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In relation to other materials such as concrete, plastic, steel and aluminum, wood has a number of advantages, such as beauty, high mechanical resistance to mass, good thermal insulation and easy workability. Still, wood presents environmental advantages when compared to other building materials (cement, concrete, steel and aluminum), beause it is recyclable, renewable, biodegradable and requires low energy needs for its processing. Taking so many advantages of the wooden use, it’s necessary to aim a rational use for this raw material, as an example, there are the physical and mechanical properties, which are important for the structural use of the species in the design of wood structures. This work aimed to characterize the wood species Clarisia racemosa (Oiticica-Amarela), objectifying its viable use for structural purposes. The tests to obtain the physical and mechanical properties were carried out according to the recommended established by Brazilian Standard ABNT NBR 7190 (1997), allowing the classification of such species in strength class C60 (hardwoods), as well as evaluating the possibility of estimation (linear, exponential, geometric and logarithmic models) of the physical and mechanical properties in function of the apparent density. The results obtained from the regression models implied the possibility of estimating only the mechanical property of compressive strength parallel to the fibers (fc0) as a function of the apparent density (ρap, 12%).

Wood is a material, when compared with other materials applied in civil construction, displays several advantages such an elevated mechanical strength when related with its apparent density. The wood manufacturing industry has great representativeness in the Brazilian economy however, the irrational consumption of determined species brought damages to the forest, causing extinction of some species and consequently, rising wood prices in market. The characterization of unknown wood species presents an alternative for a more rational exploration and expand wood use in structural purpose, enabling the use of this species determining its properties. The study aimed to characterize 3 physical properties and 12 mechanical properties of Angelim vermelho (Dinizia excelsa Ducke.) based on Brazilian Standard ABNT NBR 7190. Twelve models were used for each test, totalizing 180 experimental results. The analysis of variance (ANOVA) handling the regression models will be used to predict the strength and stiffness as function of apparent density. The results presented on tests demonstrated compatible performance with common wood species used in civil construction, considered high strength wood and with adequate use in this activity. According the regression models, only three properties were considered significant with apparent density estimation.

Residue generation causes significant environmental damages, mainly when there on technology for its treatment and several times end up discarded inappropriately. Several industries sectors have developed management programs aiming to destiny adequately solid residues produced on their activities. An alternative to solve this problem is the recycling process, which treats the residues as a potential matter to produce new products, focusing to reduce environmental impacts and inappropriate residue discard. In this context, ecological bricks emerge as a great opportunity to recycle, permitting residue incorporation. The present research analyzed compressive strength, retraction and water absorption on adobe bricks, made of soil-lime mixture and reinforced with Kraft paper fibers. Blocks were made with 7% lime content and with 0%, 8%, 10% e 12% fiber addiction. The results demonstrated that soil-lime-fiber blocks, with indicated lime content and fiber addiction, did not presented results that satisfy normative criteria to be used as a innovative material.

The development of the civil construction industry generates major problems, such as the production of construction waste. This complication is aggravated mainly in municipalities where there is no management and disposal policy, as it is the case of Sinop, Mato Grosso (MT), Brazil. A possible solution to this environmental problem in that municipality is the application of ground waste to sand fraction as stabilizer in order to increase resistance of the regional subgrade. The latter is characterized as having a low-bearing soil capacity. Furthermore, this strategy may allow for soothing of other problems, such as granular material extraction from the environment. This paper sought answers to improve the low-bearing soil capacity in Sinop, which was granulometrically and mechanically stabilized by having natural soil mixed with two percentages of construction waste: 25% and 50%, with two compaction energies: normal and intermediate. Samples were subjected to tests for characterization and resistence. Results show relevant improvement in handling material characteristics. Natural soil, characterized as A-4 TRB, from bad to poor subgrade performance, and 12.2% CBR, with blend in three CBR cases as well as expansion, conformed to be sub-base material (CBR > 20%). Additionally, in one of the cases, it conformed to be base material (CBR > 60%). However, even though material with good resistance and bearing capacity was obtained, it was not possible to reach conclusions on its technical feasibility due to grain size not fitting ABNT NBR 15115 specification.

The increasing solid residue generation throughout the years, with the civil construction industry being responsible for most of this production, causes serious environmental impacts, since major part of this residue are not discarded appropriately. In this context, the present study intended to analyze the residue management on some public constructions of Barra do Garcas City Hall, Brazilian state of Mato Grosso. For the analysis, it was carried out a checklist with 29 questions about waste management, based on Brazilian CONAMA Resolution 307/2002. Positive results were obtained for cleaning and organization on construction site and negative results for segregation residues and their destination. Also, a estimate of CCR production on some constructions and the costs to implement and operate a residue recycling plant in Barra do Garcas city. Suggestions for CCR management improvement on construction site were made.

Wood, a natural and sustainable resource, has been used by humankind for several purposes especially in construction and some manufacturing sectors. Due to predatory harvest of well-known wood species and in consequence, possible shortage of these essences, it is indispensable to characterize new wood species. This study intended to determine, under the requirements of Brazilian Code ABNT NBR 7190, the mechanical and properties of Cedroarana wood (Cedrelinga catenaeformis Ducke). Besides, with the analysis of variance (ANOVA), testing several regression models, it has hoped to estimate the values of strength and stiffness as a function of apparent density. Thirteen specimens were used for each test, totalizing 195 experimental results. The mechanical properties of Cedrelinga catenaeformis obtained demonstrated compatible performance with regular wood species used in temporary civil construction. According the regression models, only two properties were considered significant with apparent density estimation.

