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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior

The generation of residues and its consequent, correlated impacts has been a concern and has mobilized the technico-scientific field in the search for solutions seeking to make productive activities sustainable. In the productive chain of civil construction the segment of tile production from red ceramics generates residues with no appropriate destination and which, in turn, produces losses to the industry, the public administration and the society. A diagnosis of these residues shows that the generated amount is significant, however there is potential for recycling it in civil construction, which should be investigated. This work reports on both the production of reference concrete with natural aggregates and concrete with partial and total replacement of the large aggregate by the recycled aggregate of ceramic tiles. The recycled aggregate presents significant differences regarding the basaltic large aggregate that was used, with much lower apparent specific mass and much higher absorption of water. The concrete thus produced was compared in the fresh state, controlling for the reduction of the cone log. It was verified that the consumption of water for production of the concrete with recycled aggregate is higher and that it is dependent on the rate of aggregate water absorption. Also, the effective water/cement relation is uncertain. The properties of the hardened state: resistance to compression, resistance to traction, and module of elasticity were also comparatively evaluated. The concrete, with recycled aggregate, presented lower mechanical resistance than the reference concrete. Maintaining the cement consumption and constant workability, the mechanical resistance was superior when using a plasticizer addictive. The same occurred when the water/cement relationship was kept constant with higher cement consumption.

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior

In the concrete might occur cracks, due to the combination of residual stresses, cure or hydration, fluency effects, retraction and temperature effect. The objetive of incorporating steel fibers to concrete is to control the micro-cracking during aplication of loads and also improve the mechanical and residual resistance to fracturing properties . The toughness of steel fiber reinforced concrete is a fundamental property to control cracking and is determinated by flexural bending test of prismatic beams. The advantages to use SFRC in the civil construction are: better cavitation resistance, improves the strength impact plus the shock thermal and increase the ductility by delaying the crack propagation in the concrete structural elements that is subjected to the tension or tension by flexural. This study, examines experimentally the mechanicals behavior of prismatic specimens of SFRC s toughness, according to the international recommendations of ASTM C1609 (2010), EN 14651 (2007) e JSCE-SF4 (1984). On next phase, the research sought to evaluate the influence of compressive strength and the fiber rate s behavior. The experimental program consisted in two matrices of 30 MPa and 40 MPa with two dosages of fibers corresponding to 60 kg/m³ and 30 kg/m³ (0,77 % and 0,38 % in volume) formed four composite of fibers. 64 prismatic specimens were cast to evaluate the tenacity and 132 cylindrical specimens to characterize the SFRC through the compression tests, modulus of elasticity and tensile by diametric compression (Brazilian test). In relation to the method of tests, the result shows that the increasing toughness of SFRC was higher when the fiber content increased the composite compared to the change in compressive strength. The EN 14651 that uses notched specimens, it is interesting method to determine the toughness of steel fiber reinforced concrete, because the method obtained lower coefficient of variation for toughness values and the crack it always propagates in the plane of the notch.

The measurements of a physical quantity invariably involve errors and uncertainties. The results of the testing of compressive strength of concrete are not exempt from this rule. Measure is an act of comparison whose degree of accuracy can depend on instruments, operators and the measurement process itself. In this work were analyzed questions that involving the intervening factors of the quality of the concrete compressive results, and, been tested the trustworthiness with which these assays have been produced by several laboratories. The focus is on the measurement errors. Your organization has involved a conceptual review of \"quality\" and its relation to the constructions in concrete; sequentially, has organized an application of tests to verify the trustworthiness of their results through two complementary ways. The first, to analyze the dispersion of results by different methods; and the main form of the reference test, established from a result set as the default method; and the other in order to characterize the types of errors produced. Their results, irrefutable regarding the methodology used for the production of his bodies of evidence and significant for the strategy used for data searching allowed to identify an undesirable state for conditions that defined the level of its reliability. Classified as inconsistent, a considerable number of laboratories evaluated in three different stages of experimental verification, presented as the results of their measurement, inadequate numbers to the strength of concrete, not meeting the expectations of desirable accuracy for this important procedure of quality control production.

This work claims to study the technical feasibility of using ferrocement panels as permanent self-supported formworks for execution of bridges on local roads. It is justified by changes in the production structure of agriculture in general that resulted in changing the type of traffic, impacting the service life of special engineering structure and also the limited capacity of infrastructure investments and technical capacity of municipalities to whom these systems are jurisdictional . The study was done by the development of theoretical models of a size which can be positioned with simple equipment and check its structural plates. The methodological approach included bibliographic and document analysis research. The theoretical development studies considered the reference group recognized research, relevant technical standards and analytical models already consolidated.

The household cleaning effluent from a manufacturing company of cleaners located in Uberlândia/MG was treated with oxidative processes O3/pH7, O3/pH3, O3/pH10, O3/pH3/Fe2+, O3/pH3/Fe3+, O3/pH3/Mn2+, O3/pH10/Activated Carbon 1 g/L and O3/pH10/ Activated Carbon 2 g/L. Also the study of the stripping of volatile organic compounds in the effluent was evaluated with the use of compressed air and pure oxygen as the carrier gas. Results were evaluated in terms of percentage removal of turbidity, COD and true color parameters, the last two being those of greatest interest. Also evaluated whether variations in the values of alkalinity and pH obtained. The spectrum scanning UV-VIS was used as an auxiliary tool of analysis. The COD removal efficiency was low for all the treatments, achieving maximum removal of 7.5%. The low removal efficiencies of organic matter may be associated with low production capacity of O3 in 1.8 gO3/h and the possibility of generation of byproducts of ozonation, not quantized in this work. The color removal reached higher values, with maximum removal achieved around 60%. The homogeneous catalytic ozonation treatment in O3/pH3/Fe3+ system was more efficient both for the decolorization of the effluent and for the oxidation of organic matter higher, possibly by improved interaction of the catalyst with the chemicals found in the analyzed matrix, since the mechanism of the ozonation process is not established tatalmente but varies considerably with the type of metal species used and their interaction with the compounds of the matrix.

