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Elio Jose Santini - One of the best experts on this subject based on the ideXlab platform.
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Resistência ao impacto da madeira de nogueira-pecã em diferentes condições de umidade Impact strength of nogueira-pecã wood on different moisture conditions
Universidade Federal de Santa Maria, 2012Co-Authors: Rafael Beltrame, Clovis Roberto Haselein, Darci Alberto Gatto, Marilia Lazarotto, Bruno Dufau Mattos, Elio Jose SantiniAbstract:Os estudos de resistência da madeira ao impacto referem-se à eficiência com que este material absorve energia de um impacto e dissipa-a sem danos a sua estrutura. Dessa forma, o objetivo deste estudo foi avaliar a influência do teor de umidade na resistência ao impacto da madeira de nogueira-pecã (Carya illinoinensis). Para tanto, foram utilizadas árvores procedentes de duas regiões fisiográficas do estado do Rio Grande do Sul. Os corpos de prova, em condições de equilíbrio a 12% de umidade e saturados, foram submetidos ao impacto utilizando-se pêndulo de CHARPY, e avaliados quanto à resistência oferecida com a aplicação da carga nos planos tangencial e radial e posições de retirada (medula - casca) nas toras, para as duas regiões fisiográficas em cada condição de umidade. Para auxiliar na interpretação dos dados, determinou-se a massa específica aparente a 12% e saturada, trabalho absorvido, coeficiente de resiliência e a cota dinâmica. Pôde-se verificar, por meio dos resultados, que a madeira de nogueira-pecã é mais resistente ao impacto na condição saturada.The studies of wood impact strength refers to the efficiency of this material in absorb impact energy and dissipate it without structural damages. The present study aimed to evaluate the influence of moisture content on the impact strength of nogueira-pecã (Carya illinoinensis) wood. For this, trees from two physiographic regions of state of Rio Grande do Sul were used. The samples, stabilized at 12% of moisture content and in green conditions (saturated), were submitted to impact tests through a CHARPY pendulum, and were evaluated for the resistance to the application of loads in the tangential and radial sections, and in the positions of the log (pith-bark) for the two physiographic regions at each moisture condition. Moreover, the apparent specific gravity at 12% and in green conditions (saturated), the absorbed work, the resilience coefficient and the dynamic quote were determined. The main results showed that the nogueira-pecã wood is more resistant to the impact when it is in green conditions
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Wood natural resistance of seven forest species to white rot caused by Pycnoporus sanguineus
Universidade Federal de Lavras, 2012Co-Authors: Karina Soares Modes, Elio Jose Santini, Marilia Lazarotto, Rafael Beltrame, Magnos Alan Vivian, Marlove Fátima Brião MunizAbstract:This research evaluated the natural resistance of: Platanus x acerifolia, Luehea divaricate, Carya illinoinensis, Peltophorum dubium, Araucaria angustifolia, Eucalyptus grandis and Hovenia dulcis, to accelerated decay of the white-rot fungus Pycnoporus sanguineus. The Specific Density at 12% was determinated. The accelerated decay test was conducted with glass bottles (capacity of 500 mL) filled with 100 g of moist soil, autoclaved, and kept at 25 °C. The initial establishment of fungal colonies on plates was supported by samples of Pinus elliottii sapwood. In this study, three samples of dimensions 9.0 x 25.0 x 25.0 mm were used for each species evaluated and, after 16 weeks of incubation, the percentage loss of mass was calculated. The degree of natural resistance was performed according to the percentages of mass loss. The results obtained from weight loss were compared by Tukey test at 5%. The natural resistance of woods was not influenced by specific gravity. The wood of Carya illinoinensis, Eucalyptus grandis, Platanus x acerifolia, Luehea divaricata and Peltophorum dubium were classified as very resistant, Houvenia dulcis as resistant and Araucaria angustifolia as moderate resistant
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ESTIMATION OF AGE OF SEGREGATION OF JUVENILE AND MATURE Carya illinoinensis (Wangenh) K. Koch WOOD USING ANATOMICAL CHARACTERISTICS
Universidade Federal de Santa Maria, 2010Co-Authors: Darci Alberto Gatto, Clovis Roberto Haselein, Diego Martins Stangerlin, Leandro Calegari, Ediane Andréia Buligon, Rafael Rodolfo De Melo, Rômulo Trevisan, Elio Jose SantiniAbstract:Knowledge of the demarcation of juvenile and mature wood is essential both for wood technology and forest management. Thinning, in most cases, must take into account this parameter, as the juvenile wood has inferior characteristics compared to mature wood, and different proportions of each type of wood will affect the quality and the use of the wood. Thus, this study aimed to determine the age of maturation of the wood using anatomical characteristics of Carya illinoinensis (Wangenh) K. Koch wood, through the segregation of juvenile and mature wood. Three adult trees, of good trunk, with diameter greater than 30 cm DBH, were chosen from the region Encosta Superior do Nordeste in the State of the Rio Grande do Sul. From each tree, one disc was removed, with approximately 2 cm in thickness, at 0.10 m in height of the trunk. From each disc was removed a central portion of 2 cm in width, well oriented in the radial direction, including the pith in the center, and this central portion was divided into samples “A” and “B”. One of these two samples was selected for separation of the initial wood of each growth ring for maceration (Jeffrey method ). First, the length, width and diameter of the lumen of one hundred fibers were measured in the first ring (next to the bark) and later, thirty fibers were defined per growth ring as statistically sufficient for the assay. The thickness of the walls of the fiber was taken as the half of the difference of the diameter of the fiber and the lumen. The segregation of the two types of wood was defined by the radial variation (pith-bark) of the anatomical characteristics (length, diameter, width of the lumen and thickness of the wall of fibers), through two simple linear regressions. The results indicate that the fiber length is the best characteristic for the definition of the year of segregation. The age of segregation of juvenile-mature wood was defined as 16 years. In their turn, the anatomical parameters, diameter of fibers, width of the lumen and thickness of the wall of fibers were shown to be inadequate for estimating the age of segregation.