Civil Construction Industry impacts significantly the environment, being one of the most critic factors related to elevated production of Civil Construction Residue (CCR). Among CCR produced, the Kraft paper package acquires notoriety, due their large use on material packaging, such as Portland cement and lime, then, present a high production rate and offer contamination potential, lack of collection logistics and nearly any reuse. In this scenario, the study and development of alternative constructive materials which applies the sustainability concept and CCR recycling have acquired great relevance in the sector. It is highlighted the residue incorporation on masonry soil-cement blocks, due its block are not submitted to the sintering process. Then, the present research intend to study adobe blocks mechanical properties based on soil-cement reinforced with cellulose fibers obtained from Kraft paper recycling. The bricks were confectioned with 7% Portland cement content and with 0%, 8%, 10% e 12% Kraft paper fiber addition, being submitted to compressive strength test, water absorption test, durability test with wetting and drying and retraction analysis. It was verified the confectioned composites presented as a viable and interesting alternative on technical and environment range. All studied researches presented null retraction and compressive strength increase on cracked state, toughness increase and good performance about durability.

The study of pull out strength of glued in rods perpendicularly to the grain is presented. Three types of resin were used in order to evaluate their efficiency. Additionally, the effects of the variation of the moisture content and of the glue line thickness were considered. The beams were made of wood from Corymbia citriodora, (ρ12% = 1000 kg/m3) and Pinus oocarpa Shiede (ρ12% = 550 kg/m3). The wood specimens (four samples for each type of test) were seasoned to the expected moisture contents of 12, 15, 18 and 22%. The anchorage length of the glued in rods was 80 mm, the hole diameters were 7.5, 8.5, 9.5 and 10.5 mm and their respective glue line thickness, 0.6, 1.1, 1.6 and 2.1 mm. The deformed reinforcing bars used as rods, with the minimum yield strength of 500 MPa, had nominal diameter of 6.3 mm. The obtained results confirmed the assumption that type of resin, moisture content, glue line thickness are strength determining factors, while density is less than others. The results are presented in a comparative form. The failure modes are discussed and the need of a broad understanding of resin behavior on wood was emphasized.

Wood has been used by mankind for many years in many purposes specially in construction and manufacture. It is necessary to characterize unknown species as an alternative for human use due to predatory harvest of well-known wood species; in consequence, possible shortage of this wood. This study intended to determine, under the Brazilian Standard ABNT NBR 7190, the mechanical properties of Copaiba wood (Copaifera sp.), and with the analysis of variance (ANOVA), handling the regression models, predict the values of strength and stiffness as a function of apparent density. Twelve models were used for each test, totalizing 180 experimental results. The mechanical properties of Copaifera sp. presented on tests demonstrated compatible performance with common wood species used in civil construction. According the regression models, any properties were considered significant with apparent density estimation.

The three point bending test, according the Brazilian Standard ABNT NBR 7190, enables to identify the values of two wood properties: conventional modulus of elasticity and conventional strength on static bending test. With the results, this study aimed to perform a numerical simulation using the finite element software ABAQUS and the experimental results of three point bending test using Simarouba amara Aubl wood specie test proofs. Two analysis were performed, considering wood as elastoplastic material in the first and the second, considering only elastic material. From stress-strain diagrams results, it was observed the evaluation of modulus of elasticity on static bending test is not valid due to material non-linearity. A constitutive model was proposed for Simarouba amara Aubl. wood specie and for evaluation of modulus of elasticity on static bending. It was performed a comparative analysis between experimental results and the proposed constitutive model. These models showed their efficiency when evaluated the normal stress on proof test with demonstrated accuracy, allowing its use by wood structures designers.

Wood is a natural, renewable and abundant material in Brazilian territory. But its use in civil construction is still commonplace. When compared to materials such as steel and concrete, it has many advantages, such as its resistance to density ratio. Where it is possible to observe a high resistance, equivalent to concrete of high performance with a much smaller density. Due to the heterogeneity of the woods, very different behaviors may occur in response to the various requests. Thus, for a better use of its capacity is essential knowledge of its properties. Among them is impact strength in bending. Impact strength in bending knowledge is fundamental in structures that will be exposed to short-lived impact loads, such as bridges. But due to some factors this is not a mechanical property that is very accessible to most research centers. The objective of this research was to use linear, exponential, logarithmic and geometric regression models to verify if it is possible to obtain a relation between the resistance modulus in the static bending, which is more easily obtained, and the impact strength in bending values. Ten Brazilian wood species were selected and static bending and impact in bending tests were performed according to ABNT NBR 7190:1997. All tests were done in the Wood and Timber Structures Laboratory (LaMEM), in the Department of Structural Engineering of the Engineering School of Sao Carlos, University of Sao Paulo. According to the results and the statistical analysis performed, it was possible to conclude that the Strength in static bending does not seem to be a good estimator of the impact strength in bending of wood.

