Mestrado em Engenharia Civil

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A eficiência energética do consumo de combustível em uma ferrovia heavy haul
(Universidade Federal do Espírito Santo, 2017-05-19) Cabral, Eric Wilson Santos; Cruz, Marta Monteiro da Costa; Morais Neto, Gregório Coelho de; Salles, José Leandro Félix; Fardin, Jussara Farias
In the Brazilian scenario from 2001 to 2015, the value of diesel rose 210%, which directly reflects the costs of the companies in the transportation segment. Among the challenges in the daily life of heavy haul railways is the cost reduction, which can be achieved by improving energy efficiency. It is then necessary to act effectively to seek the reduction of the ratio of liters of fuel consumed per Gross Ton kilometers multiplied by thousand (L/KTKB). This study aimed to identify which controlled variables in the railroads have a correlation with KTKB. Statistical analysis and continuous rail simulation tools were used, within scenarios defined according to the operational reality of a heavy haul railroad. The variables analyzed were the average weight per wagon, the number of stops of trains, average kilometers between stops (KMEP) and the type of train formation (TF). The possibility of saving with the change in the operational procedure of stops of the trains for changes of drivers was evaluated. In addition to the simulations, the fuel volume in the tank began to be monitored in real time, a system of shutdown and automatic locomotive activation was implemented and the operators were made aware of the reduction of fuel consumption. As a result, it was observed that the energy efficiency of the railway improved by 13% over the period 2014 to 2016, with a reduction in diesel consumption of 1.93 L/KTKB to 1.68 L/KTKB.
A influência da envoltória no consumo energético em edifícios comerciais artificialmente climatizados na cidade de Vitória-ES
(Universidade Federal do Espírito Santo, 2012-04-03) Bernabé, Ana Carolina Alves; Alvarez, Cristina Engel de; Gama, João Luiz Calmon Nogueira da; Fardin, Jussara Farias; Multfarth, Roberta Consentino Kronka
The deployment of cities have motivated the proposition of building more and more vertical in order to meet the demands for urban densification. Over time, the vertical development was linked to new technologies that initially came to give to the architect more projectual freedom. However, the possibility of reproducing models referenced in a modern and international style, led some professionals to neglect the close relation between architecture and the environment that it is inserted, leaving to artificial systems the role of ensuring thermal comfort for the users. However, the new energy scenario brought a reflection of the high demand for energy consumption in buildings, resulting in discussions, studies and development of a new reality, based on the concepts of energy efficiency. It is within this perspective that the research falls. The goal is to identify how and how much some strategies applicable to architectural envelope and inserted in the climate context of Vitória-ES, can influence the energy consumption of commercial buildings verticalized and artificially conditioned. The methodology proposed 108 models parameterized matching values for five investigated variables, they are: orientation, window wall ratio, solar factor, the existence of sun protection and absorptance of the opaque surface. These buildings were modeled after a reference building, so all other variables were controlled. As output data for the simulations we have established the final energy consumption. The analysis of these results was established in two ways. The first included the classification of the models that have achieved the level of efficiency through the procedure established by RTQ-C. The second involves the analysis of general and individual influence of each variable, and the potential for increase and reduction of energy expenditure of each one. As a result, it was found that changing the variables investigated led to a reduction of up to 27.88% in final consumption for the proposed model. The investigative tests suggest an even greater potential savings face to the most appropriate use of louvers and indicate the importance of lighting control in some cases.
