Engenharia Civil

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http://repositorio.ufes.br/handle/10/17613

Programa de Pós-Graduação em Engenharia Civil

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URL do programa: http://www.civil.ufes.br/pos-graduacao/PPGEC

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Agora exibindo 1 - 20 de 167

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.
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.
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 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 de demanda por transportes de passageiros via modelos de regressão georeferenciados
(Universidade Federal do Espírito Santo, 2012-06-29) Ribeiro, Valéria da Cruz; Morais Neto, Gregório Coelho de; Bertolde, Adelmo Inácio; Cruz, Marta Monteiro da Costa; Shirakawa, Márcia Aiko
This dissertation - Analysis of Demand for Passenger Transport via Regression Models georeferenced - presents, and a methodology for the construction of spatial regression models and geographically weighted, a risk assessment when compared to traditional regression models and regression models with dummies variables in order to forecast demand for travel to the city of Vitoria, capital of Espirito Santo, in order to obtain information that can subsidize the transportation planning more effectively. For this, we used data from the household survey of origin and destination (OD) held in 1998 in the metropolitan region of Vitoria, four models were calibrated regression modeling of travel demand: Traditional Model Regression, Regression Model dummy Regression Model Space and Geographically Weighted Regression Model. After calibration, the models were tested from the application data in the household survey of origin and destination conducted in 2007 in the same city, to compare and validate the estimate. We conclude that the main hypothesis, or part thereof, considered in this work was confirmed that a regression model spatial or geographically weighted distances can be more explanatory than conventional regression models, since the calibration of travel demand models by weighted regression model showed values of statistical adjustments smaller than the other models.
Análise de indicadores para execução de inspeção predial regular obrigatória e diretrizes para o corpo técnico
(Universidade Federal do Espírito Santo, 2018-03-21) Vervloet, Suzanne; Vieira, Geilma Lima; Teles, Claudia Rodrigues; Conde, Karla Moreira
The building inspection is an indispensable tool for the technical monitoring of the conservation state, use and maintenance of buildings. Since 2001, several brazilian cities turned into mandatory, the regular building inspection, alerted by the occurence of acidentes which causes were related to the lackness of conservation of buildings. To supply the guidelines to the inspector professionals, the legislation in general recomend the attendance to the technical standards in force. The Norma de Inspeção Predial Nacional (IBAPE, 2012) represents an advance regarding the technical recomendations of the specific activity of building inspection, since the national regulator agency – ABNT – doesn’t have a published standard about this subject. However, some of the guidelines of the Norma de Inspeção do IBAPE require refinement and standardization in order to minimize the variability of results of the inspection reports. In this context, the aim of this research is to identify the deficiencies of legislation and normatization in force regarding to the execution and register of regular building inspection by the technical body and propose resolutive guidelines. A wide bibliographic revision, in varied and disperse sources of information, supports itself in a consistent methodology of collect, storage and evaluation of data. The creation of a database with numeric classification and dynamic feeding enables this organization. Due to the particularities of Municipal Law, the City of Vitória, ES is selected as case study. Conclusively, five results are presented: (1) Verification list for the structural system, as example of the detailing level suggested in the survey directions; (2) The GUT-SC method of anomalies and failures priorization, with well defined criteria of risk analysis, besides cost range as auxiliary tool; (3) The metodology of execution of building inspection, since hiring to delivery of the Building Inspection Report (LIP); (4) Model for the Building Inspection Report; (5) Orientative guide of costs related to the elaboration of LIP. The guidelines presented in the results compose a complete and detailed metodology of execution and register of building inspection. Once unified its application, they allow the standardization of the activity and its costs, with consequent homogenization of Building Inspection Reports, in benefit of the professionals, managers of buildings and supervisory organ.
