Technical report. Project 433/06 R3 (I) Sustainable Model for the Brazilian Wood Flooring Production Chain. Subproject:

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1 Technical report Project 433/06 R3 (I) Sustainable Model for the Brazilian Wood Flooring Production Chain Subproject: Evaluation of the bending properties, parallel compression and shear of 14 wood species of the mazon Prof. Dr. Geraldo Bortoletto Jr. (Coordinator) ntonio Pádua Radaeli Neto (cademic of Forestry) lex Canale (Laboratory ssistant) Summary Luiz de Queiroz College of griculture (ESLQ)/University of São Paulo (USP) 1 Introduction In construction, wood is used in various ways in temporary uses such as concrete forms, scaffolding and shoring. In a permanent way, is used in roof structures, in frames (doors and windows), the linings and floors (Zenid, 2009). The great expansion of construction, experienced in recent years and with excellent prospects of continuity, require the availability of a considerable amount of high wood density (ROCCO Lahar et al., 2010). In choosing the right wood for a particular use, one must consider which properties and their respective levels required so that the wood may have a satisfactory performance. The variety of wood species - and the breadth of its properties - existing in the mazon rainforest hampers the activities of sustainable forest exploitation and even more intensive marketing of timber potential of the forest, especially in markets traditionally supplied by a few species of wood. These circumstances suggest an approach to reduce the heterogeneity of the woods, by grouping or gathering in the same categories of common properties (Zenid, 2009). The incorporation of alternatives to the choice and specification of wood used in construction activities, as opposed to the environmental impacts caused by intensive and continuous use of a limited number of certain species proceedings species translates into important step towards the preservation and sustainability Brazilian forests (Zenid, 2009). Whereas there is a clear pressure on a small number of species of wood for use in construction, for which demand is increasing, and this brings difficulties for the effective sustainable management of our forests, in order to obtain grants and technical help to mitigate this problem, this study proposes the evaluation of bending properties parallel to the grain and 1

2 shear parallel to the 14 species of mazonian wood fiber compression and similarity grouping these into categories of common properties. 2 pplied methodology 2.1 Wood species and preparation of samples for testing The list of wood species studied in the project is presented in Table 1. Table 1: List of 14 species of mazon timber studied. Popular Name ngelim Vermelho Itaúba marela Cedrinho Cupiúba Pequiá ngelim da Mata Maparajuba Timborana Sucupira Preta Tachi Preto Tanibuca Mandioqueira Sapucaia Jarana marela Scientific Name Dinizia excelsa Ducke Mezilaurus itauba (Meisn) ex Mez Erisma unicatum Warm. Goupia glabra ubl. Caryocar villosum (ubl.) Pers. Hymenolobium excelsum Ducke Manilkara huberi (Ducke) Chevalier Piptadenia gonoacantha (Mart.) Bowdichia nitida Spruce ex Benth. Tachigali myrmecophila Ducke Terminalia amazonica (J.F. Gmel) Qualea paraensis Ducke Lecythis pisonis Cambess Lecythis poiteaui O. Berg Joists of wood with dimensions of 8.5 x 8.5 x 250 cm (03 per species) were placed in a natural drying to reach an average moisture content of 18%. Subsequently, the material was placed in a temperature-controlled room with temperature (22 ± 2 º C) and relative humidity (65 ± 5 %) controlled at the Laboratory of Mechanical Testing of Wood and Derivatives - LEMMD the Department of Forest Sciences ESLQ - USP, remaining well until they reached constant weight. fter constant mass, the joists were processed in a circular saw, resulting in parts with dimensions of 5 x 5 x 250 cm, from which we obtained the bodies of the specimen for the tests prescribed. Of these, 02 bodies -specimens for bending tests (a total of 06 per species), 02 for the compression tests (a total of 06 per species) and 04 for the shear tests ( in total, 12 were obtained by species). Half of the body-of - evidence for shear testing was obtained so that, during the test, they were subjected to stress in the radial plane (radial shear) and the other in the plane tangential to the growth rings (tangential shear). 2.2 Wood testing Testing of static bending (MOR - modulus of rupture and MOE - modulus of elasticity), compression parallel to grain (strength and MOE) and resistance to shear parallel to the fibers, were conducted according to the recommendations of BNT - Brazilian Standard NBR