A INFLUÊNCIA DOS SUBSISTEMAS DE VEDAÇÃO VERTICAL NO DESEMPENHO ENERGÉTICO DO EDIFÍCIO
(Universidade Federal do Espírito Santo, 2020-03-04) Costalonga, Filipe Galina; Alvarez, Cristina Engel de; https://orcid.org/0000000238988515; http://lattes.cnpq.br/5240388600131197; https://orcid.org/; http://lattes.cnpq.br/; Rodrigues, Edna Aparecida Nico; https://orcid.org/; http://lattes.cnpq.br/2506902397204906; Vieira, Geilma Lima; https://orcid.org/; http://lattes.cnpq.br/5783172236615493
The world is becoming increasingly urbanized. In these circumstances, reducing the consumption of energy from buildings is an extremely important aspect for the sustainable development of the new buildings that will be built to supply the accelerated urba
Aderência de revestimento de argamassa em bloco de concreto celular autoclavado
(Universidade Federal do Espírito Santo, 2012-05-14) Pagani, Angelo; Tristão, Fernando Avancini; Gama, João Luiz Calmon Nogueira da; Vieira, Geilma Lima; Araújo, Georgia Serafim
This study aims at deepening investigations on adherence of mortar coats to autoclaved aerated concrete block.Among the materials used for sealing, autoclaved aerated concrete block is the one with the lowest thermal transmittance rate and lowest density, which qualifies it to be employed and also lead to reduction in costs of building structures. We investigated characteristics of autoclaved aerated concrete blocks such as apparent dry density, compressive strength, water initial and total absorption, and substrate adherence strength. Although it is a laboratorial test, we adopted solutions that can be used in the construction site, such as water spraywashing the substrate to eliminate dust that can compromise adherence; wetting coat mortar with water 12 hours after curing begins so as to avoid early evaporation of water; and wetting substrate before applying coat mortar. Fresh state mortar consistency, water retention, exudation, mass density and air content were investigated. For hardened mortars, mass density, bending tensile strength, compressive strength, wicking and wicking coefficient were assessed. In its fixed state, substrate was assessed for water absorption through pipe method and pull-off adherence strength. Study mortar mixes had variations in each of their components (cement, lime and sand) and mixing water was constant in relation to the amount of sand, with a small variation in the consistency rate. Test results showed that pull-off adherence strength that autoclaved aerated concrete blocks can stand is higher than those set by coating adherence standards, and that washing and wetting treatments of autoclaved aerated concrete blocks improve adherence of mortars to substrates.
Agressividade ambiental em zona de atmosfera marinha: estudo da deposição de cloretos e sua concentração em concretos na Região Sudeste
(Universidade Federal do Espírito Santo, 2011-03-25) Borba Júnior, José Carlos; Meira, Gibson Rocha; Gama, João Luiz Calmon Nogueira da; Louzada, Desilvia Machado; Vieira, Geilma Lima
The concrete structures that are built close to the sea suffer the environmental aggression caused by the marine aerosol. The marine aerosol is a sea salt airbone formed by the ocean waves movement and by the friction of the wind against the surface of the ocean water. The quantity of salt found in the aerosol is bigger the more the winds of the region are and the less the distance from the coast is. That aerosol is transported by the wind towards the continent, and then it is deposited on the concrete surface structures. The chloride that is deposited enters into the concrete by an absorption and ionic diffusion, and may cause the corrosion of the framework. This work aims to measure the concentration of chlorides in the marine aerosol and associate it with the concentration of chloride in the concrete. To do that, five natural exposition point were selected to measure the sea salt airbone, being three of them used to expose the concrete to the environmental aggression. The points are located in the metropolitan region of Vitoria city at 60, 65, 120, 240 and 520 meters away from the sea, being the three farthest ones used to expose the concretes. The chloride measurements found in the marine aerosol was carried out by using the wet candle test. Climate measures were also taken to characterize the region under analyses. The analyzed concretes were modeled on concrete prism test specimens with different traces, varying the relation water/cement: 0,65, 055 e 0,45. After 6 and 20 months, samples of the concretes were taken to determine the chloride tenor. The results indicate a fragile relation between the deposition of chlorides in the atmosphere and the concentration of chlorides in the concrete for the analyzed region. The deposition of chlorides, in its turn, presented low correlation with the rate flow of the winds. Anyway, it is possible to establish a behavior of the environmental aggressiveness according to the obtained determinations.