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ESTIMATIVA DA IDADE DE SEGREGAÇÃO DO LENHO JUVENIL E ADULTO DE Carya illinoinensis (Wangenh) K. Koch POR MEIO DE PARÂMETROS ANATÔMICOS DA MADEIRA
Universidade Federal de Santa Maria, 2010Co-Authors: Darci Alberto Gatto, Clovis Roberto Haselein, Diego Martins Stangerlin, Leandro Calegari, Ediane Andréia Buligon, Rafael Rodolfo De Melo, Rômulo Trevisan, Elio Jose SantiniAbstract:Knowledge of the demarcation of juvenile and mature wood is essential both for wood technology and forest management. Thinning, in most cases, must take into account this parameter, as the juvenile wood has inferior characteristics compared to mature wood, and different proportions of each type of wood will affect the quality and the use of the wood. Thus, this study aimed to determine the age of maturation of the wood using anatomical characteristics of Carya illinoinensis (Wangenh) K. Koch wood, through the segregation of juvenile and mature wood. Three adult trees, of good trunk, with diameter greater than 30 cm DBH, were chosen from the region Encosta Superior do Nordeste in the State of the Rio Grande do Sul. From each tree, one disc was removed, with approximately 2 cm in thickness, at 0.10 m in height of the trunk. From each disc was removed a central portion of 2 cm in width, well oriented in the radial direction, including the pith in the center, and this central portion was divided into samples "A" and "B". One of these two samples was selected for separation of the initial wood of each growth ring for maceration (Jeffrey method ). First, the length, width and diameter of the lumen of one hundred fibers were measured in the first ring (next to the bark) and later, thirty fibers were defined per growth ring as statistically sufficient for the assay. The thickness of the walls of the fiber was taken as the half of the difference of the diameter of the fiber and the lumen. The segregation of the two types of wood was defined by the radial variation (pith-bark) of the anatomical characteristics (length, diameter, width of the lumen and thickness of the wall of fibers), through two simple linear regressions. The results indicate that the fiber length is the best characteristic for the definition of the year of segregation. The age of segregation of juvenile-mature wood was defined as 16 years. In their turn, the anatomical parameters, diameter of fibers, width of the lumen and thickness of the wall of fibers were shown to be inadequate for estimating the age of segregation
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TECHNOLOGICAL CHARACTERISTICS OF THE WOOD OF Luehea divaricata, Carya illinoinensis AND Platanus x acerifolia WHEN SUBMITTED TO BENDING
Universidade Federal de Santa Maria, 2009Co-Authors: Darci Alberto Gatto, Clovis Roberto Haselein, Miguel Antao Durlo, Elio Jose Santini, Leandro Calegari, José Newton Cardoso Marchiori, Diego Martins StangerlinAbstract:This work was conducted with the purpose of investigating bending characteristics of the wood of Platanus x acerifolia (Ait.) Willd., Luehea divaricata Mart. et Zucc and Carya illinoinensis (Wangenh) K. Koch. Such species were collected from non-managed forests located in Depressão Central and Encosta Superior do Nordeste, Rio Grande do Sul, Brazil. Five representative adult trees from each species per studied area were cut down, corresponding to a total of thirty trees. From the trunk, a 2.5 m long log was taken and, afterwards, transported to a sawmill for processing. A central 8 cm thick plank was sawn, from which samples for bending were manufactured. The samples were conditioned in standard room to a moisture content of approximately 14%. Then, the samples were placed in boiling water during 35 minutes and bended in rays of 16 and 21cm. For the qualification of the bending defects, the methodology presented by Vorreiter (1958) was used. Results showed that the wood of Carya illinoinensis (Wangenh) K. Koch had the best bending characteristics when compared to the other two species, independently of the ray bending tested. It seems that the ring porosity, characteristic of the Carya illinoinensis wood, contributed to the result. On the other hand, the wood of Platanus x acerifolia (Ait.) Willd. and Luehea divaricata Mart. et Zucc, with diffuse porosity and larger parenchyma proportion, presented more defective pieces.
Darci Alberto Gatto - One of the best experts on this subject based on the ideXlab platform.
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Resistência ao impacto da madeira de nogueira-pecã em diferentes condições de umidade Impact strength of nogueira-pecã wood on different moisture conditions
Universidade Federal de Santa Maria, 2012Co-Authors: Rafael Beltrame, Clovis Roberto Haselein, Darci Alberto Gatto, Marilia Lazarotto, Bruno Dufau Mattos, Elio Jose SantiniAbstract:Os estudos de resistência da madeira ao impacto referem-se à eficiência com que este material absorve energia de um impacto e dissipa-a sem danos a sua estrutura. Dessa forma, o objetivo deste estudo foi avaliar a influência do teor de umidade na resistência ao impacto da madeira de nogueira-pecã (Carya illinoinensis). Para tanto, foram utilizadas árvores procedentes de duas regiões fisiográficas do estado do Rio Grande do Sul. Os corpos de prova, em condições de equilíbrio a 12% de umidade e saturados, foram submetidos ao impacto utilizando-se pêndulo de CHARPY, e avaliados quanto à resistência oferecida com a aplicação da carga nos planos tangencial e radial e posições de retirada (medula - casca) nas toras, para as duas regiões fisiográficas em cada condição de umidade. Para auxiliar na interpretação dos dados, determinou-se a massa específica aparente a 12% e saturada, trabalho absorvido, coeficiente de resiliência e a cota dinâmica. Pôde-se verificar, por meio dos resultados, que a madeira de nogueira-pecã é mais resistente ao impacto na condição saturada.The studies of wood impact strength refers to the efficiency of this material in absorb impact energy and dissipate it without structural damages. The present study aimed to evaluate the influence of moisture content on the impact strength of nogueira-pecã (Carya illinoinensis) wood. For this, trees from two physiographic regions of state of Rio Grande do Sul were used. The samples, stabilized at 12% of moisture content and in green conditions (saturated), were submitted to impact tests through a CHARPY pendulum, and were evaluated for the resistance to the application of loads in the tangential and radial sections, and in the positions of the log (pith-bark) for the two physiographic regions at each moisture condition. Moreover, the apparent specific gravity at 12% and in green conditions (saturated), the absorbed work, the resilience coefficient and the dynamic quote were determined. The main results showed that the nogueira-pecã wood is more resistant to the impact when it is in green conditions
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segregation of pecan Carya illinoinensis wood by the radial specific gravity variation
Revista Brasileira de Ciências Agrárias (Agrária), 2012Co-Authors: Darci Alberto Gatto, Diego Martins Stangerlin, Leandro Calegari, M Da F Martins, P H G De Cademartori, Rafael BeltrameAbstract:This study aimed to estimate the age of segregation of juvenile and adult wood of walnut-pecan (Carya illinoinensis) by the radial specific gravity variation. A total of 10 mature trees were collected from two physiographic regions of the Rio Grande do Sul State, Brazil, being five trees from each region. A disc, with approximately 2 cm thick, was removed from each tree at 10 cm trunk height. A central portion of 2 cm in width was removed from each disc and this central portion was divided into two samples. Specimens measuring 1 x 2 x 2 cm were made, each in the radial direction of the disc, which were used to determinate the specific gravity and thus estimate the age of segregation of adult and juvenile wood of walnut-pecan. The segregation age was 12 years. However, the radial variation in specific gravity was not a great parameter to determine the segregation age of wood.