3 (1997). ll values obtained by the tests were later corrected to standard moisture content of 12 %, also in accordance with the same standard. In the case of bending, adjustments were made to the recommendations of this standard: the dimensions of the bodies of the specimen were 5 x 5 x 75 cm and will (70 cm) between the back of the body-of - proof corresponding to 14 times its height. Such adjustments were needed due to the limitations on the length of beams available, and enable obtaining bodies of the test piece for the other tests, namely, compressive and shear. ll assays were performed at LEMMD in controlled temperature and humidity conditions, previously mentioned, and conducted in a universal testing machine instrumented with load cells to record the forces applied, LVDT (Linear Variable Differential Transformer) to record the displacements and deformations, and endowed with specific program for automatic acquisition of data generated. 2.3 Statistical nalysis The data obtained from the analysis of variance conducted at a 5% level of probability was performed and subsequently applied to the test Scott-Knott to carry out the grouping by the similarity of the species into categories of common properties. 3 Presentation of the data 3.1 Static Bending Table 2 shows the results of the static properties of the 14 wood species that have been studied mazon bending. Table 2 - verage values of MOR and MOE static bending strength of 14 wood species of the mazon Static Bending N MOR Standard Deviation MOE Standard Deviation Dinizia excelsa 6 163,3 a 1 18, a 1309 Mezilaurus itauba 6 114,9 c 20, b 722 Erisma unicatum 6 106,6 c 2, b 1147 Goupia glabra 6 106,0 c 26, b 3263 Caryocar villosum 6 104,4 c 22, b 3199 Hymenolobium excelsum 6 118,4 c 5, b 2043 Manilkara huberi 6 138,7 b 11, a 2331 Piptadenia gonoacantha 6 154,9 a 1, a 968 3

4 Bowdichia nítida 6 175,9 a 16, a 1222 Tachigali myrmecophila 6 132,5 b 8, a 1843 Terminalia amazônica 6 152,5 a 11, a 1573 Qualea paraensis 6 139,7 b 9, a 1404 Lecythis pisonis 6 137,1 b 34, b 3037 Lecythis poiteaui 6 135,7 b 14, a Within each column, means followed by same letter do not differ statistically at 5% probability of error s can be seen in Table 2, the results of the analysis of variance indicated that there were significant differences in mean MOR and MOE of the wood species. Thus, they do not constitute a single group, both as to the other one property evaluated. In the case of MOR species can be grouped into three distinct groups, as provided in Table 3, and in the case of MOE in two distinct groups, which can be seen in Table 4. Table 3 - Grouping of 14 species of wood from the mazon by similarity according to the static bending MOR Static Bending MOR Group 1 Dinizia excelsa 163,3 Piptadenia gonoacantha 154,9 Bowdichia nítida 175,9 Terminalia amazônica 152,5 Manilkara huberi 138,7 Tachigali myrmecophila 132,5 Qualea paraensis 139,7 B Lecythis pisonis 137,1 Lecythis poiteaui 135,7 Mezilaurus itauba 114,9 Erisma unicatum 106,6 C Goupia glabra 106,0 4

5 Caryocar villosum 104,4 Hymenolobium excelsum 118,4 Table 4 - Grouping of 14 species of wood from the mazon by similarity according to the static bending MOE Static Bending MOE Group 1 Dinizia excelsa Manilkara huberi Piptadenia gonoacantha Bowdichia nítida Tachigali myrmecophila Terminalia amazônica Qualea paraensis Lecythis poiteaui Mezilaurus itauba Erisma unicatum Goupia glabra Caryocar villosum B Hymenolobium excelsum Lecythis pisonis Parallel compression Table 5 shows the results of the parallel properties of the 14 wood species that have been studied mazon compression. 5

6 Table 5 - Mean values of strength and MOE compression parallel to 14 fibers wood species of the mazon Compression Parallel to the Grain N Resistance Standard Deviation MOE Standard Deviation Dinizia excelsa 6 86,3 a 1 5, a 3290 Mezilaurus itauba 6 63,9 c 5, a 7255 Erisma unicatum 6 52,9 d 5, b 2862 Goupia glabra 6 61,0 c 9, b 3433 Caryocar villosum 6 56,9 d 8, b 4531 Hymenolobium excelsum 6 57,0 d 3, b 4087 Manilkara huberi 6 68,1 c 5, a 5858 Piptadenia gonoacantha 6 73,8 b 2, b 2465 Bowdichia nítida 6 85,6 a 4, a 4422 Tachigali myrmecophila 6 62,2 c 2, a 4835 Terminalia amazonica 6 70,5 c 7, a 7175 Qualea paraensis 6 62,6 c 8, a 3423 Lecythis pisonis 6 68,8 c 3, b 5193 Lecythis poiteaui 6 65,7 c 4, a Within each column, means followed by same letter do not differ statistically at 5% probability of error s can be seen in Table 5, the results of the analysis of variance indicated that there were significant differences in mean strength and MOE between the wood species. Thus, they do not constitute a single group, both as to the other one property evaluated. In case of resistance the species can be grouped into four distinct groups, as provided in Table 6, and in the case of MOE in two distinct groups, which can be seen in Table 7. Table 6 - Grouping of 14 species of wood from the mazon by similarity under the resistance to compression parallel to grain Compression Parallel to the Grain Resistance Group 1 6