Análise de um modelo matemático de localização na reorganização de uma rede logística estabelecida
(Universidade Federal do Espírito Santo, 2011-07-05) D'Andréa, Rafael; Cardoso, Patrícia Alcântara; Cruz, Marta Monteiro da Costa; Pizzolato, Nélio Domingues; Dubke, Alessandra Fraga
The increasing competition among the supply chains generated by economic globalization and technological innovation has required logistics networks becoming increasingly complex. Thus, planning of logistics networks has become increasingly important and the location of facilities a strategic issue in search of competitive advantage. This study is included in a stream of research about the facilities location theory and aims to analyze a logistics network established by setting the amount and location of one or more distribution centers to minimize the total costs associated with the chain as a whole, without compromising the level of service. To this end, a nonlinear programming model is proposed in order to solve a real problem of a company in the oil sector. It also proposed a method of analysis for facility location problems, which lists the main steps to be followed. Finally, it presents a sensitivity analysis in order to obtain managerial insights, where various scenarios will be generated and optimized. The results obtained by computer simulation using the AIMMS software were adequate to solve the proposed problem, with the conclusions reached in agreement with the literature.
Análise de variáveis direcionadoras de melhores práticas em operações logísticas
(Universidade Federal do Espírito Santo, 2015-08-14) Silveira, Marcos Antonio Nunes da; Cardoso, Patrícia Alcântara; Cruz, Marta Monteiro da Costa; Carneiro, Teresa Cristina Janes; Pascucci, Lucilaine Maria; Meza, Lídia Ângulo
The search for the identification of best practices is an ongoing challenge for developed any productive activity, whether focused on production of tangible or intangible assets, in this case services. Involved in this context is the logistics operations, including order processing, inventory management, shipping, transportation, and control the flow of information and resources applied. This research aims to identify with the companies analyzed whether the concepts set out in the reference models feature practical significance that is present relationship with the reality of logistics operators and are factors that can influence their results from the point of strategic and operational. Check predominant characteristics that are common in logistics operators classified as benchmarks. They evaluated the logistics operators who work in the domestic market taking into account aspects relating to best practices and variables that are direcionadoras these practices. The theoretical framework deals with the characterization of companies providing logistics services and criteria for the selection of logistics operators. The identification of performance measurement systems was discussed, as well as assessment indicators and benchmarking concepts in logistics operations and reference models. It was used based on the information disclosed in Tecnologística magazine # 223 of June 2014, which presents data for logistics providers operating in Brazil. After assessing the theoretical constructs and data interpretation was applied to envelopment analysis of technical data, using standardization, comparative evaluation and analysis of weights assigned by the model, to identify companies (logistics operators) that muster enough information to be considered as a benchmark. The ranking of efficiency presented by the DEA model was evaluated and the following variables were identified as drivers of best practice: number of current contracts, number of employees, time to market and area available for storage, being identified as INPUTs of the process. The volume of handled goods and net income were identified as OUTPUTs. These variables have been organized in a ratio of OUTPUT and INPUTs, which allowed the satisfactory assessment of the evaluated companies.
Análise dinâmica de estruturas de aço suportes de máquinas rotativas
(Universidade Federal do Espírito Santo, 2014-11-07) Ferro, Rafael Marin; Ferreira, Walnório Graça; Calezani, Adenilcia Fernanda Grobério; Oliveira, Romilde Almeida de
Adequate dynamic analysis is needed to check for Support Frame Structures of mechanical equipment to ensure not only the human user comfort as well as good conditions for the operation of equipment structure. Recent studies of Structural Dynamics and Dynamics of equipment see the difficulty in performing real models of Support Frame Structures of Rotating Machinery. Booth areas have in common study Analysis of Vibrations produced by Dynamic Loads is necessary a study comparing the two areas, which are considered the dynamic loads caused by rotating machinery in checking Support Frame Structures.. This thesis is based on a survey of the real operating conditions of Rotating Machines such as pumps, compressors and fans, targeting the correct application of Dynamic Loads produced by the equipment applied in Support Frame Structures. With the data of speed, acceleration, frequency and consequently vibration, the set will be generated Computational models of Support Frame Structures. Models of Structures with loads of equipment applied, carried out with the aid of software strap. Will be generated, in Dynamic Module, models of Support Frame Structures with connections rigid, pinned or semi-rigid. Varying loads of a model of Rotating Machinery, this study will use a centrifugal pump we can see which have the best Support Frame and Performance with enhanced reliability in relation structure versus vibration. For the purpose of design models, we use Support Frame Structures of rotating machines used in real Industries models.
