Engenharia Civil

URI Permanente desta comunidade

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

Programa de Pós-Graduação em Engenharia Civil

Centro: CT
Telefone: (27) 4009 2146
URL do programa: http://www.civil.ufes.br/pos-graduacao/PPGEC

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Agora exibindo 21 - 40 de 295

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.
Logística lean : análise de correlação entre os desperdícios lean e as atividades logísticas
(Universidade Federal do Espírito Santo, 2011-07-05) Martins, Anne Francine de Souza; Cardoso, Patrícia Alcântara; Bertolde, Adelmo Inacio; Có, Fábio Almeida; Pizzolato, Nelio Domingues
The use of the lean manufacturing system is well known, but its application in logistics is a recent practice that can bring many benefits such as improved quality and productivity, minimize costs and reduce waste in processes. This study has the target to analyze the existence of correlation between the seven types of lean waste (overproduction, processing, storage, transport, handling, waiting and defects) and the primary activities of the logistics (order processing, inventory and transportation). To rescue the theoretical work, this dissertation begins with a literature review on the key concepts covered in the survey: logistics, lean thinking, lean logistics and performance indicators. To achieve the proposed objective was chosen the case study (carried out in a company providing road transportation of cargo). As an instrument of data collection used the semi-structured interview based on a preestablished, indirect observation, analysis of records and documents of the company studied and the preparation of flow chart of current value. For the treatment of data we used structural equation modeling, adopting the method of application of Hair et al (2009) suggests a process in which development of six stages. The existence of the correlation was evident in the correlation matrix and change model, in which new relationships were made and provided new adjustment indicators, obtaining a satisfactory model.
Avaliação da eficiência na captação de investimentos turísticos nas rotas turísticas do Espiríto Santo utilizando análise envoltória de dados
(Universidade Federal do Espírito Santo, 2011-07-08) Baldo, Josiane; Cruz, Marta Monteiro da Costa; Bertolde, Adelmo Inácio; Mello, João Carlos Correia Baptista Soares de
Tourism becomes a sector of more important time for the economic and social development of a country, contributing for the reduction of disparity of the regions and favoring for its growth. The transport service, as well as road infrastructure is essential part of the tourism in order to promote movement of tourists to the intended destination. The economic and social importance of the tourism sector has given rise to the need to study methods that can measure the power of attraction of their tourists destinations, beyond the efficiency in attracting investment in tourism in relation to investment in roads leading to these destinations. This paper presents a dissertation proposal which aims to apply the general methodology of Data Envelopment Analysis to measure the efficiency in the capture of Tourism Investment in relation to Investment in Highways in Tourist Routes of the Espírito Santo, and thus assistance the government in making decisions so that minimum standards of quality of road infrastructure and tourism are warranted to users. For this study were analyzed 87 stretches road linking Vitória to each urban community that compose these Courses. The stretch were divided into two groups due to the difference in the traffic volume with the primary reason the double track. Analyzes of the two groups and of the results achieved were made, and finally the conclusion of this paper is presented with proposals for future works.
Desenvolvimento de um modelo de simulação para identificação de gargalos na cadeia de suprimentos de uma empresa de mineração
(Universidade Federal do Espírito Santo, 2011-08-25) Oliveira Júnior, Roberto; Cruz, Marta Monteiro da Costa; Cardoso, Patrícia Alcântara; Saliby, Eduardo
The objective of this work is to develop a methodology to identify bottlenecks in the supply chain of inputs for the mining industry, more specifically to the process of pelletizing or agglomeration of fine iron ore pellets. This methodology is based on computer modeling and simulation of supply chain and the definition of appropriate indicators to assess their logistics performance. A model of discrete event simulation was developed to represent the current configuration of the supply chain, focusing on highlighting the main processes that comprise it. Taking as a base, variations of the model were built in the form of experiments, to evaluate and verify the effectiveness of alternative configurations in different possible scenarios for the whole system. The importance of the proposed theme is the lack of academic research focusing on the Brazilian mining sector and, more specifically, the input supply chain of production processes involving suppliers and customer. The current academic collection is more focused on the process of distribution of finished products, involving producers, wholesalers, retailers and end customers. The results obtained in the experiments proved prescient when confronted with reality, the proposed methodology is developed and proved effective as a tool to support analysis and decision making in such studies.
