COMPARISON BETWEEN TEST METHODS TO DETERMINE WOOD EMBEDMENT STRENGTH PARALLEL TO THE GRAIN

ABSTRACT This study compares the test methods according to the ABNT NBR 7190:1997, EN 383:2007, ASTM D5764:2007, EUROCODE 5:2004, NDS:2001 standards in order to provide support to establish a new test method for determining the embedment strength of wood parallel to the grain. Parallel-to-grain tests were carried out for six wood species (Schizolobium amazonicum; Pinus elliottii; Pinus oocarpa; Hymenaea spp.; Lyptus(r): hybrid Eucalyptus grandis and Eucalyptus urophylla, and Goupia glabra) using four diameters (8 mm, 10 mm, 12 mm and 16 mm) for the metal pin fasteners (bolts). The experimental results obtained according to the EN 383:2007 standard were closer to the specific values for the metal-dowel connections design used by ABNT NBR 7190:1997, which are considered equal compression parallel to the grain. The use of maximum embedment force or the force causing displacement of 5 mm between the bolt and the test-piece as criteria for determining embedment strength for EN 383:2007 appears to be more appropriate than the criteria used by the Brazilian and American Standards.

Download Full-text

Resistência da madeira ao embutimento perpendicular às fibras: comparação de métodos de ensaio

Ambiente Construído ◽

10.1590/s1678-86212019000400349 ◽

2019 ◽

Vol 19 (4) ◽

pp. 175-181 ◽

Cited By ~ 1

Author(s):

Diego Henrique de Almeida ◽

Antonio Alves Dias

Keyword(s):

Eucalyptus Grandis ◽

Pinus Elliottii ◽

Eucalyptus Urophylla ◽

Pinus Oocarpa

Resumo As ligações em estruturas de madeira são os pontos com maiores concentrações de tensões. Para o dimensionamento de ligações por pinos metálicos, dois parâmetros são utilizados: a resistência ao escoamento do aço e a resistência da madeira ao embutimento. O objetivo deste trabalho foi comparar métodos de ensaio e critérios de dimensionamento de documentos normativos (NBR 7190, EN 383, ASTM D-5764, EUROCODE 5 e NDS) para a determinação da resistência da madeira ao embutimento na direção perpendicular às fibras. Foram utilizadas seis espécies de madeira(Schizolobium amazonicum, Pinus elliottii var. elliottii, Pinus oocarpa Shiede, Hymenaea sp, Lyptus (Eucalyptus grandis/Eucalyptus urophylla) e Goupia glabra) e quatro diâmetros (8 mm, 10 mm, 12 mm e 16 mm) para os pinos metálicos nos testes. Em todos os casos observaram-se maiores valores médios da resistência da madeira ao embutimento determinados pelo método EN 383, sendo que em nenhum dos ensaios realizados, de acordo com essa norma, foi atingido o limite de 5 mm de deslocamento entre o pino metálico e a peça de madeira. Os resultados experimentais obtidos nesse caso tiveram boa concordância com os valores calculados pelos critérios da NBR 7190. Não foi possível realizar os testes usando o método de ensaio da norma NBR 7190, devido à dificuldade de obter as dimensões requeridas para os corpos de prova na direção perpendicular às fibras.

Download Full-text

Eucalypt Clonal Hybrid Influences the Carbon Amount of Below-Ground Biomass in Oxisol, Brazil

Environmental Sciences Proceedings ◽

10.3390/iecf2020-07868 ◽

2020 ◽

Vol 3 (1) ◽

pp. 53

Author(s):

Grasiele Dick ◽

Humberto J. Eufrade-Junior ◽

Mauro V. Schumacher ◽

Gileno B. Azevedo ◽

Saulo P. S. Guerra

Keyword(s):

