Despite the sectoral initiatives, the construction industry faces difficulties in incorporating effective environmental impact control systems in construction sites. Most of the instruments have been adopting a qualitative approach to environmental issues, with few cases of a quantitative approach. This article introduces a quantitative method for predicting environmental aspects and impacts during the construction of residential buildings, through the integration between environmental indicators and construction cost bases. The methodology was based on the analysis of the relationships among activities, aspects and environmental impacts considered in EU Eco-Management and Audit Scheme (EMAS) for the development of the method and its mathematical representation. A case study was carried out to evaluate the method using the bill of quantities (BOQ) from two residential construction sites to measure their environmental aspects. The results suggest the usefulness of the method in the decision-making process on the allocation of control systems and, in some cases, recommending the execution of off-site services to reduce the impacts on the site's neighborhood. Additionally, the method proved to be easy to apply to evaluate construction sites, as well as flexible to incorporate other activities, adapting to the demand of builders and municipalities to reduce the environmental impacts of construction sites.

The wood industry is known for being among the biggest resource consumers, having a relatively low yield. The wood furniture industry as part of the wood industry also remains a big generator of residues and a big consumer of resources. Diverse solutions and technologies have been developed to deal with the residues generated, but those technologies are mostly applied at the end of the production chain with limited results. Cleaner production represents a program based on continuous strategies applied to a more sustainable use of materials and energy, minimizing waste and pollution. This paper presents a case study of a cleaner production program developed in a small furniture industry in Salvador de Bahia, Brazil, applying the concepts of cleaner production with parameters of ecodesign developed for the furniture industry. The object of study was the production of a wooden chair made from eucalyptus wood. The application of the cleaner production program and ecodesign parameters allowed a detailed characterization of the waste, resulting in opportunities for a reduction of the use of raw material by 30%, a reduction in waste by 49% and allowing a reduction in energy by 36% due to simplification of the productive process. Among the strategies applied were reshaping pieces, redesigning, and the substitution of materials. The results suggest that despite the existence of more complex environmental methods and approaches, the application of cleaner production plus ecodesign parameters could be more achievable for micro and small furniture industries.

-Creep is a phenomenon that can occur in wooden structures since wood is a viscoelastic material. Creep may change the purely elastic parameters determined in wood characterization initial tests, as its behavior depends on the rheology of the material, even under a constant stress level. Mathematically, creep can be characterized by models in which the immediate elastic deformation is increased by a viscous deformation, resulting in a temporal function. For this reason, the calculation of the natural frequency of vibration and the stability verification of a slender column should include the reducing effects of stiffness both of axial force and creep. The first one can be considered through the geometrical portion and the second one by the introduction, in the conventional portion, of a variable elasticity modulus over time, obtained in relation to the adopted rheological model. A numerical simulation was performed to evaluate the aspects above, considering a bar compressed by a force at the free end equivalent to 10% of the Euler critical force, plus its own weight, adopting a rheological model with three parameters for the variation of the elasticity modulus. The results show differences of 60% and 50% for the frequency and elasticity modulus, besides defining the exact instant of column collapse in the case of its non-observance.Keywords: Three-parameter model; Vibration; Stability.A FLUÊNCIA NA FREQUÊNCIA FUNDAMENTAL E NA ESTABILIDADE DE UMA COLUNA ESBELTA DE MADEIRA DE SEÇÃO COMPOSTA RESUMO -A fluência é um fenômeno que pode ocorrer em estruturas de madeira por ser esse um material viscoelástico. A fluência pode alterar os parâmetros puramente elásticos determinados nos ensaios iniciais de caracterização da madeira, pois o seu comportamento depende da reologia do material, mesmo com um nível de tensão constante. Matematicamente, a fluência pode ser caracterizada por modelos onde a deformação elástica imediata é acrescida de uma deformação viscosa, resultando em uma função temporal. Por essa razão, o cálculo da frequência natural de vibração e a verificação da estabilidade de uma coluna esbelta devem incluir os efeitos redutores da rigidez tanto da força axial quanto da fluência. O primeiro pode ser considerado por meio da parcela geométrica e o segundo pela introdução, na parcela convencional, de um módulo de elasticidade variável com o tempo, obtido em relação ao modelo reológico adotado. Para avaliar os aspectos mencionados, foi realizada uma simulação numérica, considerando uma peça comprimida por uma força na extremidade livre equivalente a 10% da força crítica de Euler, mais o seu peso próprio, adotando-se um modelo reológico de três parâmetros para a variação do módulo de elasticidade. Os resultados indicaram diferenças de 60% e 50% para a frequência e para o módulo de elasticidade, além de definir o instante exato de colapso da coluna em caso de sua inobservância.Palavras-chave: Modelo de três parâmetros; Vibração; Estabilidade.

The building technique of light wooden framing, i.e., woodframe, represents a great innovative goal of construction, due to the very efficient levels of rationalization of material, operational flexibility and productive agility. In addition, excessive use of natural materials of renewable character in the woodframes, as the wood of planted forests, contributes to sustainability, a desired factor in most modern homes. In recent years, Latin American countries have suffered from the constant housing deficit, which destroys the possibilities of the first property by the neediest populations. Therefore, it is necessary to propagate studies, research and information on industrialized housing construction techniques, such as woodframe. This study focused on the exhibition by a state of the art of this innovative wooden housing typology, emphasizing its advantages, importance, types, and its current panorama in the regions in development stage, such as Latin American countries. Currently, the woodframe is known as a modern wooden residential technique, and it is conquering the public of all kind of economic classes, because of its innovation, lightness, competitive costs, and also by the efficient levels of sustainability, cleanness, assembly time, and rationalization of raw materials.Keywords: light framing, wooden housing, wood-frame, dissemination, strategies. RESUMENLa técnica de construcción de entramado ligero en madera, i.e., woodframe, representa un gran objetivo innovador, debido a los niveles muy eficientes de racionalización de material, flexibilidad de las operaciones, y agilidad productiva. Además, el uso excesivo de materiales naturales de carácter renovable en los entramados ligeros, como la madera de los bosques plantados, contribuye con la sostenibilidad, un factor deseado en la mayoría de las viviendas modernas. En los últimos años, los países latinoamericanos han sufrido el constante déficit de viviendas, lo que destruye las posibilidades de la primera propiedad de las poblaciones más necesitadas. Por lo tanto, es necesario propagar los estudios, la investigación y la información sobre las técnicas de construcción de viviendas industrializadas, como el entramado ligero en madera. Este estudio se centró en la exposición por un estado del arte de esta innovadora tipología de vivienda en madera, destacando sus ventajas, importancia, tipos y su panorama actual en las regiones en fase de desarrollo, como los países de América Latina. En la actualidad, lo entramado ligero en madera es conocido como una técnica de viviendas en madera moderna, y que está conquistando al público de todas las clases económicas, debido a su innovación, ligereza, costos competitivos, y también por los niveles eficientes de sostenibilidad, limpieza, tiempo de montaje y la racionalización de las materias primas.Palabras claves: entramado ligero, viviendas en madera, wood-frame, diseminación, estrategias. 78