Análise comparativa da estimativa do coeficiente de permeabilidade de solos por redes neurais artificiais e métodos estatísticos
(Universidade Federal do Espírito Santo, 2023-02-17) Moreschi, Morgana; Bicalho, Katia Vanessa; https://orcid.org/0000-0002-2157-7322; http://lattes.cnpq.br/9639299365620025; http://lattes.cnpq.br/5099811764251015; Romanel, Celso; https://orcid.org/0000-0002-8812-3456; http://lattes.cnpq.br/1721981607189967; Hisatugu, Wilian Hiroshi; https://orcid.org/0000-0001-8333-0539; http://lattes.cnpq.br/6597878238749014; Ferreira, Silvio Romero de Melo; https://orcid.org/0000-0002-5760-1494; http://lattes.cnpq.br/8035357058902261; Alves, Elcio Cassimiro; https://orcid.org/0000000169712645; http://lattes.cnpq.br/6509450210637509
This research analyzes and compares the performance of artificial neural networks (ANN), statistical methods and empirical and semi-empirical correlations in predicting values of the permeability coefficient of saturated soils (ksat), from index properties that characterize the particle size distribution and the fine fraction. 8258 experimental data of ksat of soils composed of coarse and fine grains (2.50x10-13  ksat (m/s)  4.50x10-2 ), published in 08 databases in the literature, were compiled and compared, in order to assist in the understanding of the hydraulic properties of saturated soils and in the description of ksat prediction problems. Subsequently, a set of samples was selected and analyzed with a combination of different input variables for predicting log(ksat), using multiple linear and polynomial regression and ANN. The input variables considered were percentage of fines (silt and clay) (%Fines), liquid limit (LL), effective diameter (d10), uniformity coefficient (Cu) and void ratio (e). The results were evaluated based on the values of the coefficient of determination, the root mean square error and the mean absolute error. The performance of the ANNs surpassed the regressions and correlations in the literature. Of all the results of the analyses performed, ANN302, which considered %Fines, LL, Cu and d10 as independent variables, presented, numerically, the best results. The addition of a third hidden layer reduced the accuracy of the networks. The regressions and ANNs were better than the empirical correlations for the prediction of ksat, for the investigated database, and showed that the choice of variables that characterize the particle size distribution and the fine fraction was satisfactory for the experimental database. Considering that ksat is a highly variable property and a function of several interdependent properties, the ANN technique proved to be viable, mainly because it does not require prior knowledge of the mathematical relationship between the variables and because of its ability to describe problems of greater complexity. The importance of including information on the particle size and nature of the fines in ksat databases is highlighted, mainly for characterizing the permeability of samples with hydraulic properties dominated by the fine fraction.
ANÁLISE COMPARATIVA DA ESTIMATIVA DO INDICE DE COMPRESSÃO DE ARGILAS POR REDES NEURAIS ARTIFICIAIS E CORRELAÇÕES EMPÍRICAS
(Universidade Federal do Espírito Santo, 2019-11-01) Oliveira Filho, Amandio Gonçalves de; Bicalho, Katia Vanessa; https://orcid.org/; http://lattes.cnpq.br/9639299365620025; https://orcid.org/0000-0003-0605-5830; http://lattes.cnpq.br/6546712936487518; Romanel, Celso; https://orcid.org/; http://lattes.cnpq.br/; Hisatugu, Wilian Hiroshi; https://orcid.org/; http://lattes.cnpq.br/; Frasson, Antonio Manoel Ferreira; https://orcid.org/; http://lattes.cnpq.br/; Alves, Elcio Cassimiro; https://orcid.org/0000000169712645; http://lattes.cnpq.br/6509450210637509
The compression index (CC) and the compression ratio (CR) are used to calculate consolidation settlement of foundations on soft soils when requested by external loads. Several empirical correlations have been published in the literature to predict CC and
ANÁLISE COMPARATIVA ENTRE INDICADORES DE SUSTENTABILIDADE E O MARCO LEGAL DA HABITAÇÃO SOCIAL NO BRASIL
(Universidade Federal do Espírito Santo, 2020-04-03) Roccon, Carolina Simoes; Alvarez, Cristina Engel de; https://orcid.org/0000000238988515; http://lattes.cnpq.br/5240388600131197; https://orcid.org/; http://lattes.cnpq.br/; Vieira, Geilma Lima; https://orcid.org/; http://lattes.cnpq.br/5783172236615493; Lopes, Luis Manuel Bragança de Miranda e; https://orcid.org/; http://lattes.cnpq.br/