Carbon Concentration ◽

Eucalyptus Grandis ◽

Eucalyptus Camaldulensis ◽

Eucalyptus Urophylla ◽

Ground Biomass ◽

Homogeneity Of Variances ◽

Below Ground ◽

Hybrid Eucalyptus ◽

Carbon Determination ◽

Hybrid Clones

The objective of this study was to evaluate whether there is an influence of different clonal hybrids of Eucalyptus urophylla on the carbon concentration and amount in below-ground biomass in trees cultivated in Oxisol, Brazil. Stumps and roots of three different eucalypt hybrid clones, AEC 0144, AEC 0223, and VM01, were selected, weighed immediately after being removed from the ground, and sampled for carbon determination and moisture content at the laboratory. The Shapiro-Wilk and Bartlett tests were used to evaluate data distribution and the homogeneity of variances, respectively. Analysis of variance (ANOVA) complemented by the Scott-Knott test was used to evaluate the effects of specie/hybrid on the below-ground biomass (dry matter) and carbon amount per stump. The hybrid type of Eucalyptus urophylla does not influence the carbon concentration; however, there is a difference in below-ground biomass production and carbon amount with it being higher for Eucalyptus urophylla × Eucalyptus camaldulensis when compared to the species Eucalyptus urophylla and hybrid Eucalyptus urophylla × Eucalyptus grandis.

Download Full-text

Dynamics of initial spacing on the diameter of hybrid Eucalyptus grandis x Eucalyptus urophylla in a systematic design

Australian Journal of Crop Science ◽

10.21475/ajcs.21.15.03.p2935 ◽

2021 ◽

pp. 422-430

Author(s):

Mirella Basileu de Oliveira Lima ◽

Mauro Eloi Nappo ◽

Kálita Luis Soares ◽

Renato Vinícius Oliveira Castro ◽

Eder Pereira Miguel ◽

...

Keyword(s):

Eucalyptus Grandis ◽

Planting Density ◽

Diameter Distribution ◽

Eucalyptus Urophylla ◽

Central Brazil ◽

Kolmogorov Smirnov ◽

Diameter Structure ◽

Initial Spacing ◽

Hybrid Eucalyptus

We evaluated the effect of initial spacing on the distribution of Eucalyptus grandis x Eucalyptus urophylla tree diameters in a Nelder wheel design. The study area was in west-central Brazil. A Nelder wheel design with three repetitions was used. This design provides 432 planting spots per plot/repetition. Planting density varied from 0.50 m² to 41.25 m². The diameter at breast height was measured for all plants every four months until 36 months of age, totaling eight measurements. The description of the diameter distribution was developed by fitting probability density functions for each spacing and age. The quality of fit was evaluated using the root mean square error percentage, Pearson’s correlation coefficient, and the Kolmogorov-Smirnov test (α < 0.05). The spacings up to 1.17 m² must be harvested in less than two years, since it is noted that in the third year the increment in diameter is static and the mortality rate increases. The spacing highly affects the diameter structure of the population, impelling the forester to consider different uses for the wood. For wood requiring larger diameters, spacing above 8.69 m² per tree is recommended

Download Full-text

Procedures for theoretical redistribution of diameters in eucalyptus stands

CERNE ◽

10.1590/s0104-77602010000100008 ◽

2010 ◽

Vol 16 (1) ◽

pp. 68-76 ◽

Cited By ~ 2

Author(s):

Thelma Shirlen Soares ◽

Hélio Garcia Leite ◽

Carlos Pedro Boechat Soares ◽

Antônio Bartolomeu do Vale

Keyword(s):

Probability Density Function ◽

Probability Density ◽

Density Function ◽

Eucalyptus Grandis ◽

Distribution Model ◽

Diameter Distribution ◽

Eucalyptus Urophylla ◽

Traditional Procedure ◽

Hybrid Eucalyptus ◽

Invariant Procedure

This study aimed to evaluate the application of a procedure referred to as step invariant for theoretical redistribution of diameters by class in a diameter distribution model, using the Weibull probability density function. Data from the first rotation of hybrid eucalyptus stands (Eucalyptus grandis x Eucalyptus urophylla) planted with spacings of 3 x 2 m, located in northeastern Bahia state were used. Measurements were taken annually with measurement age ranging between 25 and 89 months. The step invariant procedure provided satisfactory results in comparison to the traditional procedure, being therefore recommended for future applications due to its unbiased results and ease of fit.