Wood is widely used in many sectors of civil construction as a structural material. Brazilian code ABNT NBR 7190:1997 Design of Timber Structures governs the method of project design as well as the characterization of wood for structural design. In this aspect the code considers wood as an orthoptic material, however is well known that the organic origin provides great anatomical complexity to its. This work aims to study the distribution of normal stresses in a Tauari wood beam subjected to the elastic regime, and to ascertain the current position of the Neutral Line during test. For this purpose, a four-point static bending test and subsequent compression and tension to the grain tests were performed to determine the modulus of elasticity and calculate the normal stresses by recording deformations and applying Hooke's Law. The data were statistically analyzed to define bests adjusts to Stress vs. Strain diagrams, and thus determine the location of the Neutral Line. It was verified that the position of the Neutral Line was a normal distribution variable, being located at 1,07cm above the geometric center of the board. Finally, the comparison between values of normal tension obtained experimentally and through the theoretical method was determined and similarities were verified in these data, being also plausible the theory for the calculation of the normal tensions of the wood beams, when it is in the elastic regime.

The wood is a material widely used for several purposes, especially in the construction industry. There are many factors that this is due, between them the versatility and abundant availability of the material. However, the intensive use of some species might cause shortages. The lack of information about the wood behavior when it is exposed to various conditions, as well as projects not supported by regulatory rules, may imply in its inappropriate use, compromising in the safety of the structure. In this context, it was proposed the elaboration of roofing structures projects with the following characteristics: lattice type buildings Howe (10° slope - cement tile); span of 8, 10, 12, 14, 16 and 18 meters (geometrical proportion, in design, surrounding a 1: 3); typology of the lateral side of the building openings - relations 1:1, 2:1, 6:1 and open (coverage of small dimensions’ support) preservative treatment. Then, was determined the ratio of the wood amount (m³) and the built area (in design) to woods of C20 and C30 classes, following the requirements of NBR 7190: 1997. Front of the analysis of results was evidenced that it is possible to use unconventional woods applied in triangle framework structure in big spans, obeying a well elaborated conception of project.

Timber is one of the oldest raw materials in construction, due to their availability worldwide, and the ease of using it. The majority of buildings in Brazil, until the Industrial Revolution, utilized this material as main input, rooting most of our cultural heritage in it. With the passage of time, as all materials, occurs the deterioration of these structural parts, where occasionally the partial replacement can solve the problem. This study aimed to analyze the relation between the amount of self-tapping screws and the rigidity product of composite mixed pieces of Eucalyptus sp and treated Pinus sp, simulating the rehabilitation of a structural piece in state of degradation, with the replacement of the degraded portion.

Uncontrolled and equivocal uses of well-known structural wood species have influenced shortage of these products on market of structural design. In order to raise awareness of the professionals of building construction about alternative wood species, a proposal is here discussed by employing these essences in footbridges. A case study is considered: a hyperestatic trussed arc with intermediate deck, parameters chosen based on local features of structure implementation. This project aims to reduce pressure on traditional species, evidencing alternative woods technical capacity, and improve accessibility in crossings over city streets. To provide greater durability to structure life, preservative treatment type has been set. Finally, by results, that it is possible to apply mean strength wood in large structures, requiring only right combination between structural staticity and wood properties.

The most commons woods used for production of medium density particleboard (MDP) are Eucalyptus and Pinus. The Cajueiro and Amescla wood are typical trees coming from the center-west of Brazil, from the States of Mato Grosso and Tocatins. These are medium density woods similar to Pinus sp, the Brazilian’s wood’s industries usually used these woods only as piece of wood for structures or furniture. The purpose of this research is to investigate, in a preliminary study, the possibility of MDP panel’s production using Cajueiro and Amescla wood species. The panels were produced under a pressure of 4 MPa for 10 minutes at 100°C, and it was produced a total of 12 MDP panels, 6 of Cajueiro and 6 of Amescla, with a thickness of 10mm, dimensions 250mm×250mm and 0.5 kg mass. For the bending modulus of elasticity, 2200 MPa were obtained for Cajueiro and 2700 MPa for Amescla, which are considered good values. The results can be considered satisfactory because it is a preliminary and unpublished study in the case of MDP panels manufactured with Cajueiro and Amescla wood species.

This research has the proposal create a simulator to valuate and simulate the capacity of a sugar factory, supporting the strategic decision making process. The process of creating simulator starts when processes are mapped and all most important variables are defined. After that it was necessary to transmit measured data through the calculations for spreadsheet, which in this case was used Excel (because it is a simple language and a common program). In sequence, several tests were performed to check results obtained by simulation. The results refer to the simulator reliability, with comparison of SIMULSUGAR results with simulation conducted in sector. Creating a table was necessary to demonstrate the accounting comparison between SIMULSUGAR results with simulation performed in the sector.

The development of standard methods and criteria for the stress grading of structural timber elements by non-destructive, fast and cheap bending tests, will allow producers, distributors and customers of such elements, have a better control of the marketed product. This paper analyzes the most suitable length of free span for stress grading of structural timbers, number of points to be assayed in each element, data precision and evaluation of cost of these tests for small business.

This research presents the assessment of historic structural systems timber roofs type "Hauff" of constructions existing in Pocos de Caldas, Minas Gerais, Brazil. The large timber structures originated with the engineering company "Hauff", whose production of timber structures contributed in great measure to the technological advance of the industry of construction engineering with wood in Brazil. Based on photographic by techniques of visual inspection (NDT) and descriptive documentation, this paper offers examples of timber roof structures that constitute most of type "Hauff" roof structural systems, such as, lamellar roof structure, sawn lumber nailed arch, plywood arch, shed truss roof, that were built between the years 40 and 60 in the city at Pocos de Caldas in Minas Gerais. The timber structures with "Hauff" were built in various regions of Brazil at that time.