Increasing urbanization highlights the challenges for sustainable urban development. In Brazil, 86% of the population lives in urban areas, WHERE most of the country's housing deficit is concentrated. Throughout the years, several strategies have been dev
Análise da Adição de Escória de Ferroníquel de Forno Elétrico Rotativo Para Composição de Cimentos Portland
(Universidade Federal do Espírito Santo, 2024-01-29) Berghe, Rafael Vancini Schimith; Pilar, Ronaldo; https://orcid.org/0000-0002-1906-2071; http://lattes.cnpq.br/6669573444640365; Schankoski, Rudiele Aparecida; https://orcid.org/0000-0003-1306-3986; http://lattes.cnpq.br/3391191554375710; https://orcid.org/0009-0008-1206-3830; http://lattes.cnpq.br/6666407104898779; Gava, Giovanna Patrícia; https://orcid.org/0000-0003-0367-6738; http://lattes.cnpq.br/1404389625413969; Sakata, Rafael Dors; https://orcid.org/0000-0002-7022-3846; http://lattes.cnpq.br/3547547454752538
Among the viable strategies for reducing CO2 emissions by the cement industry is a reduction in the amount of clinker in cement, through the partial replacement of supplementary cementitious materials (SCMs). However, the potential decline in supplies of the most widely used SCMs has been driven by interest in research into other materials. In this context, we present ferronickel slag (FNS), obtained in the production of ferronickel alloys in a rotary electric furnace, which currently has no commercial value, being stored in yards or discarded in landfills. Therefore, the present work sought to analyze the prediction of the addition of FNS in the production of composite Portland cements, following the prescriptions of ABNT NBR 16697 (2018) "Portland Cement - Requirements". The cements were produced at 10%, 20% and 30% mass replacement of clinker by FNS, and were compared to the requirements of the Brazilian standard and to a cement with the addition of 20% limestone filler (FC-20). The materials used in the manufacture of cements were molded and characterized using SEM, x-ray fluorescence, Blaine, laser granulometry, specific mass. Furthermore, we converted the R3 assay to evaluate the reactivity of FNS and limestone. The gypsum content in the cements was defined using the isothermal conduction calorimetry test. The cement tests were carried out in accordance with the prescriptions of ABNT NBR 16697 (2018). According to the results, FNS proved to be viable as a mineral addition, presenting all standard requirements for composite cements (CP II) in the three replacement levels. The cements FNS-10 and FNS-20 were classified as class 40 and the cement FNS-30 as class 30. In the specification resistance tests, a gain in resistance was combined with 91 days of the cements composed with FNS, indicating a greater hydraulic activity in advanced ages. The incorporation of 20% of FNS was considered the optimal content for incorporation into the cement in this research.
Análise da capacidade operacional de um terminal portuário de importação de fertilizantes por meio da simulação
(Universidade Federal do Espírito Santo, 2011-09-15) Silva, André Luís Ludolfo da; Rosa, Rodrigo de Alvarenga; Bertolde, Adelmo Inácio; Frazzon, Enzo Morosini
This dissertation presents an operational capacity analysis of a port terminal fertilizer, considering the current infrastructure, the operational characteristics and future scenarios, aiming to support a better use of resources of the terminal. The proposed method consisted of the operational characterization of port terminal, identification of relevant variables for the model development, data collection and analysis. Was used the Rockwell Arena simulation software for the construction of the simulation model representing the port operation, and the model was validated for the current conditions. Based on the operational model, six alternative scenarios were generated, with changes in the rate of arrival of ships, cars and trucks, causing changes in volumes of incoming and outgoing cargo. By analyzing the results it was concluded that changes in the increased movements of ships, cars and trucks and increased storage capacity proposed in some scenarios are viable, and in other scenarios the increase in demand puts at risk the level of service the entire port system, due to the generation of queues and excessive waiting time in queue, beyond the limited capacity of some resources.