Análise dinâmica de pisos mistos em aço-concreto submetidos a atividades humanas rítmicas
(Universidade Federal do Espírito Santo, 2007-05-23) Loose, Juliane Klug; Silva, José Guilherme Santos da; Ferreira, Walnório Graça; Sá, Pedro Augusto Cezar Oliveira de; Faísca, Renata Gonçalves
The application of dynamic analysis in structures is growing together with the new technologies of construction. Knowledge about the behavior of materials and its consequent optimized usage allow making structures more and more slender. This tendency of design are leading to structures systems with natural frequencies much and much lower and, therefore closer to the frequency of the dynamic excitation associated to the human beings activities, such as: walking, running and jumping. As a consequence, dynamic loads due to human rhythmic activities can be enough to cause frequencies near the resonance, making the system sufficiently vulnerable to the effects of vibrations, exceeding the recommended limits for human comfort, resulting in discomfort for people. This work intends to study the behavior of composite floor systems (steel-concrete), subjected to human rhythmic activities like aerobic activities and free jumps. For such, analysis in composite floor models will be done using the Finite Element Method (FEM). It was considered the usual techniques of discretization using the computer program Ansys. The beams are simulated by finite elements considering flexion and torsion effects. The concrete floors are simulated by elements with membrane capability. The dynamics loads were modeling using diferents metodologies. One of these, uses experimental parameters that considere effects produced by crowds, and other, use parameters from international recomendations. Later, the results obtained, in terms of the maximums accelerations (peaks accelerations), are confronted and compared to those supplied by the technical literature available about the subject, from the point of view of human comfort. The results obtained in this study show that composite floors analyzed are submitted to high accelerations that can be cause problems, because exceed the limits associated to the human comfort.
Análise do adensamento urbano no comportamento microclimático em Vitória (ES): aplicações no modelo ENVI-met
(Universidade Federal do Espírito Santo, 2018-10-09) Leal, Laiz Reis; Alvarez, Cristina Engel de; Vieira, Geilma Lima; Assis, Eleonora Sad de
The pursuit for urban environment adaptation to climate change is indicated one of the greatest challenges of this century, and the cities appear both as potential originators of the climate change as well as targets of such consequences. Therefore, the processes of urban planning are essentials, aiming to mitigate the climate change and the adaptations of cities for future events. Thus, predictive studies are required to support the decision-making, observing those highlighted and referred to computational simulations. Predictions alert that extreme events will occur in more frequency and intensity, and among them are included heat waves, in which high temperatures interfere negatively in the quality of life, and even more, increasing risks to the human health. The urban configurations that act already to modify the original environmental conditions, related to the influences of the climate changes, can have effects potentialized, interfering directly in the energy balance of the urban environment. The aim of this study is to evaluate the implications of urban density in the thermal behavior at the pedestrian level toward to the potential global warming scenario in Vitória (ES). The methodology is composed by field survey, microclimatic measurements, modeling and simulations of the measured scenarios using the program ENVI_MET 4.3, considering evaluations of its accuracy. The main simulations included four different morphological scenarios, in which the parameters of densification and verticalization were changed. As result, it was identified that the scenario of greatest verticalization presented the lowest values for both Ta and TRM, reaching a difference up to 1°C for Ta at 15h, and up to 27°C for TRM at 9h, both linked to the standard scenario according to the current condition. This contrast was nearly related to the direct incidence of the radiation. Therefore, the scenarios more shaded by buildings indicated lower temperatures at the street level. However, the same scenarios, due to the fact that they were denser, and thus composed of a greater quantity of construction materials, had their cooling hindered toward the energy balance process, apart from having influenced the wind distribution and velocity, outlining a decrease of these values in most of the analyzed area.