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ESTIMATION OF AGE OF SEGREGATION OF JUVENILE AND MATURE Carya illinoinensis (Wangenh) K. Koch WOOD USING ANATOMICAL CHARACTERISTICS
Universidade Federal de Santa Maria, 2010Co-Authors: Darci Alberto Gatto, Clovis Roberto Haselein, Diego Martins Stangerlin, Leandro Calegari, Ediane Andréia Buligon, Rafael Rodolfo De Melo, Rômulo Trevisan, Elio Jose SantiniAbstract:Knowledge of the demarcation of juvenile and mature wood is essential both for wood technology and forest management. Thinning, in most cases, must take into account this parameter, as the juvenile wood has inferior characteristics compared to mature wood, and different proportions of each type of wood will affect the quality and the use of the wood. Thus, this study aimed to determine the age of maturation of the wood using anatomical characteristics of Carya illinoinensis (Wangenh) K. Koch wood, through the segregation of juvenile and mature wood. Three adult trees, of good trunk, with diameter greater than 30 cm DBH, were chosen from the region Encosta Superior do Nordeste in the State of the Rio Grande do Sul. From each tree, one disc was removed, with approximately 2 cm in thickness, at 0.10 m in height of the trunk. From each disc was removed a central portion of 2 cm in width, well oriented in the radial direction, including the pith in the center, and this central portion was divided into samples “A” and “B”. One of these two samples was selected for separation of the initial wood of each growth ring for maceration (Jeffrey method ). First, the length, width and diameter of the lumen of one hundred fibers were measured in the first ring (next to the bark) and later, thirty fibers were defined per growth ring as statistically sufficient for the assay. The thickness of the walls of the fiber was taken as the half of the difference of the diameter of the fiber and the lumen. The segregation of the two types of wood was defined by the radial variation (pith-bark) of the anatomical characteristics (length, diameter, width of the lumen and thickness of the wall of fibers), through two simple linear regressions. The results indicate that the fiber length is the best characteristic for the definition of the year of segregation. The age of segregation of juvenile-mature wood was defined as 16 years. In their turn, the anatomical parameters, diameter of fibers, width of the lumen and thickness of the wall of fibers were shown to be inadequate for estimating the age of segregation.
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ESTIMATIVA DA IDADE DE SEGREGAÇÃO DO LENHO JUVENIL E ADULTO DE Carya illinoinensis (Wangenh) K. Koch POR MEIO DE PARÂMETROS ANATÔMICOS DA MADEIRA
Universidade Federal de Santa Maria, 2010Co-Authors: Darci Alberto Gatto, Clovis Roberto Haselein, Diego Martins Stangerlin, Leandro Calegari, Ediane Andréia Buligon, Rafael Rodolfo De Melo, Rômulo Trevisan, Elio Jose SantiniAbstract:Knowledge of the demarcation of juvenile and mature wood is essential both for wood technology and forest management. Thinning, in most cases, must take into account this parameter, as the juvenile wood has inferior characteristics compared to mature wood, and different proportions of each type of wood will affect the quality and the use of the wood. Thus, this study aimed to determine the age of maturation of the wood using anatomical characteristics of Carya illinoinensis (Wangenh) K. Koch wood, through the segregation of juvenile and mature wood. Three adult trees, of good trunk, with diameter greater than 30 cm DBH, were chosen from the region Encosta Superior do Nordeste in the State of the Rio Grande do Sul. From each tree, one disc was removed, with approximately 2 cm in thickness, at 0.10 m in height of the trunk. From each disc was removed a central portion of 2 cm in width, well oriented in the radial direction, including the pith in the center, and this central portion was divided into samples "A" and "B". One of these two samples was selected for separation of the initial wood of each growth ring for maceration (Jeffrey method ). First, the length, width and diameter of the lumen of one hundred fibers were measured in the first ring (next to the bark) and later, thirty fibers were defined per growth ring as statistically sufficient for the assay. The thickness of the walls of the fiber was taken as the half of the difference of the diameter of the fiber and the lumen. The segregation of the two types of wood was defined by the radial variation (pith-bark) of the anatomical characteristics (length, diameter, width of the lumen and thickness of the wall of fibers), through two simple linear regressions. The results indicate that the fiber length is the best characteristic for the definition of the year of segregation. The age of segregation of juvenile-mature wood was defined as 16 years. In their turn, the anatomical parameters, diameter of fibers, width of the lumen and thickness of the wall of fibers were shown to be inadequate for estimating the age of segregation
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TECHNOLOGICAL CHARACTERISTICS OF THE WOOD OF Luehea divaricata, Carya illinoinensis AND Platanus x acerifolia WHEN SUBMITTED TO BENDING
Universidade Federal de Santa Maria, 2009Co-Authors: Darci Alberto Gatto, Clovis Roberto Haselein, Miguel Antao Durlo, Elio Jose Santini, Leandro Calegari, José Newton Cardoso Marchiori, Diego Martins StangerlinAbstract:This work was conducted with the purpose of investigating bending characteristics of the wood of Platanus x acerifolia (Ait.) Willd., Luehea divaricata Mart. et Zucc and Carya illinoinensis (Wangenh) K. Koch. Such species were collected from non-managed forests located in Depressão Central and Encosta Superior do Nordeste, Rio Grande do Sul, Brazil. Five representative adult trees from each species per studied area were cut down, corresponding to a total of thirty trees. From the trunk, a 2.5 m long log was taken and, afterwards, transported to a sawmill for processing. A central 8 cm thick plank was sawn, from which samples for bending were manufactured. The samples were conditioned in standard room to a moisture content of approximately 14%. Then, the samples were placed in boiling water during 35 minutes and bended in rays of 16 and 21cm. For the qualification of the bending defects, the methodology presented by Vorreiter (1958) was used. Results showed that the wood of Carya illinoinensis (Wangenh) K. Koch had the best bending characteristics when compared to the other two species, independently of the ray bending tested. It seems that the ring porosity, characteristic of the Carya illinoinensis wood, contributed to the result. On the other hand, the wood of Platanus x acerifolia (Ait.) Willd. and Luehea divaricata Mart. et Zucc, with diffuse porosity and larger parenchyma proportion, presented more defective pieces.
Diego Martins Stangerlin - One of the best experts on this subject based on the ideXlab platform.
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segregation of pecan Carya illinoinensis wood by the radial specific gravity variation
Revista Brasileira de Ciências Agrárias (Agrária), 2012Co-Authors: Darci Alberto Gatto, Diego Martins Stangerlin, Leandro Calegari, M Da F Martins, P H G De Cademartori, Rafael BeltrameAbstract:This study aimed to estimate the age of segregation of juvenile and adult wood of walnut-pecan (Carya illinoinensis) by the radial specific gravity variation. A total of 10 mature trees were collected from two physiographic regions of the Rio Grande do Sul State, Brazil, being five trees from each region. A disc, with approximately 2 cm thick, was removed from each tree at 10 cm trunk height. A central portion of 2 cm in width was removed from each disc and this central portion was divided into two samples. Specimens measuring 1 x 2 x 2 cm were made, each in the radial direction of the disc, which were used to determinate the specific gravity and thus estimate the age of segregation of adult and juvenile wood of walnut-pecan. The segregation age was 12 years. However, the radial variation in specific gravity was not a great parameter to determine the segregation age of wood.