Industrialização na construção civil : uma contribuição à política de utilização de estruturas pré-fabricadas em concreto
(Universidade Federal do Espírito Santo, 2011-09-05) Spadeto, Tatiana Freitas; Oliveira, Marcel Olivier Ferreira de; Coelho, Luiz Herkenhoff; Louzada, Desilvia Machado
The Brazilian civil construction has grown effectively in the last decade due to the increased demand combined with the government social programs, in order to improve infrastructure and reduce the housing deficit. Another factor related to such growth is that Brazil shall host big sportive events, and it has been prepared to do so. As a result, the country has become a construction site. Although the growth production goes fast, its quality improvement does not follow the same standard. The construction techniques commonly used in Brazil are obsolete though some buildings are built with advanced technology. This study leads to a constructive technique, the precast in concrete, which aims to promote the rationalization and industrialization of civil construction, aiming to gain speed and quality in construction among other benefits. A short historical in building activity is presented from pre-history to the current Brazilian construction. Since then, its characteristics are analyzed, and we describe the precast in concrete within its advantages, as well as some aspects of its production and application. From that point, are listed and analyzed some aspects that have caused obstacles to greater use of industrialized building systems, the precast concrete system. Issues as previously presented are related to segments which are directly related to civil construction, the public sector, the productive sector and the professional sector. For each segment functions will be presented in this important sector. Finally, some proposals are presented in the areas of public policy, sustainability and quality of the final product in pursuit of providing the expanded use of precast concrete system.
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.
Proposta de um modelo matemático para o problema dial-a-ride aplicado ao transporte de cadeirantes
(Universidade Federal do Espírito Santo, 2011-09-16) Rodrigues, Patrícia Perretto; Resendo, Leandro Colombi; Rosa, Rodrigo de Alvarenga; Morais Neto, Gregório Coelho de; Ribeiro, Glaydston Mattos
Problems that deal with wheelchair users’ public transportation are often solved by Dial a Ride Problem (DARP) with time window (Time Window – TW). The goal of this type of problem is the minimization of the operation cost, in other words, the ride time respecting constraints like time windows for pickup and delivery of each user, the number of vehicles available and each vehicle capacity. This thesis proposes an exact Mixed Integer Linear Program model to solve the DARPTW. In order to apply the model in a real application, the model was tested with data provided by the Vitória City Hall Infrastructure and Transportation Secretary. The model was implemented using CPLEX software and the results showed that instances up to 20 wheelchair users’ can be solved optimally. Moreover, it was done an analysis for fleet used.
Estimativa de recalques de sapatas apoiadas em solos arenosos : uma abordagem probabilística
(Universidade Federal do Espírito Santo, 2011-10-25) Bungenstab, Felipe Carvalho; Ribeiro, Rômulo Castello Henriques; Bicalho, Kátia Vanessa; Dantas, Bruno Teixeira; Aoki, Nelson
This research discuss about probabilistic settlement analysis of footings in sands, focusing on the load curve (estimated settlements). For this purpose, three methodologies that take the First Order Second Moment (FOSM), Second Order Second Moment (SOSM) and Monte Carlo Simulation (MCS) methods for calculating mean and variance of the estimated settlements using the equation proposed by Schmertmann (1970) are discussed. The resistance variability curve (limit settlements) is assumed to be constant for some specific values. The deformability modulus (ESi) is considered varying according to the division of the soil into sub-layers and it is analyzed as the only independent random variable in process. As an example of the application of these methodologies, an unreal simplified case work in state of Espirito Santo, Brazil, on the use of compaction piles of sand and gravel, driven by Franki-type equipment, for densifying marine sandy soil, is discussed and evaluated. Results of the simulations indicate that there is significant similarity between SOSM and MCS methods and that the FOSM method underestimates the results due to the non-consideration of the high orders terms in Taylor expansion series. It has been also observed that the depth which the major variance contribution occurs is dependent of the ESi values in the layer analyzed, with strong influence of the IZ distribution factor, from Schmertmann (1970). The proposed probabilistic analyses may contribute to the knowing of the uncertainty in settlement estimations that can lead to more safety geotechnical design.
Revestimento de piso com porcelanato: estudo sobre especificação e execução baseado nas percepções dos profissionais envolvidos
(Universidade Federal do Espírito Santo, 2012-03-23) Muniz, Andreia Fernandes; Tristão, Fernando Avancini; Bauer, Elton; Gama, João Luiz Calmon Nogueira da; Vieira, Geilma Lima
