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In the current construction market there is a high demand for sustainability. In addition to that the Brazilian government is enacting tougher and tougher legislation on the disposal of solid construction waste. These demands increasingly make the construction company responsible for the entire lifecycle of its waste as well as the accompanying cost and environmental impact of solid waste. A software program was used in the research which allows construction companies gather information about waste. This helps the decision makers, at all different levels of the company improving waste management through better decisions. The software program was used during the construction of two residential buildings, constructed by a large construction company in the South of Brazil. Five key performance indicators were used by the construction company team: Generated Waste Height (cm), cost per built area (R$ m-²), Waste Segregation Quality Index (WSQI), Effective Waste Management Index (EWMI) and Waste Management Quality Index (WMQI). After four months the total cost of waste management was R$ 83,551.71 for site A and R$ 91,668.02 for site B. About 70% of the waste was raw material waste. The software program provided information not previously available, which made it possible to calculate the cost of material loss, indicating corrective actions, all without losing sight of cost reduction opportunities for the management of Solid construction Waste (SCW).

Este estudo piloto visa desenvolver um asfalto auto cicatrizável através de aquecimento por micro-ondas, buscando reduzir tempo de processamento, economizar energia e permitir aplicações reais em um futuro próximo. Os compósitos foram produzidos com diferentes porcentagens de fibras curtas de aço obtidas da indústria da cutelaria, que foram introduzidas no asfalto com o objetivo de servir como fonte de calor, permitindo assim o aquecimento por micro-ondas. Características estruturais, morfologia e comportamento térmico das fibras curtas de aço foram obtidos por meio de difração de Raios-X, Fluorescência de Raios-X, Microscopia Eletrônica de Varredura (MEV) e Análise Térmica (TGA), que também foi utilizada para verificar a variação da massa do compósito com a temperatura. A temperatura do compósito foi monitorada durante o aquecimento para determinação da taxa de aquecimento em função da porcentagem de fibras. Ensaios foram realizados para determinar viscosidade Brookfield, penetração, ductilidade, ponto de amolecimento e densidade, permitindo assim a caracterização das propriedades físicas da amostra mais representativa do compósito. Os resultados mostram a viabilidade do aquecimento por micro-ondas para produção do compósito, indicando potencial para futuras aplicações como asfalto auto cicatrizável e reparo de pavimentos. This pilot study aims to develop a self-healing asphalt through microwave heating, to reduce processing time, save energy and allow real commercial applications in a near future. Asphalt based composites were produced with different percentages of steel short fibers, obtained from the cutlery industry, to serve as a heat source for microwave radiation. Structural characteristics, morphology, and thermic behavior of the short steel fibers were characterized through X-ray Diffraction, X-ray Fluorescence, Scanning Electron Microscopy and Thermogravimetric Analysis, that was also used to verify the relation between mass variation and temperature of the asphalt-based composite. Temperature was monitored during micro wave heating to determine the heating rate of the composites with different percentage of fibers. Brookfield viscosity, penetration, ductility, softening point and density tests were carried out to characterize physical properties of the most representative asphalt-based composite. Results show the feasibility to use microwave heating in the production of the composite, indicating potential for future application as self-healing asphalt and pavement repair.

Currently, artificial neural networks are being widely used in various fields of science and engineering. Neural networks have the ability to learn through experience and existing examples, and then generate solutions and answers to new problems, involving even the effects of non-linearity in their variables. The aim of this study is to use a feed-forward neural network with back-propagation technique, to predict the values of compressive strength and modulus of elasticity, at 28 days, of different concrete mixtures prepared and tested in the laboratory. It demonstrates the ability of the neural networks to quantify the strength and the elastic modulus of concrete specimens prepared using different mix proportions.

An experiment on the behavior of two types of circular reinforced concrete pipes under three-edge-bearing test is analyzed and discussed. Current study compares the strength of spigot-pocket (SPP) and ogee joint pipes (OJP). In the experimental analyses thirty-two pipes, nominal diameter 800 and 1200 mm, divided into two series of 16 pipes each, were tested. Each series was composed of 12 spigot-pocket pipes (SPP) and 4 ogee joint pipes (OJP). Experimental results of the loading versus displacement curves indicated that pipes behave similarly to a circular ring, since the OJP presented maximum loads 12 and 4% higher than those obtained for SPP respectively for nominal diameters 800 and 1200 mm. Pocket influenced load cracking, with 6.4 and 33% higher for SPP when compared to OJP for nominal diameters 800 and 1200 mm, respectively. Further, the presence of the pocket increased the pipe´s stiffness.