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ESTIMATION OF AGE OF SEGREGATION OF JUVENILE AND MATURE Carya illinoinensis (Wangenh) K. Koch WOOD USING ANATOMICAL CHARACTERISTICS
Universidade Federal de Santa Maria, 2010Co-Authors: Darci Alberto Gatto, Clovis Roberto Haselein, Diego Martins Stangerlin, Leandro Calegari, Ediane Andréia Buligon, Rafael Rodolfo De Melo, Rômulo Trevisan, Elio Jose SantiniAbstract:Knowledge of the demarcation of juvenile and mature wood is essential both for wood technology and forest management. Thinning, in most cases, must take into account this parameter, as the juvenile wood has inferior characteristics compared to mature wood, and different proportions of each type of wood will affect the quality and the use of the wood. Thus, this study aimed to determine the age of maturation of the wood using anatomical characteristics of Carya illinoinensis (Wangenh) K. Koch wood, through the segregation of juvenile and mature wood. Three adult trees, of good trunk, with diameter greater than 30 cm DBH, were chosen from the region Encosta Superior do Nordeste in the State of the Rio Grande do Sul. From each tree, one disc was removed, with approximately 2 cm in thickness, at 0.10 m in height of the trunk. From each disc was removed a central portion of 2 cm in width, well oriented in the radial direction, including the pith in the center, and this central portion was divided into samples “A” and “B”. One of these two samples was selected for separation of the initial wood of each growth ring for maceration (Jeffrey method ). First, the length, width and diameter of the lumen of one hundred fibers were measured in the first ring (next to the bark) and later, thirty fibers were defined per growth ring as statistically sufficient for the assay. The thickness of the walls of the fiber was taken as the half of the difference of the diameter of the fiber and the lumen. The segregation of the two types of wood was defined by the radial variation (pith-bark) of the anatomical characteristics (length, diameter, width of the lumen and thickness of the wall of fibers), through two simple linear regressions. The results indicate that the fiber length is the best characteristic for the definition of the year of segregation. The age of segregation of juvenile-mature wood was defined as 16 years. In their turn, the anatomical parameters, diameter of fibers, width of the lumen and thickness of the wall of fibers were shown to be inadequate for estimating the age of segregation.
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ESTIMATIVA DA IDADE DE SEGREGAÇÃO DO LENHO JUVENIL E ADULTO DE Carya illinoinensis (Wangenh) K. Koch POR MEIO DE PARÂMETROS ANATÔMICOS DA MADEIRA
Universidade Federal de Santa Maria, 2010Co-Authors: Darci Alberto Gatto, Clovis Roberto Haselein, Diego Martins Stangerlin, Leandro Calegari, Ediane Andréia Buligon, Rafael Rodolfo De Melo, Rômulo Trevisan, Elio Jose SantiniAbstract:Knowledge of the demarcation of juvenile and mature wood is essential both for wood technology and forest management. Thinning, in most cases, must take into account this parameter, as the juvenile wood has inferior characteristics compared to mature wood, and different proportions of each type of wood will affect the quality and the use of the wood. Thus, this study aimed to determine the age of maturation of the wood using anatomical characteristics of Carya illinoinensis (Wangenh) K. Koch wood, through the segregation of juvenile and mature wood. Three adult trees, of good trunk, with diameter greater than 30 cm DBH, were chosen from the region Encosta Superior do Nordeste in the State of the Rio Grande do Sul. From each tree, one disc was removed, with approximately 2 cm in thickness, at 0.10 m in height of the trunk. From each disc was removed a central portion of 2 cm in width, well oriented in the radial direction, including the pith in the center, and this central portion was divided into samples "A" and "B". One of these two samples was selected for separation of the initial wood of each growth ring for maceration (Jeffrey method ). First, the length, width and diameter of the lumen of one hundred fibers were measured in the first ring (next to the bark) and later, thirty fibers were defined per growth ring as statistically sufficient for the assay. The thickness of the walls of the fiber was taken as the half of the difference of the diameter of the fiber and the lumen. The segregation of the two types of wood was defined by the radial variation (pith-bark) of the anatomical characteristics (length, diameter, width of the lumen and thickness of the wall of fibers), through two simple linear regressions. The results indicate that the fiber length is the best characteristic for the definition of the year of segregation. The age of segregation of juvenile-mature wood was defined as 16 years. In their turn, the anatomical parameters, diameter of fibers, width of the lumen and thickness of the wall of fibers were shown to be inadequate for estimating the age of segregation
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TECHNOLOGICAL CHARACTERISTICS OF THE WOOD OF Luehea divaricata, Carya illinoinensis AND Platanus x acerifolia WHEN SUBMITTED TO BENDING
Universidade Federal de Santa Maria, 2009Co-Authors: Darci Alberto Gatto, Clovis Roberto Haselein, Miguel Antao Durlo, Elio Jose Santini, Leandro Calegari, José Newton Cardoso Marchiori, Diego Martins StangerlinAbstract:This work was conducted with the purpose of investigating bending characteristics of the wood of Platanus x acerifolia (Ait.) Willd., Luehea divaricata Mart. et Zucc and Carya illinoinensis (Wangenh) K. Koch. Such species were collected from non-managed forests located in Depressão Central and Encosta Superior do Nordeste, Rio Grande do Sul, Brazil. Five representative adult trees from each species per studied area were cut down, corresponding to a total of thirty trees. From the trunk, a 2.5 m long log was taken and, afterwards, transported to a sawmill for processing. A central 8 cm thick plank was sawn, from which samples for bending were manufactured. The samples were conditioned in standard room to a moisture content of approximately 14%. Then, the samples were placed in boiling water during 35 minutes and bended in rays of 16 and 21cm. For the qualification of the bending defects, the methodology presented by Vorreiter (1958) was used. Results showed that the wood of Carya illinoinensis (Wangenh) K. Koch had the best bending characteristics when compared to the other two species, independently of the ray bending tested. It seems that the ring porosity, characteristic of the Carya illinoinensis wood, contributed to the result. On the other hand, the wood of Platanus x acerifolia (Ait.) Willd. and Luehea divaricata Mart. et Zucc, with diffuse porosity and larger parenchyma proportion, presented more defective pieces.