Análise do comportamento dos pilares mistos considerando a utilização de conectores de cisalhamento
(Universidade Federal do Espírito Santo, 2002-09-08) Bianchi, Flavia Regina; Sá, Pedro Augusto Cesar Oliveira de; Coelho, Luiz Herkenhoff; Menandro, Fernando César Meira; Rodrigues, Francisco Carlos
The steel-concrete composite structures are systems that involve the interaction of structural steel components with concrete elements to resist external forces. This interaction between steel and concrete should be guaranteed to ensure that loads are supported. As such, adhesion tensions between the concrete and the steel should not be exceeded. In cases where they are, the use of shearing connectors becomes necessary. The influence of the use of shearing connectors in composite columns is greatly undervalued in the majority of scientific papers, with its use recommended only in situations of high vibration. In this paper, the behavior of composite columns is analyzed with the use of shearing connectors taken into consideration through numerical analysis using Ansys programming and based on the finite element method. To achieve this, an ideal model that reflects the situation was adopted permitting as study of the element, the load, and the contour conditions adequate for usage. Composite columns with and without shearing connectors were modeled. A load was applied to each model with varying eccentricity to create an interaction curve defining the moment of flexion in function of normal force. From the interactive curves that were constructed, the importance of the use of shearing connectors was analyzed. This analysis compares results to data supplied by EUROCODE 4(1994) and the influence of different values for maximum adhesion tension of the last load of the composite column.
Análise do planejamento ferroviário: uma abordagem utilizando simulação de eventos discretos
(Universidade Federal do Espírito Santo, 2016-08-15) Faria, Carlos Henrique Fernandes de; Cruz, Marta Monteiro da Costa; Morais Neto, Gregório Coelho de; Lopes, Luiz Antônio Silveira
The growth and the search for the rail transportation over the past few years make logistics decisions impacting on the business of the companies. Also, logistics has a fundamental importance and considerable cost and then receives special attention to managerial level. In the railway, changes in the long and medium-term system infrastructure as the construction of crossing yards, duplications or triplications on the track, the improvements of the rail to increase velocity of the compositions , as fixed costs and short-term decisions, such as the conservation of the wagons and locomotives, fuel expenses and the operacional workers necessary for efficient operation, require high costs and investments. Thus, the analysis need special attention in how they are made and then, what tools are using for decision making. In this context, the study aims to develop a discrete event simulation tool supply chain closed loop iron ore, capable of supporting analysis in the three planning levels. At the strategic level, with the perfect amount of setting wagons on the railway to make the projected volume in the long term and increase the rail capacity with the integration of investment projects in duplicate and simple railway. At the tactical level, the definition of railway stretch capabilities using dynamic simulation. And at the operational level, with the definition of the best maintenance strategies programmed permanent way that impact least some variables as the transit time and capacity. As a result, it was observed that the results obtained by the developed simulation tool are well adherent to the real system, bringing answers with low standard deviation and error rates when considering an accuracy in the results of 95%.
Análise e dimensionamento de lajes lisas protendidas sem aderência
(Universidade Federal do Espírito Santo, 2015-09-25) Carneiro, Anselmo Leal; Luchi, Lorenzo Augusto Ruschi e; Ferreira, Walnório Graça; Alves, Elcio Casimiro; Souza, Rafael Alves de
This report is proposed to present the resolution of a post-tensioned flat slab set with unbonded tendons, mainly covering layouts of tendons, calculation models and design strips options for floor analysis. The dimensioning regarding the ultimate limit state and service is based on NBR 6118:2014, however, there are some requirements from ACI 318-11 and ACI 423.3R-05, which show relevance towards this report aim. The dimensioning is restricted to flexion, not including the punching shear effect. The slab analysis occurs by means of grid analogy, in terms of the commercial program CAD/TQS, as well as multiple frames’ method regarding the FTOOL program. Both the grid method and frames, the inserting of all operating loads occurs, including the equivalent post-tensioned loads. It was concluded that the banded and distributed tendon layout presented advantages in relation to distribution of bending moments and deflections of the slab. The balancing for 60% of the dead load resulted in partial post-tension, but since cracking occurred only near the supports, the deflection analysis considering gross inertia proved enough. The difference in reinforcement consumption between calculation models was up to 22%.

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