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior

The rapid urban growth in many Brazilian cities in the twentieth century occurred without the proper planning and infrastructure. In these cities, floods cause great material and human losses every year. Therefore, the authorities and community must propose and implement flood control measures after detailed studies of the characteristics of the watershed . Thus, hydrological simulations of the stream Jataí watershed located in Uberlândia/MG, was performed using the software ABC - Complex Watershed Analysis, from the University of São Paulo considering the return period of 100 years for the project rain. This watershed has an area of 15.99 km² and was discretized by sub-basins considering the land use and occupation at the current urbanization and critical scenario (fully urbanized and occupied basin). The damping reservoir existent in the study area were considered in the simulations and it was proposed the implementation of a parallel damping reservoir near to the watershed output. The sub-basins 02 and 08 simulated alone at the critical scenario provided the highest maximum flow rates of 193.17 and 162.78 m³/s respectively. Furthermore, the damping reservoirs 02 and 05 showed the largest decreases of input hydrogram peak flow with maximum reductions of 86.3 and 76.6% respectively at the current urbanization scenario. The implementation of the proposed parallel damping reservoir allowed the reduction of peak flows at the basin outlet of 26.8% from 211.65 to 154.87 m³/s in the current scenario and 22.3% reduction from 262.28 to 203, 86 m³/s at the critical urbanization scenario. Based on these results, it is possible to conclude that the damping reservoirs are very important to control runoff and it is necessary and urgent to implement new flood control measures in the Jataí stream watershed to reduce the inconvenience caused by heavy intensity rains.

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior

Fundação de Amparo a Pesquisa do Estado de Minas Gerais

The safety fundamental principle of reinforced concrete structures related of a possible collapse is that the security does not depend on the concrete resistance tensile strength to eliminate the risk of collapse without notice. The cracking caused by tensile stresses can affect the concrete structure and should be avoided to the natural structural collapse doesn t occur. The diagonal crack that appears on the act of breaking is called critical crack, characteristic of shear failure. In this work were experimentally studied the additional mechanisms from the shear resistant trusses in reinforced concrete frames without transverse reinforcement. The experimental experiments consists on testing eight frames that were subjected to a simple bending. Two concrete grades of characteristic the compressive strength were considered on the construction of the frames. To resist the bending stresses, the frame s beams are designed in the field 3 of the ultimate limit states. Different rates and diameters of longitudinal reinforcement were used. In all frames weren t considered the use of transverse reinforcement in the region of shear on the beams. From the results obtained were analyzed the proposed criteria to define the portion of the contribution for the shear resistance mechanisms of concrete without the use of transverse reinforcement and the influence of the concrete resistance and longitudinal reinforcement rates in the numerical results experimentally obtained.

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior

The use of concrete walls in single-family buildings had greatly increased in recent years. To meet the demand of housing construction of social interest and the need to improve performance, business construction have sought new construction systems being one of them the walls of reinforced concrete with self compacting concrete or entrained air. The evolution of the use of concrete walls culminated in the publication, in May 2012, the NBR 16055. The purpose of this paper is to present the results of a survey on the actual performance of air incorporated into plates, considering the climatic variations of the period winter. The control variable is the heat conduction gradient, aiming the thermal performance of housing. The experimental program consisted of performing panels 16 (quantity determined by ANOVA), and reference 4 and 4 for each dose developer air additive (0.04%, 0.08% and 0.12% on the cement consumption ). The thermal test was conducted in a chamber with two thermally insulated compartments and independent control of temperature (10 oC to 25 oC) and relative humidity. The partition between the two compartments the plates were placed. They determined the physical properties in fresh and hardened specimens and the behavior of each group with respect to thermal conduction. For the percentage of additive used, the total air content ranged from 2.8% to 11.88% and the frustoconical rebate increased from 21 mm to 107 mm. The results showed that the density decreased to 11% when incorporated additive. The compressive strength had reductions of up to 53% at 28 days of age and the modulus of elasticity also reduced by 26%. In the thermal test, with a chamber ranging from 10 ° C to 25 ° C and maintained at 10 ° C another, the concrete with additive was 0.04% with a temperature of approximately 1.5 ° C lower than the reference concrete.

The aim of this work is to study the economic-financialviability to deploy and operate a paratransit network to meet demands of commuting trips for employees of a private company in Uberlândia, MG. The study was developed based on employees who leave in the Santa Mônica neighborhood, whose addresses were geocoded and inputted on a digital map. The information was inputted in the TransCAD software in order to determine clusters corresponding to bus stops considering the maximum walking distance for passengers to have access to the service. Optimization studies of routing and trip times were done, taking into account the vehicle capacity as a parameter, which allowed for the scheduling of the transportation service. Once calculated the operational parameters, the fares were calculated by using the methodology adopted by GEIPOT. In the end, it was performed an economic and financial viability of implementing and operating the paratransit service. It was compared the amounts incurred by the company in funding the Vale-Transporte Program with those indicated in the farestudies. The work concluded that the company could deploy and maintain their own network to transport its employees, with equivalent costs, if compared to Vale-Transporte Program, and higher service level, if compared to regular bus service.