Several factors suggest wood use in construction field and, among them, highlight mentioned material's versatility and availability, widely used in roof structures. In some situations, carpenters are responsible for implementing these structures and are almost never designed according to normative precepts. This study shows relation between timber volume and construction area (in plain view) with concrete roof structures and spans ranging from 8 to 14 meters, with bolted connections, relative to C30 strength class, from standard ABNT NBR 7190 recommendations. Based on these values, it is presented a comparison about consumption usually obtained by active technical professionals in Sinop - Mato Grosso State, Brazil, from a study case of a shed in Forest Park of Sinop. Results show a mean consumption of 0.025 m 3 /m 2 for the considered span. Thus, there was a 21% decrease in timber volume (span of 14m) and 50% in raw material (timber) coast when compared mentioned park structure. Covers projects were made with C30 species, about 30% less resistant than employed in the shed. In addition, there was a 50% reduction in pillars and foundations number compared to shed.

Wood is a renewable material, presenting wide use in building construction. For its better employability, it is necessary to perform physical and mechanical characterization of the several species available for application. In this respect, Brazilian Code ABNT NBR 7190:1997 - Timber Structures Design, in its Annex B, prescribes the proper tests and adds some relations between properties and strength classes for coniferous and dicotyledonous. The strength classes are function of characteristics values of strength in compression parallel to grain (fc0). However, density is a more easy-determination property and the cited Code presents the mean value of density for each strength class. Therefore, this research aimed to evaluate the possibility of inferring fc0 based on density obtained on tests of three Brazilian tropical wood species: Canafistula (Cassia ferruginea); Angelim araroba (Vataireopsis araroba) e Castelo (Gossypiospermum sp.). Statistical procedures shown it is possible to conclude that, in some cases, density is not a good estimator of fc0.

Shrinkage and coefficient of anisotropy are fundamental physical parameters in analysis of dimensional stability of timber structures members. In Brazil, properties of wood are obtained according to assumptions and calculation required by Annex B of ABNT NBR 7190: 1997 (Timber Structures Design). Among the physical properties, density appears as the easiest one to be experimentally obtained, defined by ratio between mass of the sample and its volume. To evaluate the possibility of estimating shrinkage (longitudinal, RL; radial, RR; tangential, RT; volumetric, RV; and coefficient of anisotropy, CA) of wood depending on density, this study aimed to test regression models (linear, exponential, logarithmic, geometric) using basic density (ρbas) and apparent density (ρ12) as independent variables. For this purpose, five wood species belonging to conifers: Pinus sp., Pinus oocarpa; and dicotyledonous: Parica (Schizolobium amazonicum), Jatoba (Hymenaea sp.) and Lyptus®, were employed. In all, 23 samples for Pinus sp.; 15 for Pinus oocarpa; 28 for Parica; 16 for Lyptus®; and 11 for Jatoba were produced, totaling 651 determinations. Results of analysis of variance for regression models indicated insignificance of the adjustments obtained by adopting densities as estimators of shrinkage and coefficient of anisotropy for this set of wood species. Only models involving basic density and apparent density were significant, wherein the optimal settings were from linear case, exhibiting coefficient of determination (R2) 91.72% (for softwoods) and 83.36% (for hardwoods).

Glued laminated timber is a structural engineered product that requires precision and strict quality control in its manufacture. For ensure that produced elements properties are in compliance with regulatory requirements, final product must be tested under laboratory conditions. Determining factors in final glulam pieces cost are the type and the quantity of adhesive used in structural elements manufacture. This study aimed to investigate, aided by three point static bending tests and variance analysis (ANOVA), influence of glue lines (3, 5, 7) and lamellae (4, 6, 8) on strength (MOR) and stiffness (MOE) properties of glulam beams manufactured with Pinus oocarpa (CCA treated) and bonded with Phenol Resorcinol resin (Cascophen RS-216-M). These beams presented nominal dimensions 90mm wide; 100mm height; and 1350mm length. For 100 mm fixed height, three beams configurations were tested (a) with four lamellae of 25 mm (3 glue lines); with 6 lamellae of 16,7 mm (5 glue lines) and 8 lamellae of 12.5 mm each (7glue lines), being fabricated 6 beams for experimental condition. In addition to investigating influence of glue lines and lamellae number, possibility of estimating MOE and MOR based on apparent density was also evaluated. ANOVA results showed no significance about glue lines number (or lamellae thickness) in strength and stiffness values, implying, for economic reasons, be configuration with four 25mm lamellae the best among tested beams. From regressions, apparent density was only significant in MOE estimating (R 2 = 46.90%), indicating not be possible to estimate the stiffness and strength values of the glued laminated timber evaluated by the apparent density.

The aim of this research is determining mechanical properties of Parica wood specie (Schizolobium amazonicum Herb) using structural and clear specimens, according to Brazilian standard ABNT NBR 7190 requirements. Parica wood specie in structural members, with moisture content of around 12%, were determined dynamic elasticity modulus (transverse vibration tests), static bending modulus (three point bending) and modulus of rupture in static bending test. In clear specimens, according to Brazilian standard were determined compression, shear, embedment and tension parallel to the grain, and the elasticity modulus in compression and tension parallel to the grain. It is concluded that the Parica wood specie present good strengths properties, although of low density, presenting potential for use in timber structures.