Download Full-text

Organogenesis and transient genetic transformation of the hybrid Eucalyptus grandis × Eucalyptus urophylla

Scientia Agricola ◽

10.1590/s0103-90162011000200016 ◽

2011 ◽

Vol 68 (2) ◽

pp. 246-251 ◽

Cited By ~ 9

Author(s):

Giovana Bomfim de Alcantara ◽

João Carlos Bespalhok Filho ◽

Marguerite Quoirin

Keyword(s):

Genetic Transformation ◽

Culture Media ◽

Eucalyptus Grandis ◽

Leaf Explants ◽

Induction Medium ◽

Eucalyptus Urophylla ◽

Uida Gene ◽

Factors Affecting ◽

Bud Induction ◽

Hybrid Eucalyptus

The hybrid Eucalyptus grandis x Eucalyptus urophylla presents high levels of productivity and potential for use in paper, cellulose and fiber industries. The bud organogenesis from leaf explants of two clones of E. grandis × E. urophylla was studied in order to verify the effect of several factors: subculture duration on multiplication medium, type of explants, entire and half leaves: basal and apical portions, and duration of the culture on a regeneration medium. Differences in organogenic capacity of the two clones tested were observed. The explant most recommended for organogenesis is the basal section of the leaf collected from shoot clusters subcultured every 17 days. Moreover, the leaf explants must be transferred to a fresh bud induction medium every five days. This study also aimed at evaluating factors affecting the genetic transformation of leaf explants with the uidA gene, via co-cultivation with Agrobacterium tumefaciens, such as the pre-culture of the explants on a specific medium, the duration of their co-culture with the bacteria and the addition of acetosyringone to the culture media. The best conditions for the expression of the uidA gene were two days of pre-culture of the leaf tissues, three days of co-culture with the bacteria and the addition of acetosyringone in pre- and co-culture media.

Download Full-text

Propriedades de chapas tipo OSB, fabricadas com partículas acetiladas de madeiras de Eucalyptus grandis, Eucalyptus urophylla, Eucalyptus cloeziana e Pinus elliottii

Revista Árvore ◽

10.1590/s0100-67622006000400020 ◽

2006 ◽

Vol 30 (4) ◽

pp. 659-667 ◽

Cited By ~ 7

Author(s):

Carla Priscilla Távora Cabral ◽

Benedito Rocha Vital ◽

Ricardo Marius Della Lucia ◽

Alexandre Santos Pimenta ◽

Carlos Pedro Boechat Soares ◽

...

Keyword(s):

Eucalyptus Grandis ◽

Pinus Elliottii ◽

Minas Gerais ◽

Eucalyptus Urophylla ◽

Eucalyptus Cloeziana ◽

E 32

Este trabalho teve como objetivo avaliar as propriedades de chapas de 0riented Strand Board (OSB), fabricadas com flocos de madeira de Eucalyptus grandis, Eucalyptus urophylla e Eucalyptus cloeziana e oriundas dos Municípios de Ponte Alta e Três Marias, no Estado de Minas Gerais. As massas específicas básicas das três espécies de eucaliptos das duas regiões foram, respectivamente: Ponte Alta (0,55; 0,61; e 0,70 g/cm³) e Três Márias (0,56; 0,58; e 0,69 g/cm³). Quando necessário, para manter as massas específicas das chapas próximas de 0,70 g/cm³ foram acrescentadas às partículas de madeira de eucalipto partículas de madeira de Pinus elliottii, oriundo da cidade de Viçosa, com massa específica de 0,45 g/cm³. Os flocos foram gerados nas dimensões médias de 90,00 x 20,00 x 0,46 mm. O adesivo utilizado foi o fenol-formaldeído, na proporção de 8% de sólidos, em relação à massa seca de partículas. Parte dos flocos de eucaliptos foram acetilados. As chapas foram prensadas à temperatura de 170 °C e 32 kgf/cm² de pressão. As propriedades das chapas foram determinadas segundo as normas da ABNT NBR 14810-3 (2002) e ASTM-D 1037 (1991). Os resultados foram comparados utilizando-se as normas ANSI/A - 208.1 (1993) e CSA 0437-93 (1993). As chapas contendo partículas acetiladas foram mais estáveis e adsorveram menos umidade. Na tração perpendicular, observou-se que as chapas contendo 100% de flocos acetilados apresentaram resultados inferiores ao estipulado pela norma CSA O437-0/93 (1993). A resistência ao arrancamento de parafuso, módulo de ruptura (paralelo e perpendicular) e compressão longitudinal (perpendicular), foi reduzida pela acetilação nas chapas contendo 100% dos flocos acetilados. As espécies que apresentaram, numericamente, as maiores médias para resistência mecânica foram: Eucalyptus grandis não acetilado (dureza Janka) e Eucalyptus cloeziana misturado com Pinus sp (módulo de ruptura). Somente a resistência à compressão longitudinal foi afetada pela região de origem da madeira. Os painéis fabricados com madeira de Eucalyptus urophylla, oriunda do Município de Três Marias, tiveram médias inferiores aos das chapas feitas com a mesma espécie, porém oriundas do Município do Rio Doce.