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caracteristicas tecnologicas das madeiras de luehea divaricata Carya illinoinensis e platanus x acerifolia quando submetidas ao vergamento
Ciencia Florestal, 2008Co-Authors: Darci Alberto Gatto, Clovis Roberto Haselein, Jose Niewton Cardoso Marchiori, Miguel Antao Durlo, Elio Jose Santini, Leandro Calegari, Diego Martins StangerlinAbstract:This work was conducted with the purpose of investigating bending characteristics of the wood of Platanus x acerifolia (Ait.) Willd., Luehea divaricata Mart. et Zucc and Carya illinoinensis (Wangenh) K. Koch. Such species were collected from non-managed forests located in Depressao Central and Encosta Superior do Nordeste, Rio Grande do Sul, Brazil. Five representative adult trees from each species per studied area were cut down, corresponding to a total of thirty trees. From the trunk, a 2.5 m long log was taken and, afterwards, transported to a sawmill for processing. A central 8 cm thick plank was sawn, from which samples for bending were manufactured. The samples were conditioned in standard room to a moisture content of approximately 14%. Then, the samples were placed in boiling water during 35 minutes and bended in rays of 16 and 21cm. For the qualification of the bending defects, the methodology presented by Vorreiter (1958) was used. Results showed that the wood of Carya illinoinensis (Wangenh) K. Koch had the best bending characteristics when compared to the other two species, independently of the ray bending tested. It seems that the ring porosity, characteristic of the Carya illinoinensis wood, contributed to the result. On the other hand, the wood of Platanus x acerifolia (Ait.) Willd. and Luehea divaricata Mart. et Zucc, with diffuse porosity and larger parenchyma proportion, presented more defective pieces.
Santini, Elio José - One of the best experts on this subject based on the ideXlab platform.
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Estimation of age of segregation of juvenile and mature Carya illinoinensis (Wangenh) K. Koch wood using anatomical characteristics
Centro de Pesquisas Florestais - CEPEF Departamento de Ciências Florestais - DCFL Programa de Pós Graduação em Engenharia Florestal - PPGEF, 2012Co-Authors: Gatto, Darci Alberto, Haselein, Clovis Roberto, Calegari Leandro, Stangerlin, Diego Martins, Buligon, Ediane Andréia, De Melo, Rafael Rodolfo, Trevisan Rômulo, Santini, Elio JoséAbstract:Esse estudo teve como objetivo delimitar a idade de maturação do lenho utilizando-se de características anatômicas da madeira de Carya illinoinensis (Wangenh) K. Koch (nogueira-pecã) por meio da segregação dos lenhos juvenil e adulto. Para a tecnologia da madeira, aliada ao manejo florestal, é imprescindível o conhecimento da delimitação do lenho juvenil e adulto. Os desbastes, na grande maioria dos casos, devem levar em consideração esse parâmetro, já que o lenho juvenil possui características inferiores a do lenho adulto, e diferentes proporções de cada tipo de lenho vão interferir na qualidade e no uso da madeira. Para a realização do presente estudo, foram eleitas três árvores adultas, de fuste reto e cilíndrico, com DAP superior a 30 cm, localizadas na Encosta Superior do Nordeste do estado do Rio Grande do Sul. Foi retirado um disco por árvore, com aproximadamente 2 cm de espessura a 0,10 m de altura do tronco. De cada disco, retirou-se, com auxilio de uma serra-de-fita, uma bagueta central de 2,0 cm de largura, bem orientada no sentido radial, incluindo a medula no centro, dividiu-se então a bagueta em duas amostras “A” e “B”. Dessas, sorteou-se uma, e separou-se apenas o lenho inicial de cada anel de crescimento para a maceração (método de Jeffrey) conforme descrito por Burger e Richter (1991). Mediram-se, primeiramente, com auxílio de um microscópio ótico com régua micrométrica, o comprimento, largura e diâmetro do lume individual de cem fibras no primeiro anel de crescimento (próximo à casca), e, posteriormente, definiram-se trinta fibras, por anel de crescimento, como estatisticamente suficiente para o ensaio. A espessura das paredes das fibras foi obtida pela metade da diferença do diâmetro da fibra e do lume. A segregação dos dois tipos de lenho foi definida pela variação radial (medula-casca) das características anatômicas (comprimento, diâmetro, largura do lume e espessura da parede das fibras) por meio de duas regressões lineares simples. Os resultados indicaram que o comprimento de fibra é a melhor característica para a definição do ano de segregação. Utilizando-se essa variável, determinou-se o ano de segregação dos lenhos juvenil-adulto em 16 anos. Por sua vez, os parâmetros anatômicos, diâmetro das fibras, largura do lume e espessura da parede das fibras mostraram-se inadequados, para a estimativa da idade de segregação, em conseqüência dos baixos coeficientes de determinação (R2), altos erros de estimativa (Sxy) e baixos valores para Razão F, observados nos modelos estatísticos.Knowledge of the demarcation of juvenile and mature wood is essential both for wood technology and forest management. Thinning, in most cases, must take into account this parameter, as the juvenile wood has inferior characteristics compared to mature wood, and different proportions of each type of wood will affect the quality and the use of the wood. Thus, this study aimed to determine the age of maturation of the wood using anatomical characteristics of Carya illinoinensis (Wangenh) K. Koch wood, through the segregation of juvenile and mature wood. Three adult trees, of good trunk, with diameter greater than 30 cm DBH, were chosen from the region Encosta Superior do Nordeste in the State of the Rio Grande do Sul. From each tree, one disc was removed, with approximately 2 cm in thickness, at 0.10 m in height of the trunk. From each disc was removed a central portion of 2 cm in width, well oriented in the radial direction, including the pith in the center, and this central portion was divided into samples “A” and “B”. One of these two samples was selected for separation of the initial wood of each growth ring for maceration (Jeffrey method ). First, the length, width and diameter of the lumen of one hundred fibers were measured in the first ring (next to the bark) and later, thirty fibers were defined per growth ring as statistically sufficient for the assay. The thickness of the walls of the fiber was taken as the half of the difference of the diameter of the fiber and the lumen. The segregation of the two types of wood was defined by the radial variation (pith-bark) of the anatomical characteristics (length, diameter, width of the lumen and thickness of the wall of fibers), through two simple linear regressions. The results indicate that the fiber length is the best characteristic for the definition of the year of segregation. The age of segregation of juvenile-mature wood was defined as 16 years. In their turn, the anatomical parameters, diameter of fibers, width of the lumen and thickness of the wall of fibers were shown to be inadequate for estimating the age of segregation
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WOOD NATURAL RESISTANCE OF SEVEN FOREST SPECIES TO WHITE ROT CAUSED BY Pycnoporus sanguineus
UNIV FEDERAL LAVRAS-UFLA, 2012Co-Authors: Modes, Karina Soares, Lazarotto Marilia, Santini, Elio José, Beltrame Rafael, Vivian, Magnos Alan, Briao Muniz, Marlove FatimaAbstract:This research evaluated the natural resistance of Platanus x acerifolia, Luehea divaricate, Carya illinoinensis, Peltophorum dubium, Araucaria angustifolia, Eucalyptus grandis and Hovenia dulcis, to accelerated decay of the white-rot fungus Pycnoporus sanguineus. The Specific Density at 12% was determinated. The accelerated decay test was conducted with glass bottles (capacity of 500 mL) filled with 100 g of moist soil, autoclaved, and kept at 25 degrees C. The initial establishment of fungal colonies on plates was supported by samples of Pinus elliottii sapwood. In this study, three samples of dimensions 9.0 x 25.0 x 25.0 mm were used for each species evaluated and, after 16 weeks of incubation, the percentage loss of mass was calculated. The degree of natural resistance was performed according to the percentages of mass loss. The results obtained from weight loss were compared by Tukey test at 5%. The natural resistance of woods was not influenced by specific gravity The wood of Carya illinoinensis, Eucalyptus grandis, Platanus x acerifolia, Luehea divaricata and Peltophorum dubium were classified as very resistant, Houvenia dulcis as resistant and Araucaria angustifolia as moderate resistant
