This research aimed to investigate the mechanical and physical properties of Roller Compacted Concrete (RCC) used with Recycled Concrete Aggregate (RCA) as a replacement for natural coarse aggregate. The maximum dry density method was adopted to prepare RCC mixtures with 200 kg/m³ of cement content and coarse natural aggregates in the concrete mixture. Four RCC mixtures were produced from different RCA incorporation ratios (0%, 5%, 15%, and 30%). The compaction test, compressive strength, splitting tensile strength, flexural tensile strength, and modulus of elasticity, porosity, density, and water absorption tests were performed to analyze the mechanical and physical properties of the mixtures. One-way Analysis of Variance (ANOVA) was used to identify the influences of RCA on RCC’s mechanical properties. As RCA increased in mixtures, some mechanical properties were observed to decrease, such as modulus of elasticity, but the same was not observed in the splitting tensile strength. All RCCs displayed compressive strength greater than 15.0 MPa at 28 days, splitting tensile strength above 1.9 MPa, flexural tensile strength above 2.9 MPa, and modulus of elasticity above 19.0 GPa. According to Brazilian standards, the RCA added to RCC could be used for base layers.
DEDICATÓRIAAos meus pais queridos pais, Noel e Ieda, Pelo constante incentivo e grande amor dedicado. Ao meu irmão Rogerio e à minha prima Vanessa,Como estímulo à busca do conhecimento. AGRADECIMENTOSA Deus pela paz, o amor, o conhecimento e a motivação que tem me concedido no decorrer de minha vida.Aos Professores Paulo César Lima Segantine e Irineu da Silva pela valiosa orientação e contribuições concedidas durante todas as etapas de realização deste trabalho.Aos meus pais, Noel e Ieda, a quem dedico as minhas alegrias e os bons resultados do meu trabalho pelo carinho e incentivo ao longo de todas as etapas de minha vida. The mathematical model for the geometric transformation of coordinates is used to georreference information extrated from digital maps. The performance of coordinate transformation models is directly related to accuracy of control points identified in the map, since by means of the utilization of GNSS technology, it is not difficult to measure the coordinates of a point in the ground with accuracy. For this reason, it is possible to obtain a reliable georreferencing if the coordinates of the control points are accurately positioned on a map. However, as most of Brazilian municipal districts maps are old and out-of-date, it is difficult to locate a point accurately out of the geographic elements represented in the map. Depending on both the quality of the digital map and the technique used to locate the points, such coordinates may show distinct levels of reliability as a function of their accuracy. If the different accuracy of the control points is not taking into account, the performance of the coordinate transformation model can be reduced. Depending on map scale, this difference can make impracticable a study that depends on a good accuracy of the coordinates of points obtained from a georreferecend cartographic product. In order to avoid that the performance of the coordinate transformation model reduce the reliability of the georreferencing, it is important that each coordinate receives an appropriate weight according to its accuracy. In this context, the objective of this research was to develop a method, validated through a case study, that could impart reliability to georreferencing, as a function of the accuracy of the coordinates of the control points identified on a map, using a mathematical model to coordinate transformation. The key-point is to attribute a weight to each control point related to its accuracy level. The performance of this procedure was evaluated both for a high quality, standard map, and for a map with unknown quality. Different evaluations were performed and the best results were obtained using the procedure of attributing weights to the control points related its accuracy. As a contribution for the academic and technical areas, this research brought light to a question not considered until now, that is the importance of attributing weights to the coordinates of the control points as a function its accuracy in the digital map. Georreferencing becomes more relia...
This article studied the location of dry ports from the perspective of reducing impacts caused by seaport activities on the urban environment. The main objective was to construct a model based on multiple-criteria decision analysis coupled with the geographical information system for selecting areas subject to the location of dry ports. An important point was the definition of restriction and factor criteria for the preparation of this model. The distance from the seaport was defined as the most relevant criterion, followed by the road hierarchy network, population density, vegetation, and declivity, respectively. The predominant restrictive criteria were: permanent conservation areas and non-building zones. For the validation of the model presented, it was necessary to perform a case study on a city located near a seaport, and that has been legalized seaport activities in its legislation. The result showed that the areas nearest to the port, with less density of household units, and located near main roadways are the most feasible for location of dry ports. It was proven that the usage of multi-criteria analysis for selecting areas subject to the location of dry ports can be a manner for added support in the preparation of master plans for cities surrounded by seaport areas.
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