The knowledge about anisotropy of wood possibility more security design of structures and structural members designed. Therefore, there are little quantity of results knowledge about shrinkage and anisotropy coefficients of Wood species, motivating the development of new researches. The aim of research is evaluate the possibility of estimate the full shrinkage (radial; tangential; volumetric), anisotropy coefficient and shrinkage coefficient (radial; tangential; volumetric), using polynomial regression models (linear; quadratic; cubic) and exponential, by density of five Wood species (Cedro Doce [C20]; Canafistula [C30]; Angelim Araroba [C40]; Mandioqueira [C50]; Angelim Vermelho [C60]), properly classifieds in five strength classes for dicotyledonous according Brazilian Standard ABNT NBR 7190:1997. The better results were from tangential and volumetric retractions both using exponentials functions, justified by lower values of variation coefficients, with coefficients values of determination adjusted ranging from 51 and 54%. Even considered significant to the regressions for the tangential and volumetric shrinkage by analysis of variance, but with adjusted coefficients of determination lower than 70%, news researches should realized with other Wood species, enabling find general expressions for estimating such properties using the knowledge of the density.

Glued laminated timber (glulam) is an engineered product that requires manufacturing precision in all its stages. The finished product can only be tested in laboratory conditions; however, it is necessary to provide the quality control in production to ensure that glulam properties are appropriate to the product specified requirements in accordance with proper codes. This research aimed to evaluate the proposed trials conducted with combinations of Parica (Schizolobium amazonicum, a tropical wood species coming from a certificate reforestation area), three adhesives (polyurethane, phenol resorcinol formaldehyde, melamine formaldehyde) and two types of treatment (CCA, CCB). The shear strength and delamination test results of all the treated samples showed the good performance of Parica glulam, which can be used to indoor and outdoor applications.

In the last decades, the study of fracture mechanics has been increase as tool capable to analyze the mechanical strength for structures without the occurrence of failure. The presence of small cracks can reduce the structural strength of the component enabling, in some cases, the collapse of the structure under a lower stress than the structural ultimate strength. Currently, the use of numerical methodologies, as finite element method (FEM), that address the problem of fracture in structural components to representing the macroscopic regime of the structure has been also used becoming increasing. The goal of the article, through the analysis of fracture and grounds of FEM, determine the fracture growth for a polymeric material (epoxy resin). Through ASTM E399 were established experimental procedures for obtaining fracture toughness (GC), the mechanical fracture bending SE (B) testing was choose, for its simplicity of design and manufacture. Three different numerical models were used to analyze the behavior the material and the fracture process. The results obtained from the numerical simulation were close to the literature results, confirming the effectiveness of the numerical tool used in predicting fracture phenomena in the material and its evolution associated with the loads application.

Parica (Schizolobium amazonicum Herb.), is a native species from Amazon region, with very susceptible wood to xylophagous agents attacks. Therefore, to know the permeability of this species is information to define the chemical treatment suitable for the durability of this wood in use. For this study, it sawed wood from planted areas of the amazon region was used. It is possible to determine the permeability with the aid of proper equipment. The specimens, used in this research, were obtained randomly from pieces, 6 specimens for each one of the fluids tested: atmospheric air, distilled water and CCA chemical preservative. The value of atmospheric air permeability was 504.15 cm³/cm.atm.s with variation coefficient of 7.78%. For distilled water, the permeability and the variation coefficient were 10.84 cm³/cm.atm.s and 23.16%, respectively. Regarding the CCA, the permeability was 228.69 cm³/cm.atm.s and the variation coefficient 61.97%.

The design of timber structures, and other materials, must follow the procedures and methods of calculation of normative standards. Some normative documents in the design of timber structures adopt quite simple arithmetical relationships to relate wood properties in order to make it simple and quick evaluation of the behavior of structural elements, as is the specific case of Brazilian standard ABNT NBR 7190:1997, establishing a single relation for the shear (G) and the longitudinal (E) modulus of elasticity (E=G/20), which implies taking statistical equivalence to the values of the elastic moduli in the longitudinal-radial (GLR) and longitudinal-tangential (GLT) directions, which are important properties in relation to the requirements of structural projects. In this context, this study aimed to investigate, with the aid of four and three points static bending tests performed on the of dicotyledonous wood species grown in Brazil, the determination of the values of ELR, ELT, GLR and GLT to confirm the possibility of its equivalence (ELR and ELT, GLR and GLT), and for establishing correlations among them. The results of the hypothesis testing between the shear and longitudinal modulus of elasticity exhibited equivalent by species and simultaneously for all species, and the results of the linear regression model showed not possible to estimate the shear modulus of elasticity with knowledge of the longitudinal modulus of elasticity, and the optimal coefficient found by least squares method to the relation between the modulus of elasticity was equal to 35 (E=G/35), suggesting the need for an adjustment of the coefficient for this scale more safe wooden structures.

OSB panels were developed as a substitute for plywood. However, their properties in static bending, i.e. modulus of elasticity (MOE) and modulus of rupture (MOR) are often reduced. The aim of this study was to evaluate MOE and MOR of OSB manufactured with Pinus sp. and castor-oil based polyurethane resin, applying a wire mesh in order to improve those properties. Recommendations of normative document EN 310:1993 were obeyed. Results showed that mechanical properties considered are compatible with codes requirements and with values obtained by several authors in related literature. In static bending tests, the difference between parallel-to-grain MOE and MOR values of panels with and without wire mesh treatment was not significant. Statistical analysis reveals that the wire mesh pressing position does not affect MOE and MOR. However, these values are superior to those recommended, for OSB and plywood, by normative documents.