This study analyzed the mechanical behavior of shear strength of steel fiber-reinforced concrete beams. Six beams subjected to shear loading were tested until failure. Additionally, prisms were tested to evaluate fiber contribution to the concrete shear strength. Steel fibers were straight, hook-ended,35 mmlong and aspect ratio equal to 65. Volumetric fractions used were 1.0 and 2.0%. The results demonstrated a great contribution from steel fibers to shear strength of reinforced concrete beams and to reduce crack width, which can reduce the amount of stirrups in reinforced concrete structures. Beam capacity was also evaluated by empirical equations, and it was found that these equations provided a high variability, while some of them have not properly predicted the ultimate shear strength of the steel fiber-reinforced concrete beams.

This paper presented a study on the behavior of an embankment, 5.0 m high, reinforced with geogrids, and constructed over a soft soil 7.0 m thick. In order to determine the design strength (Td) of the reinforcement, it was carried out a limit equilibrium analysis using the following methods: Simplified Bishop (1955) and Corrected Janbu (1954), for the hypothesis of circular and non circular slip surfaces respectively. In order to verify the behavior of the reinforced embankment, finite element analyses were performed using the software Phase2. Therefore, this work presented the determination of the reinforcement load design, verification of the magnitude of reinforcement strains, determination of the plastification zones in the foundation soil due to the elevation of the compacted soil, and values of distortion and horizontal displacement of the soft soil and mechanism of mobilization of reinforcement load.

Sustainable development requires the existence of a production network that includes the reuse of construction waste for new materials. Current analysis investigates an optimal soil-cement composition made up of construction and demolition waste for the manufacture of pressed bricks. Soil-cement bricks were manufactured from construction and demolition wastes (CDW), A-4 classified fine sandy soil and cement CP II Z 32. Laboratory tests, comprising test compaction, optimum water content and maximum dry specific weight, consistency limits, grain size distribution and linear shrinkage, were made to characterize the materials researched. Compressive strength and absorption tests were also undertaken in different combinations of composition. Results showed that the application of CDW improved soil-cement qualities and reduced shrinkage of the material used. O desenvolvimento sustentável requer uma cadeia produtiva na qual se insere a reutilização dos resíduos de construção na composição de novos materiais. Objetivou-se neste trabalho estudar uma dosagem ótima para o solo-cimento, composto com resíduos de construção e demolição, visando à confecção de tijolos prensados. Os materiais utilizados foram resíduos de construção e demolição (RCD), solo arenoso fino de classificação A-4 e cimento CP II Z 32. Foram feitos ensaios de caracterização dos materiais em laboratório como, ensaios de compactação, umidade ótima e massa específica aparente seca máxima, determinação dos limites de consistência, análise granulométrica e retração linear. Foram também realizados ensaios de compressão simples e absorção em tijolos em diferentes composições de traços. Os resultados obtidos mostraram que a aplicação de RCD beneficiou as propriedades do solo-cimento e diminuiu a retração do material.

This paper addresses the adaptation of the method of classification of unpaved roads developed by Eaton to the field conditions of local roads from the city of Viçosa, Minas Gerais State, Brazil, considering its potential as a support tool for the management of these roads. This study was developed encompassing objective evaluation, carried out with the application of a note scale, and subjective evaluation, according to the methodology of Eaton, which were performed by a team that accomplished the field inspections, attributing notes to the 20 sample units, each one 50 meters long and representing 10 analyzed unpaved road segments. Conclusions are as follows: (i) it was not observed any correlation between data from the objective and the subjective field evaluations, leading to the conclusion that the use of the Eaton and others methodologies can be misleading to the management of the maintenance of unpaved not reflecting their real priorities; (ii) there is correlation between the subjective evaluation of the road sections and the subjective evaluation of all sample units, indicating to be consistent the application of this procedure. Este artigo apresenta a adaptação do método de classificação de estradas não-pavimentadas proposto por Eaton às condições encontradas em rodovias vicinais do município de Viçosa, Estado de Minas Gerais, considerando a sua potencialidade como ferramenta de suporte à gerência destas vias. Este estudo foi desenvolvido a partir de avaliações objetiva, realizada com o emprego de uma escala de notas, e subjetiva, em obediência à metodologia de Eaton, que foram conduzidas por uma equipe treinada previamente que executou inspeções de campo, atribuindo notas a 20 unidades amostrais, possuindo cada uma delas 50 m de comprimento e representativas de 10 trechos analisados de vias não-pavimentadas. A análise dos dados desta pesquisa possibilitou concluir que: (i) não houve correlação entre os resultados das avaliações subjetiva e objetiva, e a aplicação da metodologia de Eaton à gerência de manutenção de vias não-pavimentadas pode não refletir as suas prioridades reais; (ii) a avaliação subjetiva do trecho e a avaliação subjetiva do conjunto de suas unidades amostrais são correlatas, indicando ser coerente o emprego deste procedimento.