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Natural Durability Of Three Wood Species In Field Tests
Centro de Pesquisas Florestais - CEPEF Departamento de Ciências Florestais - DCFL Programa de Pós Graduação em Engenharia Florestal - PPGEF, 2011Co-Authors: De Melo, Rafael Rodolfo, Gatto, Darci Alberto, Haselein, Clovis Roberto, Santini, Elio José, Stangerlin, Diego Martins, Susin FelipeAbstract:Com o objetivo de avaliar a durabilidade natural da madeira, amostras de alburno e de cerne de Luehea divaricata (açoita-cavalo), Carya illinoinensis (nogueira-pecã) e Platanus x acerifolia (plátano), medindo 2,5 x 2,5 x 30,0 cm (radial x tangencial x longitudinal), foram submetidas a ensaios experimentais em um povoamento de Pinus e em campo aberto. Durante um ano, as amostras foram periodicamente pesadas e avaliadas pelo critério de notas, para determinar o percentual de perda de massa e índice de deterioração, respectivamente. Os resultados mostraram que, independente da espécie e do tipo de lenho, o ambiente dentro da floresta é mais favorável a deterioração da madeira do que fora dele. Apesar da elevada correlações entre a perda de massa e o índice de deterioração foram observadas variações na avaliação da durabilidade da madeira entre esses critérios. Para todas as espécies, a madeira proveniente do alburno foi a mais atacada. Para perda de massa não foi observada diferença entre as espécies avaliadas, entretanto, o índice de deterioração apontou o plátano como a mais atacada.This work aimed to evaluate the natural durability of heartwood and sapwood of Luehea divaricata , Carya illinoinensis and Platanus x acerifolia . Test samples measuring 2.5 x 2.5 x 30.0 cm (radial x tangential x longitudinal) were placed in a pine forest stand and an open field. During a year, the samples were repeatedly weighed and evaluated by a rating system to determine mass loss and decay index, respectively. The results showed that regardless of species and type of wood, the forest environment is more favourable to decay than that of the open field. Despite the high correlation between mass loss and decay index, variations in the durability of wood were found between these parameters. The wood from the internal section of the log (sapwood) was the more affected. For mass loss, no significant variation was observed for the species analyzed, however, for the decay index Platanus x acerifolia was shown to be the most affected
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Estimativa da idade de segregação do lenho juvenil a adulto de Carya illinoinensis (Wangenh) K. Koch por meio de parâmetros anatômicos da madeira
'Universidad Federal de Santa Maria', 2010Co-Authors: Gatto, Darci Alberto, Haselein, Clovis Roberto, Calegari Leandro, Stangerlin, Diego Martins, Buligon, Ediane Andréia, Trevisan Rômulo, Rafael Rodolfo De Melo, Santini, Elio JoséAbstract:Knowledge of the demarcation of juvenile and mature wood is essential both for wood technology and forest management. Thinning, in most cases, must take into account this parameter, as the juvenile wood has inferior characteristics compared to mature wood, and different proportions of each type of wood will affect the quality and the use of the wood. Thus, this study aimed to determine the age of maturation of the wood using anatomical characteristics of Carya illinoinensis (Wangenh) K. Koch wood, through the segregation of juvenile and mature wood. Three adult trees, of good trunk, with diameter greater than 30 cm DBH, were chosen from the region Encosta Superior do Nordeste in the State of the Rio Grande do Sul. From each tree, one disc was removed, with approximately 2 cm in thickness, at 0.10 m in height of the trunk. From each disc was removed a central portion of 2 cm in width, well oriented in the radial direction, including the pith in the center, and this central portion was divided into samples “A” and “B”. One of these two samples was selected for separation of the initial wood of each growth ring for maceration (Jeffrey method ). First, the length, width and diameter of the lumen of one hundred fibers were measured in the first ring (next to the bark) and later, thirty fibers were defined per growth ring as statistically sufficient for the assay. The thickness of the walls of the fiber was taken as the half of the difference of the diameter of the fiber and the lumen. The segregation of the two types of wood was defined by the radial variation (pith-bark) of the anatomical characteristics (length, diameter, width of the lumen and thickness of the wall of fibers), through two simple linear regressions. The results indicate that the fiber length is the best characteristic for the definition of the year of segregation. The age of segregation of juvenile-mature wood was defined as 16 years. In their turn, the anatomical parameters, diameter of fibers, width of the lumen and thickness of the wall of fibers were shown to be inadequate for estimating the age of segregation.Esse estudo teve como objetivo delimitar a idade de maturação do lenho utilizando-se de características anatômicas da madeira de Carya illinoinensis (Wangenh) K. Koch (nogueira-pecã) por meio da segregação dos lenhos juvenil e adulto. Para a tecnologia da madeira, aliada ao manejo florestal, é imprescindível o conhecimento da delimitação do lenho juvenil e adulto. Os desbastes, na grande maioria dos casos, devem levar em consideração esse parâmetro, já que o lenho juvenil possui características inferiores a do lenho adulto, e diferentes proporções de cada tipo de lenho vão interferir na qualidade e no uso da madeira. Para a realização do presente estudo, foram eleitas três árvores adultas, de fuste reto e cilíndrico, com DAP superior a 30 cm, localizadas na Encosta Superior do Nordeste do estado do Rio Grande do Sul. Foi retirado um disco por árvore, com aproximadamente 2 cm de espessura a 0,10 m de altura do tronco. De cada disco, retirou-se, com auxilio de uma serra-de-fita, uma bagueta central de 2,0 cm de largura, bem orientada no sentido radial, incluindo a medula no centro, dividiu-se então a bagueta em duas amostras "A" e "B". Dessas, sorteou-se uma, e separou-se apenas o lenho inicial de cada anel de crescimento para a maceração (método de Jeffrey) conforme descrito por Burger e Richter (1991). Mediram-se, primeiramente, com auxílio de um microscópio ótico com régua micrométrica, o comprimento, largura e diâmetro do lume individual de cem fibras no primeiro anel de crescimento (próximo à casca), e, posteriormente, definiram-se trinta fibras, por anel de crescimento, como estatisticamente suficiente para o ensaio. A espessura das paredes das fibras foi obtida pela metade da diferença do diâmetro da fibra e do lume. A segregação dos dois tipos de lenho foi definida pela variação radial (medula-casca) das características anatômicas (comprimento, diâmetro, largura do lume e espessura da parede das fibras) por meio de duas regressões lineares simples. Os resultados indicaram que o comprimento de fibra é a melhor característica para a definição do ano de segregação. Utilizando-se essa variável, determinou-se o ano de segregação dos lenhos juvenil-adulto em 16 anos. Por sua vez, os parâmetros anatômicos, diâmetro das fibras, largura do lume e espessura da parede das fibras mostraram-se inadequados, para a estimativa da idade de segregação, em conseqüência dos baixos coeficientes de determinação (R²), altos erros de estimativa (Sxy) e baixos valores para Razão F, observados nos modelos estatísticos
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Durabilidade natural da madeira de três espécies florestais em ensaios de campo.