MDF in Brazil is an almost recent product, available in the market from the late '80s. The resin content appears as one of the factors that most influence the final properties of MDF panels. Identification of how these factors interact is very useful for improving performance and energy inputs, determining ideal resin content based on the desirable properties. This paper analyzes the most important properties of a MDF panel in the industry, in directions: perpendicular and parallel to the direction of production, thus verifying the homogeneity throughout the panel, according to EN 622-5, by determining the MOE and MOR in bending, draw perpendicular, swelling and water absorption. In the same way, it was analyzed if there is a direct relationship between the bending and tensile perpendicular to face properties. Results showed that the panels studied cannot be considered within the normative standards, despite having attended many of these requirements, for example, in presenting an MOE greater than the relevant standard. Through the analysis of variance, we observed the uniformity of properties in both directions studied. As a result of feedback from the wheel perpendicular and thickness swelling, can admit a bad distribution of the patch panel and a larger amount of paraffin, which was observed by the inconsistency between these properties. Through the low value in the analysis of R², we can say that there isn’t a correlation between the MOR in bending and tensile strength perpendicular.

The Carbon Fibre Composites (FRP) have long been used to increase the strength of the concrete structures. This happens because they provide a highly effective intervention without changing the geometry of the parts. In Brazil, the concrete are produced for various purposes, and everything depends on the trace set for the basic material constituents. The ability to repair and strengthen concrete structures already designed, this study aimed, with the aid of ABNT NBR 5739 standard and the analysis of variance (ANOVA), assess the strength of concrete in compression with low, medium and high strength (defined by the Brazilian standard) by including laminate carbon fiber composites. From laboratory tests and ANOVA, found efficiency of the reinforcement in all three types of concrete manufactured and greater efficiency in low strength concrete, justified by the lower tensile strength, which means striving responsible for bringing the specimens to failure.

Wood of Parica species (Schizolobium amazonicum) is highly susceptible to degradation by decay microorganisms. Due to its increasing production in the northern region of Brazil, about 85 thousand hectares, and later use both for structural purposes and for the furniture industry, the need of extending life of Parica wood applying chemical preservatives arises. One current alternative is the treatment by autoclave using CCB (Copper Chrome Boron). The aim of this study was to evaluate the influence of treatment with CCB in the properties: apparent density, parallel and perpendicular hardness to the grain, strength to shear and in the compression parallel to the grain of the Schizolobium amazonicum wood species, comparing the results with untreated wood. We observed that treatment with CCB did not change the properties of apparent density, shear strength, perpendicular hardness, strength and stiffness in compression parallel to the grain. For the hardness strength parallel to the grain was decreased in 28.9%.

Reference Abstract OSB (oriented strand boards) are wood based products that substitute plywood boards, usually used as structural elements, especially with part of formwork for reinforced concrete members as beams, slabs and columns. In this context, the stiffness properties are highly important. This study aimed to evaluate, with the aided of three points static bending test, the modulus of elasticity of OSB using recommendations of the European Standard EN 310:1993, combined with an alternative method of calculation based on the least square method. In this case, three displacement values are taking in account to stiffness determination, improving reliability on it. Results of the ANOVA indicated no statistical equivalence between moduli of elasticity obtained by the two methods of calculation. Modulus of elasticity of this technique proved to be 7% lower than the elastic modulus obtained by standard EN 310:1993, revealing be important the use of suggested approach.

This study aimed to investigate, based on three points static bending tests, the influence of ratio between length (L) and diameter (d) in structural round timber of Corymbia citriodora to determine the modulus of elasticity (MOE) using equations that do not consider shear influence in beam displacements. Non-destructive tests were carried out in 24 round pieces, medium length 750cm and average diameter 30 cm, moisture content around 12%. Modulus of elasticity for six different ratios (L/d) between length and diameter (9, 12, 15, 18, 21, 24) were determined, providing obtains six distinct values of MOE for each structural elements. Hypothesis tests results indicated equivalence of modulus of elasticity only to ratios (L/d) 24, 21 and 18. This implies that for proper use of the simplified equation to obtain MOE, based on static bending tests over structural round timber, it is necessary to respect L/h≥18 ratio.

This study aims to determine physical properties of particleboard made of sawmill waste, as a mix of several wood species, and two adhesives: urea-formaldehyde, usually employed in industry (even with drawbacks or formaldehyde emission during pressing) and FASTBOND ® , water based resin, still poorly referenced in literature. Sixteen panels have been produced, in four experimental conditions, defined by using two adhesives and a 12 mm thick limiter (or not). Variance analysis was adopted to evaluate influence of experimental conditions on physical properties of produced panels, manufactured in nominal dimensions 350x350mm; 10% resin related to particles mass (at 5% moisture); 3.5 MPa compaction pressure, temperature 130°C, in a 10 min cycle. Tests to determine density, moisture content, swelling and water absorption were carried out based on normative parameters of ABNT NBR 14810:2006. Results have been satisfactory to panels produced with urea-formaldehyde but those manufactured with polychloroprene based resin (FASTBOND

This paper focuses on the main characteristics of a Tree-Shaped Timber Structural System, or simply, Tree-Shaped. One of them is the complexity of its steel connections, responsible for the joint of bar elements, compounding a complex structural system, which requires the application of the CYPECAD software version 2007 to solve the calculations concerns. Its efficiency was confirmed by a variety of laboratory tests carried out with the whole structure. The Tree-Shaped is a timber structure that enables a large number of functional programs, residences, malls, sheds, hangars, etc. Originally it was conceived in Barcelona/Spain based on the well-known masterpiece "Sacred Family", whose author was Architect Antoni Gaudi I Conet (1852 - 1926). It was designed at the end of XIX Century and its construction is still not finished. Gaudi inverted the logical order of the gothic concepts, i.e, light weights below and heavy weight above. Based on this concept, he always had in mind the figure of a tree in nature. The Tree-Shaped follows the same idea, using timber pieces connected by steel plates. Theoretical and numerical analyses have shown its efficiency and lightness for use in timber structures and roofs.