Análise da ecoeficiência de um sistema de transporte público urbano de passageiros
(Universidade Federal do Espírito Santo, 2015-08-24) Bermond, Vinicius; Rosa, Rodrigo de Alvarenga; Chaves, Gisele de Lorena Diniz; Gama, João Luiz Calmon Nogueira da
The Brazilian`s public transportation system transports over 336 million people per month in nine main cities within the country. For this reason, it is important to analyze the environmental impact of diesel and alternative fuels use to achieve environmental standards, always looking for life quality improvement. This paper proposes a methodology based on the World Business Council of Sustainable Development (WBCSD) (2000) to evaluate public transportation eco-efficiency by key performance indicators that measure the product value (V) and environmental influence (E) by the equation: ECO = V/E. These indicators can be adjusted to calculate the total energy consumption, the total emission of carbon dioxide, the total emission of each greenhouse gas, the total cost of the fuels, among others. The methodology was applied to the Metropolitan Region of Vitória (MRV) that has an integrated public transportation system called Transcol. This system transported over 190 million people in 2014 through more than 120 million kilometers travelled and serves six largest cities in the state of Espírito Santo: Vitória, Vila Velha, Serra, Cariacica, Viana and Guarapari. Transcol has a bus fleet of 1,724 vehicles, 15 different types of buses with a mean capacity of 37 seats. Different scenarios were developed representing different fuel sources from diesel oil to greener ones, such as biodiesel and electric source and different engine technologies for the buses. These scenarios were tested, analyzed and evaluated by nine indicators: emissions of Carbon dioxide (CO2), Carbon monoxide (CO), Nitrous oxide (NOx), Particulate Matter (PM), Hydrocarbons (NMHC), fuel consumption (COC), operating cost (COP), fuel cost (CCO) and cost of fleet renewal (CRF). The methodology showed that the bus fleet can obtain significant savings and lower emissions of CO2, NOx the use of biodiesel provides a reduction of greenhouse gases and sulfur emissions, although it can be more expensive and lacks adequate distribution structure. However, the use of biodiesel instead of diesel is better because it pollutes less, even though the consumption is bigger than in others fuels.
Análise da eficiência das ferrovias especializadas em transporte de minério de ferro e pelotas pertencentes às empresas mineradoras e usinas de pelotização por meio do método Data Envelopment Analysis (DEA)
(Universidade Federal do Espírito Santo, 2018-12-10) Fontan, Renata Guimarães de Oliveira; Rosa, Rodrigo de Alvarenga; Lacruz, Adonai José; Alves, Élcio Cassimiro
The worldwide market for iron ore extracts and trades more than two billion tons per year. The few mining companies set a production system integrating mines and/or pelletizing plant, railway and port to reduce their costs. These railways are considered as a cost for the mining process and cover high investments and operating costs. The study proposes to analyze comparatively the performance of twelve railways specialized in the transport of iron ore and pellets, which are properties of the mining/pellets companies. These railways are in four continents, distributed in ten countries. For this purpose, the Data Envelopment Analysis (DEA) methodology was used with Constant Scale Returns (CCR) and output orientation. The objective is to measure the efficiency of the railways and identify their position in relation to the other railways. As input variables were adopted: the number of operational wagons, the number of wagons of the most predominant train type and the load per axle of the wagon. The TKU was used as the output variable, which represents the useful ton carried by the distance traveled. Frontier Analyst software was used to solve the proposed DEA model. In the result obtained, three railroads were considered as efficient: Carajás Railroad (EFC), Mount Newman (NEWM) and Fortescue (FMG). Railroads Vitoria-Minas Railroad (EFVM), Hamersley (RTHA) and Roy Hill (RHILL) could reach their efficiency frontier with increased TKU output, as suggested by the results generated by the software. The railroads Robe River (RTRR), QNS & L, Cartier (CART), Yekepa-Buchanan Line (AML), Iron Ore Line (IOL) and Mauritania (MAUR) need to increase the TKU achieved in 2016 by more than 140% to achieve efficiency. To increase the amount of MFe and PLMFe transported, it is necessary to analyze the productive capacity of MFe mines, evaluating the production scenario: exhaustion, stability or growth. In addition, it is necessary to study the market before increasing production, since an oversupply of MFe and PLMFe could unbalance the market, reducing the price of these commodities and the profit margin of the miners and pelletizing plants.