7 Dinizia excelsa 86,3 Bowdichia nítida 85,6 Piptadenia gonoacantha 73,8 B Mezilaurus itauba 63,9 Goupia glabra 61,0 Manilkara huberi 68,1 Tachigali myrmecophila 62,2 Terminalia amazônica 70,5 C Qualea paraensis 62,6 Lecythis pisonis 68,8 Lecythis poiteaui 65,7 Erisma unicatum 52,9 Caryocar villosum 56,9 D Hymenolobium excelsum 57,0 Table 7 - Grouping of 14 species of wood from the mazon by similarity according to the MOE to compression parallel to grain Compression Parallel to the Grain MOE Group 1 Dinizia excelsa Mezilaurus itauba Manilkara huberi Bowdichia nítida Tachigali myrmecophila Terminalia amazônica Qualea paraensis Lecythis poiteaui Erisma unicatum Goupia glabra B Caryocar villosum

8 Hymenolobium excelsum Piptadenia gonoacantha Lecythis pisonis Shear Table 8 presents the results of the shear property of the 14 species of wood from the mazon that have been studied. Table 8 - Mean values of shear strength to the fiber 14 wood species of the mazon Shear parallel to the grain N Resistance Standard Deviation Dinizia excelsa 12 14,3 a 1 2,1 Mezilaurus itauba 12 11,2 b 1,5 Erisma unicatum 12 7,4 c 1,6 Goupia glabra 12 11,6 b 1,5 Caryocar villosum 12 14,1 a 2,6 Hymenolobium excelsum 12 11,1b 0,7 Manilkara huberi 12 12,7 a 1,6 Piptadenia gonoacantha 12 15,3 a 1,9 Bowdichia nítida 12 15,1 a 2,6 Tachigali myrmecophila 12 13,8 a 1,6 Terminalia amazônica 12 14,0 a 1,8 Qualea paraensis 12 13,5 a 1,5 Lecythis pisonis 12 14,6 a 1,9 Lecythis poiteaui 12 15,3 a 2,0 1 Within the column, means followed by same letter do not differ statistically at 5% probability of error s can be seen in Table 8, the results of the analysis of variance indicated that there were significant differences in mean shear strength between the wood species. Thus, they do not constitute a single group assessed for this property. ccording to the shear strength, the species can be grouped into three distinct groups, as can be seen in Table 9. Table 9 - Grouping of 14 species of wood from the mazon by similarity second shear strength Shear parallel to the grain Resistance Dinizia excelsa 14,3 Caryocar villosum 14,1 Manilkara huberi 12,7 Piptadenia gonoacantha 15,3 Group 1 8

9 Bowdichia nítida 15,1 Tachigali myrmecophila 13,8 Terminalia amazônica 14,0 Qualea paraensis 13,5 Lecythis pisonis 14,6 Lecythis poiteaui 15,3 Mezilaurus itauba 11,2 Goupia glabra 11,6 B Hymenolobium excelsum 11,1 Erisma unicatum 7,4 C 4 Conclusions There were significant differences in the mean values of all properties valued between 14 species of mazon timber studied. Thus, the set of all these species of wood is not a single group. It was possible to submit to reverse split wood species by similarity according to each one of the properties: a) for the bending MOR 03 distinct groups ( = 4 species, B = 5 and C = 5) were established in descending order of average values. In the case of the MOE 02 distinct groups ( = 8 and B = 6 species) have been established; b) for the resistor 04 to the parallel compression groups (species = 2, B = 1, C = 8 and D = 3) were established. In the case of the MOE 02 distinct groups ( = 8 and B = 6 species) have been established; c) for the shear strength 03 groups (species = 10, B = 3 and C = 1) were established. The wood species belonging to the same specific group (, for example), according to a particular property among the evaluated (static bending MOE, for instance), can be used without distinction between them because they are similar. Bibliography SSOCIÇÃO BRSILEIR DE NORMS TÉCNICS. BNT NBR 7190: Projeto de estruturas de madeira. Rio de Janeiro, Brasil, Rocco Lahr, F..; Chahud, E.; Fernandes, R..; Teixeira, R.S. Influência da densidade na dureza paralela e na dureza normal às fibras para algumas espécies tropicais brasileiras. Scientia Forestalis, n. 86, Zenid, G.J. Madeira: uso sustentável na construção civil. São Paulo: IPT: SVM,