'Universidad Federal de Santa Maria', 2010Co-Authors: Rafael Rodolfo De Melo, Gatto, Darci Alberto, Haselein, Clovis Roberto, Santini, Elio José, Stangerlin, Diego Martins, Susin FelipeAbstract:This work aimed to evaluate the natural durability of heartwood and sapwood of Luhea divaricata, Carya illinoinensis and Platanus x acerifolia. Test samples measuring 2.5 x 2.5 x 30.0 cm (radial x tangential x longitudinal) were placed in a pine forest stand and an open field. During a year, the samples were repeatedly weighed and evaluated by a rating system to determine mass loss and decay index, respectively. The results showed that regardless of species and type of wood, the forest environment is more favourable to decay than that of the open field. Despite the high correlation between mass loss and decay index, variations in the durability of wood were found between these parameters. The wood from the internal section of the log (sapwood) was the more affected. For mass loss, no significant variation was observed for the species analyzed, however, for the decay index Platanus x acerifolia was shown to be the most affected.Com o objetivo de avaliar a durabilidade natural da madeira, amostras de alburno e de cerne de Luehea divaricata (açoita-cavalo), Carya illinoinensis (nogueira-pecã) e Platanus x acerifolia (plátano), medindo 2,5 x 2,5 x 30,0 cm (radial x tangencial x longitudinal), foram submetidas a ensaios experimentais em um povoamento de Pinus e em campo aberto. Durante um ano, as amostras foram periodicamente pesadas e avaliadas pelo critério de notas, para determinar o percentual de perda de massa e índice de deterioração, respectivamente. Os resultados mostraram que, independente da espécie e do tipo de lenho, o ambiente dentro da floresta é mais favorável a deterioração da madeira do que fora dele. Apesar da elevada correlações entre a perda de massa e o índice de deterioração foram observadas variações na avaliação da durabilidade da madeira entre esses critérios. Para todas as espécies, a madeira proveniente do alburno foi a mais atacada. Para perda de massa não foi observada diferença entre as espécies avaliadas, entretanto, o índice de deterioração apontou o plátano como a mais atacada
Clovis Roberto Haselein - One of the best experts on this subject based on the ideXlab platform.
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Resistência ao impacto da madeira de nogueira-pecã em diferentes condições de umidade Impact strength of nogueira-pecã wood on different moisture conditions
Universidade Federal de Santa Maria, 2012Co-Authors: Rafael Beltrame, Clovis Roberto Haselein, Darci Alberto Gatto, Marilia Lazarotto, Bruno Dufau Mattos, Elio Jose SantiniAbstract:Os estudos de resistência da madeira ao impacto referem-se à eficiência com que este material absorve energia de um impacto e dissipa-a sem danos a sua estrutura. Dessa forma, o objetivo deste estudo foi avaliar a influência do teor de umidade na resistência ao impacto da madeira de nogueira-pecã (Carya illinoinensis). Para tanto, foram utilizadas árvores procedentes de duas regiões fisiográficas do estado do Rio Grande do Sul. Os corpos de prova, em condições de equilíbrio a 12% de umidade e saturados, foram submetidos ao impacto utilizando-se pêndulo de CHARPY, e avaliados quanto à resistência oferecida com a aplicação da carga nos planos tangencial e radial e posições de retirada (medula - casca) nas toras, para as duas regiões fisiográficas em cada condição de umidade. Para auxiliar na interpretação dos dados, determinou-se a massa específica aparente a 12% e saturada, trabalho absorvido, coeficiente de resiliência e a cota dinâmica. Pôde-se verificar, por meio dos resultados, que a madeira de nogueira-pecã é mais resistente ao impacto na condição saturada.The studies of wood impact strength refers to the efficiency of this material in absorb impact energy and dissipate it without structural damages. The present study aimed to evaluate the influence of moisture content on the impact strength of nogueira-pecã (Carya illinoinensis) wood. For this, trees from two physiographic regions of state of Rio Grande do Sul were used. The samples, stabilized at 12% of moisture content and in green conditions (saturated), were submitted to impact tests through a CHARPY pendulum, and were evaluated for the resistance to the application of loads in the tangential and radial sections, and in the positions of the log (pith-bark) for the two physiographic regions at each moisture condition. Moreover, the apparent specific gravity at 12% and in green conditions (saturated), the absorbed work, the resilience coefficient and the dynamic quote were determined. The main results showed that the nogueira-pecã wood is more resistant to the impact when it is in green conditions
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ESTIMATION OF AGE OF SEGREGATION OF JUVENILE AND MATURE Carya illinoinensis (Wangenh) K. Koch WOOD USING ANATOMICAL CHARACTERISTICS
Universidade Federal de Santa Maria, 2010Co-Authors: Darci Alberto Gatto, Clovis Roberto Haselein, Diego Martins Stangerlin, Leandro Calegari, Ediane Andréia Buligon, Rafael Rodolfo De Melo, Rômulo Trevisan, Elio Jose SantiniAbstract:Knowledge of the demarcation of juvenile and mature wood is essential both for wood technology and forest management. Thinning, in most cases, must take into account this parameter, as the juvenile wood has inferior characteristics compared to mature wood, and different proportions of each type of wood will affect the quality and the use of the wood. Thus, this study aimed to determine the age of maturation of the wood using anatomical characteristics of Carya illinoinensis (Wangenh) K. Koch wood, through the segregation of juvenile and mature wood. Three adult trees, of good trunk, with diameter greater than 30 cm DBH, were chosen from the region Encosta Superior do Nordeste in the State of the Rio Grande do Sul. From each tree, one disc was removed, with approximately 2 cm in thickness, at 0.10 m in height of the trunk. From each disc was removed a central portion of 2 cm in width, well oriented in the radial direction, including the pith in the center, and this central portion was divided into samples “A” and “B”. One of these two samples was selected for separation of the initial wood of each growth ring for maceration (Jeffrey method ). First, the length, width and diameter of the lumen of one hundred fibers were measured in the first ring (next to the bark) and later, thirty fibers were defined per growth ring as statistically sufficient for the assay. The thickness of the walls of the fiber was taken as the half of the difference of the diameter of the fiber and the lumen. The segregation of the two types of wood was defined by the radial variation (pith-bark) of the anatomical characteristics (length, diameter, width of the lumen and thickness of the wall of fibers), through two simple linear regressions. The results indicate that the fiber length is the best characteristic for the definition of the year of segregation. The age of segregation of juvenile-mature wood was defined as 16 years. In their turn, the anatomical parameters, diameter of fibers, width of the lumen and thickness of the wall of fibers were shown to be inadequate for estimating the age of segregation.