This study aimed to evaluate the energy efficiency, thermal power and amount of volatiles released (CO2, CO and SO2) by three models of wood-metallic cookstoves into single-family residences in the city of Irati / PR, Brazil. All cookstoves had a low average energy efficiency fro m 2.9% ± 0.3 (stove 1), 2.6% ± 0.5 (stove 2) to 4.6% ± 0.2 (stove 3). The thermal power was 159.3 W ± 14.2 (stove 1), 142.7 W ± 39.2 (stove 2) and 176.5 W ± 21.7 (stove 3). It was observed a high pollutant levels of volatile compounds such as CO 34,9 Nm 3 /kg ± 3,1; 35,2 Nm 3 /kg ± 8,6 and 24,5 Nm 3 /kg ± 2,1; CO2 314,4 Nm 3 /kg ± 28,3; 316,5 Nm 3 /kg ± 77,0 and 220,9 Nm 3 / kg ± 19,0, lastly SO2 0,027 Nm 3 /kg ±0,0; 0,027 Nm 3 /kg ± 0,0 and 0,019 Nm 3 /kg ± 0,0, respectively fro m first to third stove. The results of the analysis of variance showed that the stove 3 showed to be the most efficient among the models investigated. In general, the obtained data indicate a low energy conversion and a potential health risk to the user due the release of to xic gases, such as carbon mono xide, present in the smo ke inside the house's kitchen.

Brazil Society of Automotive Engineers (SA E Aerodesign Co mpetition) proposes to engineering, physical sciences and aviation design student the challenge of construct an Un manned Aerial Veh icle (UA V). In addit ion, this event aims to promote the exchange and dissemination of aeronautical engineering techniques and knowledge. Among them, there is simu lation softwares based on finite element method. This study presents the mesh influence in the mechanical analysis performance with contact for a radio controlled aircraft wheel. For this study, were used the aircraft TKV 2011 wheel made with Alu minu m 7075-T651, with mechanical properties were obtained by AlumiCopper® manufacturer. The linear static analysis results were co mpared with number's variation of mesh elements. The mesh refinement, which requires a large computational effort and time required to perform the calculations, becomes unfeasible when the maximu m size o f the edge element is less than 0.25 mm, result in pro ximal values.

The study of the structural components of an aircraft such as landing gear, wheel and triquilha are elements that undergo constant changes, depending on the project requirement and efforts. A mong these mechanisms stands the wheel, because it is the element that makes the connection between aircraft and ground. Designed to withstand small di splacements and strains without losing its characteristics, is an element in wh ich studies with software using the Fin ite Element Method are present and important to better design component. The development of an Aeronautical Design, since its inception, detailed design and construction is a major challenge to the designer by the intense comp lexity of aerodynamic factors and dimensional parameters, integrated to a large mu ltid isciplinary. The present study aimed to use topological optimization processes present in Ansys ® software coupled with genetic algorith ms and statistical methods, software ModeFrontier®, analyze and get an optimal fo rm for the wheels used in aircraft cargo to Aerodesign SA E co mpetit ions. Bound methods allo wed a reduction of 40% co mpared to previous projects and found that the structural parameter Lane Width is that present the most influence on the mechanical performance of the aircraft.

This research aimed to present, with the aid of the three-points static bending, conducted nondestructively, analytical methodology to determine the longitudinal (E) and the shear modulus (G) of elasticity in round timber beams. The wood used was Eucalyptus clones. Were used three different values to the form factor coefficient of the circular cross section, allo wing evaluating the differences between the shear stiffness values obtained. The results of the analysis of variance indicated no statistical equivalence between the shear modulus of elasticity, revealing be significant the influence of the form factors used to determine the shear modulus of elasticity. The coefficient (λ) of the relat ionship between the modulus of elasticity (E=λ·G) obtained fro m the least squares method were equal to 118, revealing 5.9 higher than the relationship (E=20·G) p resented in the Brazilian standard ABNT NBR 7190:1997. It is emphasized that these results may be different for the same or different wood species, justifying the use of this methodology in each research developed.

Beams are structural elements commonly used in structure for construction designs. The use of wood as structural elements is very important because it is a material of renewable source, low density and satisfactory mechanical performance. When the wood surface is not properly treated, the structure can be destroyed not only by environmental conditions but also the attack of insects compro mising the design. This research aimed to evaluate the mechanical performance of the use of a particulate composite material (epo xy resin and structural Portland cement) as a way of reinforcing beams. The study of the mechanical performance of using this material in timber beams is essentially nu merical, based on the Finite Element Method, by using the static four points bending tests. The wood used in the simulation was the Eucalyptus grandis, and their mechanical properties were obtained fro m specialized literature in the area of timber structures. The results for d isplacements and stresses obtained fro m numerical analysis indicated that the co mposite material was able with successfully withstand the stresses caused by the loads, the same occurring with the wood, and the results of the hypothesis test for equivalence between meansrevelledtobeminor the influence ofPo isson's ratioon calculus of the displacements.