Análise da eficiência relativa de portos multipropósito
(Universidade Federal do Espírito Santo, 2015-07-03) Martins, Karen Vassoler; Cruz, Marta Monteiro da Costa; Cardoso, Patricia Alcantara; Meza, Lidia Angulo
Port efficiency is a key factor for the sustainability of international trade and economic growth of countries. Therefore, it is essential to know the performance and conduct the proper planning of port sector. In studies of efficiency in port facilities, Data Envelopment Analysis (DEA) has been shown to be appropriate and their use has been increasing in the last 20 years. However, much of this research compares only specialized port facilities, which handle cargoes of the same nature. In order to promote efficiency analysis between multipurpose ports using DEA, this research examined a group of 29 Brazilian maritime public ports in cargo handling in 2013 towards their available infrastructure. There were used as model inputs the maximum draft in the access channel and the extension of dockage and as output variable the total cargo handled. Considering that in the handling of dry bulk, liquid bulk, general cargo and containers resources are used in different ways, it was proposed a procedure in order to avoid distortions in the technical application. The research also made it possible to identify port efficiency by cargo nature and to establish the ranking of port performance of the facilities. The results contribute to the evolution of the use of the technique and expansion of study opportunities in the port sector.
Análise da emissão de CO2 de sistemas de piso misto composto por vigas celulares via algoritmos metaheurísticos
(Universidade Federal do Espírito Santo, 2023-08-23) Silva, Gabrieli Fontes; Alves, Elcio Cassimiro; https://orcid.org/0000000169712645; http://lattes.cnpq.br/6509450210637509; https://orcid.org/0009-0001-1758-0238; http://lattes.cnpq.br/7583532122245733; Junges, Elisabeth; https://orcid.org/0000-0002-9094-2645; http://lattes.cnpq.br/4385254860391051; Silva, Amilton Rodrigues da; https://orcid.org/0000-0001-7122-2688; http://lattes.cnpq.br/1804042130645206
The increase in greenhouse gas emissions in the construction sector has led to the search for economically and environmentally more viable solutions. In recent years, there has been a growing adoption of mixed floor systems with full-depth beams. However, cellular beam floor systems have been relatively unexplored despite their advantages over full-depth beams. These advantages include the ability to span larger distances with reduced structural mass and, consequently, reduced CO2 emissions. The aim of this study is to present the optimization problem formulation for a mixed steel and concrete floor system composed of cellular beams, a steel deck slab, and steel columns. In addition to constraints related to ultimate and serviceability limit states, construction constraints related to cutting and welding were considered in the optimization problem. The solution was obtained through Genetic Algorithm and Particle Swarm Optimization. The design variables included not only beam sizing parameters but also the choice of the steel deck slab, the compressive strength of the concrete in the slab, the number of secondary beams in the floor, and the steel profile of the columns. An analysis of CO2 emissions was conducted for the optimal solutions found for the mixed floor system with cellular beams, comparing them to the mixed floor system with full-depth beams. The results indicated a reduction in emissions of over 30% when using the cellular beam system. Furthermore, it was found that constraints related to the cutting and welding process of cellular profiles did not have a significant contribution to the final floor emissions. This points to the environmental feasibility of using this type of beam.
Análise da estabilidade de edifícios altos com lajes lisas, nervuradas e nervuradas com vigas-faixa levando em consideração a interação solo-estrutura
(Universidade Federal do Espírito Santo, 2016-08-15) Passos, Vinicius de Melo; Alves, Élcio Cassimiro; Luchi, Lorenzo Augusto Ruschi e; Silva, Amilton Rodrigues da
Reinforced concrete buildings in the past were built with robust elements, providing great rigidity to structure regarding the stability of the same. With technological advances in construction over the years, arose construction systems that provided taller and slender buildings. Given that the global stability of tall and slender buildings is critical, we sought in this dissertation study some of the factors that influences the global stability of buildings of reinforced concrete, such as the type of construction system slab (flat slab, waffle slab and waffle slab with band beams), thickness of the slabs, the thickness of the hard core, coefficients that simulate the physical non-linearity of structural elements, floor height and the effect of soil-structure interaction. It was found that the above factors have influence on the global stability of buildings of reinforced concrete. Among these factors, we highlighted the coefficients that simulate the physical non-linearity of the structural elements and soil structure interaction, so that had a greater influence on global stability. For modeling and analysis of the results will be used the commercial software CAD / TQS version 17.13.