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ESTIMATIVA DA IDADE DE SEGREGAÇÃO DO LENHO JUVENIL E ADULTO DE Carya illinoinensis (Wangenh) K. Koch POR MEIO DE PARÂMETROS ANATÔMICOS DA MADEIRA
Universidade Federal de Santa Maria, 2010Co-Authors: Darci Alberto Gatto, Clovis Roberto Haselein, Diego Martins Stangerlin, Leandro Calegari, Ediane Andréia Buligon, Rafael Rodolfo De Melo, Rômulo Trevisan, Elio Jose SantiniAbstract:Knowledge of the demarcation of juvenile and mature wood is essential both for wood technology and forest management. Thinning, in most cases, must take into account this parameter, as the juvenile wood has inferior characteristics compared to mature wood, and different proportions of each type of wood will affect the quality and the use of the wood. Thus, this study aimed to determine the age of maturation of the wood using anatomical characteristics of Carya illinoinensis (Wangenh) K. Koch wood, through the segregation of juvenile and mature wood. Three adult trees, of good trunk, with diameter greater than 30 cm DBH, were chosen from the region Encosta Superior do Nordeste in the State of the Rio Grande do Sul. From each tree, one disc was removed, with approximately 2 cm in thickness, at 0.10 m in height of the trunk. From each disc was removed a central portion of 2 cm in width, well oriented in the radial direction, including the pith in the center, and this central portion was divided into samples "A" and "B". One of these two samples was selected for separation of the initial wood of each growth ring for maceration (Jeffrey method ). First, the length, width and diameter of the lumen of one hundred fibers were measured in the first ring (next to the bark) and later, thirty fibers were defined per growth ring as statistically sufficient for the assay. The thickness of the walls of the fiber was taken as the half of the difference of the diameter of the fiber and the lumen. The segregation of the two types of wood was defined by the radial variation (pith-bark) of the anatomical characteristics (length, diameter, width of the lumen and thickness of the wall of fibers), through two simple linear regressions. The results indicate that the fiber length is the best characteristic for the definition of the year of segregation. The age of segregation of juvenile-mature wood was defined as 16 years. In their turn, the anatomical parameters, diameter of fibers, width of the lumen and thickness of the wall of fibers were shown to be inadequate for estimating the age of segregation
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TECHNOLOGICAL CHARACTERISTICS OF THE WOOD OF Luehea divaricata, Carya illinoinensis AND Platanus x acerifolia WHEN SUBMITTED TO BENDING
Universidade Federal de Santa Maria, 2009Co-Authors: Darci Alberto Gatto, Clovis Roberto Haselein, Miguel Antao Durlo, Elio Jose Santini, Leandro Calegari, José Newton Cardoso Marchiori, Diego Martins StangerlinAbstract:This work was conducted with the purpose of investigating bending characteristics of the wood of Platanus x acerifolia (Ait.) Willd., Luehea divaricata Mart. et Zucc and Carya illinoinensis (Wangenh) K. Koch. Such species were collected from non-managed forests located in Depressão Central and Encosta Superior do Nordeste, Rio Grande do Sul, Brazil. Five representative adult trees from each species per studied area were cut down, corresponding to a total of thirty trees. From the trunk, a 2.5 m long log was taken and, afterwards, transported to a sawmill for processing. A central 8 cm thick plank was sawn, from which samples for bending were manufactured. The samples were conditioned in standard room to a moisture content of approximately 14%. Then, the samples were placed in boiling water during 35 minutes and bended in rays of 16 and 21cm. For the qualification of the bending defects, the methodology presented by Vorreiter (1958) was used. Results showed that the wood of Carya illinoinensis (Wangenh) K. Koch had the best bending characteristics when compared to the other two species, independently of the ray bending tested. It seems that the ring porosity, characteristic of the Carya illinoinensis wood, contributed to the result. On the other hand, the wood of Platanus x acerifolia (Ait.) Willd. and Luehea divaricata Mart. et Zucc, with diffuse porosity and larger parenchyma proportion, presented more defective pieces.
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caracteristicas tecnologicas das madeiras de luehea divaricata Carya illinoinensis e platanus x acerifolia quando submetidas ao vergamento
Ciencia Florestal, 2008Co-Authors: Darci Alberto Gatto, Clovis Roberto Haselein, Jose Niewton Cardoso Marchiori, Miguel Antao Durlo, Elio Jose Santini, Leandro Calegari, Diego Martins StangerlinAbstract:This work was conducted with the purpose of investigating bending characteristics of the wood of Platanus x acerifolia (Ait.) Willd., Luehea divaricata Mart. et Zucc and Carya illinoinensis (Wangenh) K. Koch. Such species were collected from non-managed forests located in Depressao Central and Encosta Superior do Nordeste, Rio Grande do Sul, Brazil. Five representative adult trees from each species per studied area were cut down, corresponding to a total of thirty trees. From the trunk, a 2.5 m long log was taken and, afterwards, transported to a sawmill for processing. A central 8 cm thick plank was sawn, from which samples for bending were manufactured. The samples were conditioned in standard room to a moisture content of approximately 14%. Then, the samples were placed in boiling water during 35 minutes and bended in rays of 16 and 21cm. For the qualification of the bending defects, the methodology presented by Vorreiter (1958) was used. Results showed that the wood of Carya illinoinensis (Wangenh) K. Koch had the best bending characteristics when compared to the other two species, independently of the ray bending tested. It seems that the ring porosity, characteristic of the Carya illinoinensis wood, contributed to the result. On the other hand, the wood of Platanus x acerifolia (Ait.) Willd. and Luehea divaricata Mart. et Zucc, with diffuse porosity and larger parenchyma proportion, presented more defective pieces.