness is comparable to that of steel and hardwoods, but unlike wood, Guadua’s hollow structure and lack of ray cells render it prone to buckling along the grain and to transverse crushing. As a result, Guadua’s mainstream use in construction and transformation into standard sizes or engineered Guadua products is scarce. Therefore, this work focussed on the development of standardised flat industrial structural products from Guadua devising replicable manufacturing technologies and engineering methods to measure and predict their mechanical behaviour. Cross-laminated Guadua panels were developed using thermohydro-mechanically modified and laminated flat Guadua strips glued with a high performance resin. Guadua was subjected to thermo-hydro-mechanical (THM) treatments that modified its microstructure and mechanical properties. THM treatment was applied to Guadua with the aim of tackling the difficulties in the fabrication of standardised construction materials and to gain a uniform fibre content profile that facilitated prediction of mechanical properties for structural design. Densified homogenous flat Guadua strips (FGS) were obtained. Elastic properties of FGS were determined in tension, compression and shear using small-clear specimens. These properties were used to predict the structural behaviour of G-XLam panels comprised of three and five layers (G-XLam3 and G-XLam5) by numerical methods. The panels were assumed as multi-layered systems composed of contiguous lamellas with orthotropic axes orientated at 0º and 90º. A finite element (FE) model was developed, and successfully simulated the response of G-XLam3 & 5 panels virtually loaded with the same boundary conditions as the following experimental tests on full-scale panels. G-XLam3 and G-XLam5 were manufactured and their mechanical properties evaluated by testing large specimens in compression, shear and bending. Results from numerical, FE predictions and mechanical testing demonstrated comparable results. Finally, design and manufacturing aspects of the G-XLam panels were discussed and examples of their architectural and structural use in construction applications such as mid-rise buildings, grid shells and vaults are presented. Overall, this research studies THM treatments applied to Guadua in order to produce standardised engineered Guadua products (EGP), and provides guidelines for manufacturing, testing, and for the structural analysis and design with G-XLam panels. These factors are of key importance for the use of Guadua as a mainstream material in construction.

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