Download Full-text

THERMAL DEGRADATION AND MORPHOLOGICAL ASPECTS OF FOUR WOOD SPECIES USED IN LUMBER INDUSTRY

Revista Árvore ◽

10.1590/0100-67622016000500018 ◽

2016 ◽

Vol 40 (5) ◽

pp. 941-948 ◽

Cited By ~ 10

Author(s):

Matheus Poletto

Keyword(s):

Thermal Degradation ◽

Wood Species ◽

Wood Fiber ◽

Eucalyptus Grandis ◽

Fiber Surface ◽

Pinus Elliottii ◽

Degradation Process ◽

Lumber Industry ◽

Scanning Calorimetry ◽

Morphological Aspects

ABSTRACT The aim of this work was characterize four wood waste samples from lumber industry in order to obtain previous information about structure and properties of wood before use it as a biofuel or as reinforcement in composite formulations. The influence of wood components on the thermal degradation stability of different wood species has been investigated using thermogravimetry, differential scanning calorimetry and scanning electron microscopy. Four wood species, Eucalyptus grandis (EUG), Pinus elliottii (PIE), Dipteryx odorata (DIP) and Mezilaurus itauba (ITA), were used in this study. The results showed that higher extractives contents may form a thin film on the wood fiber surface which can accelerate the degradation process and reduce the wood thermal stability

Download Full-text

An evaluation of ECT sample height for small flute board grades and Box Manufacturer’s Certification compliance

TAPPI Journal ◽

10.32964/tj8.6.24 ◽

2009 ◽

Vol 8 (6) ◽

pp. 24-28

Author(s):

CORY JAY WILSON ◽

BENJAMIN FRANK

Keyword(s):

Compressive Strength ◽

Compressive Load ◽

Test Sample ◽

Test Methods ◽

Test Method ◽

Initial Development ◽

Sample Height ◽

Relationship Of ◽

The Relationship ◽

Corrugated Fiberboard

TAPPI test T811 is the specified method to ascertain ECT relative to box manufacturer’s certification compliance of corrugated fiberboard under Rule 41/ Alternate Item 222. T811 test sample heights were derived from typical board constructions at the time of the test method’s initial development. New, smaller flute sizes have since been developed, and the use of lighter weight boards has become more common. The T811 test method includes sample specifications for typical A-flute, B-flute, and C-flute singlewall (and doublewall and triplewall) structures, but not for newer thinner E-flute or F-flute structures. This research explores the relationship of ECT sample height to measured compressive load, in an effort to determine valid E-flute and F-flute ECT sample heights for use with the T811 method. Through this process, it identifies challenges present in our use of current ECT test methods as a measure of intrinsic compressive strength for smaller flute structures. The data does not support the use of TAPPI T 811 for ECT measurement for E and F flute structures, and demonstrates inconsistencies with current height specifi-cations for some lightweight B flute.

Download Full-text