Abstrac t The wood is one of the most applicable materials in industrial activit ies due to its availability allied to its satisfactory mechanical p roperties, presenting a good strength/density relation. Its versatility is fundamental fo r the large expansion of its use on structure building. The explorat ion, init ially selective, turned to be selective and also predatory, what lead to a shortage, raising systematically the prices until the mo ment where it was not anymore probable to use it on the quantities registered until then. The solution was to define species, between more than 5.000 variet ies in AmazonicaTropical Forest, which could substitute the 100 co mmercially used ones. However, due to technical limitations, these species cannot be completely characterized, what leads to a misusing of timber, once its behaviour is not known completely when it is under mechanical stresses. This research presents some results of the characterizat ion of the following timber species: Canelao, Env ira Branca, Guaraja, Quaruba Rosinha and Breu Vermelho. These species are found close to Sinop (Mato Grosso - Brazil), and the results obtained reveal clearly the potential of each species under mechanical stresses, showing that some of them can be good substitutes to the commonly wood speciesused.

This paper presents a study of aircraft configuration TKV2012 that is more optimized as possible in all aspects of stage length, questions and restrictions established by the SAE Co mpetit ion BRAZIL Aero Design 2012. The analytical method for estimation of the aircraft aerodynamic coefficients was performed using the linear appro ximation to the theory of Multhopp. Design of Experiments (DOE) was used integrated into the genetic algorith m through the interface ModeFRONTIER®, version 4.3, the company Esteco®. We used the algorithm and Planning SOBOL MOGA II, with about 28 input variables, given the requirements: project report (containing plants and forecast payload), oral presentation, maximu m loaded weight, high structural efficiency, "accuracy" Predict ion Weight Loaded (Accuracy Project) and bonuses. The primary outcome variab le was the total score, since the goal was to maximize their. The results allowed to identify and optimize the d imensional parameters of the aircraft, as well as signaling the main factors that influence the total score, helping to define the configuration of the aircraft 2012.

This study aimed to investigate, with the aid of the Brazilian NBR 14810:2002 standard, the physical properties: bulk density and moisture and mechanical properties: strength flexural modulus and internal comp liance of part icleboards manufacture with bico mponent polyurethane resins derived fro m castor oil and Cambara, Canelinha and Cedrinho fibres. The factors investigated were: nominal density (0.80 g/cm3), no minal thickness (10mm), mo isture content of the particles (5%), percentage of resin (15%), t ime used in the pressing cycle (10min), hot pressing (100℃), pressing pressure (5MPa) and length of the particles (3 to 5mm), leading to a fu ll factorial design of 2 2 type, provid ing four different experimental conditions. The mechanical properties of both materials prepared showed higher values than the stipulated by the standard. Physical properties, only the density has overstepped the bounds set by the NBR 14810:2002, rating the particleboards produced as high density.

The use of numerical simu lations in the design of automotive components has contributed to reducing the design time, decreasing the prototypes costs and increasing reliability of the final product. In addition, the search for solutions of lo w cost and satisfactory performance is essential for the success of the product in the world market. Twist-beam suspensions are an examp le of this co mpetit ive environ ment. This solution presents a very satisfactory performance when applied to light vehicles and has an excellent relationship between cost / benefit in the automotive market. It is estimated that more than 90% of light vehicles manufactured in emergent countries use this type of suspension at the rear. Despite its acceptance in the automotive market there are few studies related to the twist -beam suspension, perhaps because of its simplicity and low cost design and ease of manufa cturing. Un like other types of suspension, the twist-beam has a flexib le torsion beam connecting the swing arms. The evaluation of the deformation of this flexib le element becomes essential to understand their kinemat ic behavior. Thus, the use of software based only on the rigid body dynamics is not suitable to analy ze this type of suspension. The main objective of this work was to evaluate through numerical simu lation based on finite element method, the influence of the torsion beam on the kinematic behavior of a twist-beam suspension. It was evaluated the influence of both the position and orientation of the torsion beam on the suspension, under symmetric and asymmetric loadings.

Timber is the oldest construction materials in the world, have been widely used in structures in addition to having a high longevity, if treated properly (maintenance). If this does not occur, the wood deteriorates due to the action of insects, fungi and other aggressive agents. There are several materials and techniques used to reinforce the damaged parts. This paper presents an experimental study ofEucalyptus grandis and Pinus elliiottiitimber beams rein forced with sisal fibres laminated composite materials. The co mposite material and the wood were prepared for testing. In order to simulate the defect, some parts were cracked. The study was to determine the maximu m load (rupture) applied on the timberin the conditions: without defect, with defect and without composite and with defect and with composite, aiming to verify the efficiency of the laminate as reinforcement in the wooden beams. The experimental results indicate the possible use of the laminated composite as reinforcement, presenting considerable increase in the maximu m strength supported by the timber when compared to unreinforced cracked condition, being more efficient for the Pinus elliiottii species.

In today's modern world the composite materials have been widely used not only for aerospace/aeronautics, but also automotive, sports and construction industries. The flexural strength of laminated composites depends on the characteristics of dispersive and matrix phases, considering the presence of tensile and co mpressive loadings. For this reason, the addition of particles into the matrix phase has been investigated to enhance its stiffness and consequently the elastic modulus of the composite. Th is work investigates a glassfibre co mposite reinforced with silicon carbide part icles. The following responses were evaluated: apparent density, water absorption, flexural strength, modulus of elasticity. The results were compared to those manufactured with no silicon carbide particles. It was observed that the silicon carbide particles provided the increase of the apparent density and flexu ral strength of the composites.