Análise da estabilidade de indicadores de desempenho em modelo de simulação de uma cadeia de suprimentos utilizando aplicativo otimizador
(Universidade Federal do Espírito Santo, 2016-08-31) Nascimento, Rodrigo Meirelles; Cruz, Marta Monteiro da Costa; Cardoso, Patrícia Alcântara; Garcia, Anilton Salles
Faced with the effects of seasonality on global market of metallic minerals, associated with its relevant logistics and production costs besides of variation of raw materials purchase prices for the steel industry, mining companies need to apply decision making, often in opposite direction of the growth. Arise as solutions of these difficulties some divestments, cost cutting, prioritizing activities and maximizing the use of its assets that can be implemented with changes in facilities and processes. In this research, was applied an optimization approach in a supply chain simulation model to get the best answers to support operating and strategic decisions making. Specifically, were investigated the inventory work levels along the chain from which is obtained, after changes in resources and processes, a maximum coal input consumption per year for the production of iron ore pellets by pelletizing plants of a mining company. A simulation model of a real mining company, developed and validated in Arena® software from another previous study, was adopted as a case study of this research and captures the complex nature of the system and an optimizer created in the add-in OptQuest® for Arena® performs the search for best solutions. The simulator is also used to generate performance results of the chain in optimized situations. Experimentation suggests that changes of capacity, changes im storage practices and variations in the capacities of processes impact in some cases and to a greater or lesser extent, input consumption. It also demonstrates the sensitivity of performance results in the supply chain when changes were applied. Performance indicators show the evolution between the results of tested cases.
Análise da incorporação do resíduo do beneficiamento de rochas ornamentais tratado termicamente na composição do cimento Portland
(Universidade Federal do Espírito Santo, 2018-05-29) Rodrigues, Larissa Helena Carnielli Howat; Vieira, Geilma Lima; Silva, Maristela Gomes da; Araújo, Georgia Serafim
In Brazil, especially in the state of Espirito Santo, ornamental rock mining reaches one of the main economic activities, generating tons of waste from this beneficiation process. The objective of this work was to evaluate the potential of the thermally treated ornamental rock residue as a partial replacement material in the Portland cement production. For the analysis of the properties of Portland cement produced in this work called CP II R, the tests of fineness, specific surface, expandability, setting time, mechanical strength and chemical analyzes were carried out by the Brazilian Association of Technical Standards - ABNT, and complementary mineralogical and microstructural tests. The residual substitution contents were 6%, 10% and 14% by mass of clinker, using as reference the mixtures of 0% and CP II Z-32 marketed. The CP II R in all contents of the residue presented values that met the criterion of the standard making possible the use of RBROTT in the composite Portland Cement composition. Physically it presented fine particles with chemical composition rich in silica and alumina. The mechanical results indicated a resistance greater than 65MPa at 120 days and the complementary analyzes demonstrated cohesive matrices with the observance of all elements of the phases of hydration. The CP II R-14% was the optimum content found in this research.
Análise da influência do diafragma externo na ligação entre viga de seção I e pilar tubular de seção circular
(Universidade Federal do Espírito Santo, 2018-08-09) Orrico, Ana Carolina Scampini Rangel; Azevedo, Macksuel Soares de; Ferreira, Walnório Graça; Munaiar Neto, Jorge
The use of external diaphragms in connections between I-beams and circular hollow section columns aims to improve efficiency of the transmission of forces and moments between these two elements. The study of diaphragms began in Japan in the 1970s, where theoretical work and experimental analysis of its application were made. In Brazil research dates to 2005, when Carvalho (2005) performed the first numerical analyzes of a connection both with and without the diaphragm. The Brazilian standard ANBT NBR 16239:2013 does not address the design of this type of connection, which is contemplated only by Kurobane (2004) in the Comité Internacional pour Le Développement et l’Etude de La Construction Tubulaire (CIDECT). The objective of this study is to analyze the behavior of external diaphragms in the connections between I-beams and circular hollow section columns. Numerical analysis was performed exploring a range of geometries for the external diaphragm and evaluating the effectiveness of the connection when both the beam and the column are loaded. The diaphragm proved to be an effective mechanism to increase the initial stiffness and the ultimate strength of the connection providing resistance gains ranging from 30 to 173%, depending on the geometry of the parts. When the column is submitted to axial loading, the model without diaphragm the value of the ultimate bending moment resistance presents a gradual reduction between 3.2% (for the smallest diaphragm) and 17%.
Análise da inicialização da cadeia de suprimento de um complexo de beneficiamento de minério de ferro utilizando simulação de eventos discretos
(Universidade Federal do Espírito Santo, 2019-12-27) Oliveira, Gustavo Bonella de; Cruz, Marta Monteiro da Costa; https://orcid.org/0000-0002-9602-1492; http://lattes.cnpq.br/3756874579954087; https://orcid.org/0000-0001-7166-6211; http://lattes.cnpq.br/1469345346532904; Cardoso, Patricia Alcantara; https://orcid.org/0000-0002-7419-0156; http://lattes.cnpq.br/6476384962630880; Salles, Jose Leandro Felix; https://orcid.org/0000000234176544; http://lattes.cnpq.br/1368496315730875
Building a self-sufficient logistics system in a company can determine its success by leveraging profits to a national and even international level of recognition. Reactivating, or even activating, an industrial plant requires a lot of planning, study and market analysis. In view of this, the use of various tools can be used from works, previous studies of gender industries, bechmarking and simulation tools, provided they are used in the right way. This paper aims to study the reactivation of an industrial plant, focusing on its logistics chain, and how long it will take for the company to return to the steady state supply of its key inputs. As a case study, the Brazilian mining company Samarco and the Fundão dam rupture, located in Minas Gerais, which took place in November 2015, were used. mining supply chain scenarios. A mining supply chain simulator was developed with actual company data prior to shutdown. The software was Arena®, with the objective of determining the time required to return the mining supply chain activities to its stable level of activity. In this sense, this study was based on the simulators warm-up period, normally disregarded in many studies and that can bring valuable information to the company. In all, 13 alternative scenarios and one real-time scenario of the system were proposed before the production interruption, and in all simulation scenarios the proposals were based on inventory levels, collaborative chain and operational production levels. As a result of the research, it was found that the greatest negative influence on the company's inventory level is the input of higher supply lead time, this input that could burden production and lead to plant disruption time. With the proposed models and interventions, it was possible to foresee solutions and study the best of them to apply to the real scenario. As a conclusion of this dissertation it can be seen that a collaborative supply between distinct supply chains can increase the efficiency of the productive return of this industry. The best scenario simulated was the mining company's partial operation with the supply through its shareholder.
Análise da interação solo-atmosfera em solos argilosos compactados não saturados: relação entre evaporação e sucção (ou umidade volumétrica)
(Universidade Federal do Espírito Santo, 2023-09-06) Poleto, Thiago Luiz; Bicalho, Katia Vanessa; http://lattes.cnpq.br/9639299365620025; http://lattes.cnpq.br/2670879835444801; Zuquette, Lazaro Valentim; Dantas, Bruno Teixeira; http://lattes.cnpq.br/9702567694302789; Alves, Elcio Cassimiro; https://orcid.org/0000000169712645; http://lattes.cnpq.br/6509450210637509
In this work, the influence of soil-atmosphere interaction is evaluated in a monitored experimental landfill divided into two symmetrical sections built with compacted clay soils treated with lime exposed to the same atmospheric conditions in Hericourt, Haute Saône region, France. For illustrating the influence of such interaction, data from monitoring soil moisture and suction and climatic conditions are presented and discussed. Potential Evaporation (Ep) values were calculated considering empirical formulations selected from the literature, commonly used and based on measurements of air temperature and relative humidity at the location. The analyzes carried out use climate data collected at a meteorological station built at the site of the landfill being monitored under study. The main objective of the work is to compare the potential evaporations (Ep) calculated by the selected empirical methods with the suction and volumetric humidity data measured in unsaturated compacted clayey soils on the surface of the landfill constructed in the study region. The measured variations of (θw) and (s) on the compacted surfaces of the two lime-treated soils (a high-plasticity clay and a low-plasticity clay) show consistency with local seasonal climatic variations. During the water deficit from May to June 2011, the measured suction values (s) increased consistently and the corresponding θw decreased, suggesting a relatively significant water evaporation effect. In the s x Ep relationship, from April to June 2011 for the empirical methods Ep based on air temperature exhibited a more substantial increase in evaporation with increasing soil suction. The empirical method based on air temperature and relative humidity did not adequately describe the water balance during the drying period. It is noteworthy that to apply the empirical methods for calculating Ep selected in these works to any location, a study with a larger database measured from different regions over several years is necessary.

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