The Brazilian ceramic tile stands out in national and international scene with a production of 753.5 million square meters and a domestic consumption of 699.60 million square meters in 2010. Growth in production and consumption, respectively, 32.57% and 58.14% compared to 2005 (ANFACER, 2011). In this context relates to the porcelain, whose production in 2010 was 8.0% (60 million square meters) of the total production of ceramic plates. In 1999 this index was approximately 0.8% (Menegazzo et al., 2000). This growth is associated with its production process and its technical and aesthetic characteristics, which made it a suitable option for specifying different types of works. However, the specification of the porcelain is not yet understood by those involved. Furthermore, the shape is the same laying of the tiles, which can lead to pathology. On porcelain, the objective is to demonstrate how the specification is made by manufacturers in catalogs, how to evaluate the specification and use of catalogs by design professionals, know how to market and see what the problems in implementing the flooring with porcelain. Expected to contribute to the adequacy of standards catalogs, making the query tools in the acquisition of the coating by the consumer and the stage of specification, made by design professionals. For the execution stage, attest to the need to develop a specific standard for implementation of the porcelain coating, suitable for the specific properties of porcelain. The methodology includes review of the state of the art and field research through questionnaires, personal interviews with the professionals involved. The survey results show that the catalogs are incomplete, design professionals use the experience of sellers to specify the execution of the work is flawed, the settlers are not qualified to perform standard and ceramic coating needs to have specific recommendations for implementation of porcelain.
Potencialidades do aproveitamento do resíduo de estação de tratamento de efluentes do processo de lapidação do vidro sodo-cálcico na produção de concretos
(Universidade Federal do Espírito Santo, 2012-03-30) Antônio, Aline Pignaton; Tristão, Fernando Avancini; Gama, João Luiz Calmon Nogueira da; Machado, Desilvia Louzada; Lima, Geilma Vieira; Oliveira, Marcel Olivier Ferreira de
The search for the reuse of waste generated in the rapidly growing urban centers in order to save natural resources, has remained fairly constant, both in the context of preventing the exploitation of resources and waste disposal on the environment. The main objective of this study is to use the waste from the treatment plant effluent in the process of cutting glass soda - calcium as a partial substitute for cement in concrete production. The substitutions on the weight of cement by the residue used in powder form with a particle size of about 38 µm, followed proportions of 0, 5, 10, 15 and 20% for all tests included in this study. First, cement pastes were studied for determining the expansion. The fresh concretes were subjected to slump tests and tests for determination of incorporated air content, density and water exudation, according to the Brazilian Standards. To determine the mechanical properties of the hardened concrete steel-molded cylindrical specimens were produced, with diameter of 10 cm and 20 cm height, tested for compressive strength and tensile strength at ages 3, 7 and 28 days and modulus of elasticity at the age of 28 days. Statistical analysis of data obtained allowed establishing that the test results of compressive strength showed significant variation and were subdivided into three heterogeneous and distinct groups, while the results of other tests showed no significant variation and homogeneity between the groups. Mixtures with more waste had mechanical strength reduced, except for the modulus of elasticity, which showed appreciable upward trend with the highest levels of replacement. Still, the strength results obtained meet the current Brazilian Standards for structural concrete. Samples of cement pastes and hardened concrete were examined by scanning electron microscopy (SEM) and energy dispersive spectrometry (EDS). Crystalline inclusions of calcium hydroxide could be noticed at different levels for each sample.
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.
Engenharia simultânea: planejamento e controle integrado do processo de produção/projeto na construção civil
(Universidade Federal do Espírito Santo, 2012-04-10) Pedrini, Manuela Kautscher; Alvarez, Cristina Engel de; Ferreira, Claudio Lima; Gama, João Luiz Calmon Nogueira da; Alvarenga, Augusto
The term Concurrent Engineering (CE) designates several concepts with the purpose of optimizing the time spent in the production of manufactured goods. Although this term has not been incorporated in the construction industry, studies about the management of building projects incorporate many of its ideas. The goal of my work is to discuss the application of CE within Civil Engineering, more specifically to study its suitability in the projects of the construction of buildings and to propose a framework to apply CE’s concepts in the design phase of the project. The motivation of my research derives from the current scenario of the construction industry in Brazil, in which construction companies have been searching for technological innovations in the process of developing new products. I used two case studies to assess the current state of the design process. Questionnaires and technical summaries served to identify the phases more likely to be optimized by CE, and to pinpoint the difficulties in applying CE. Results indicate that there is space to improve the new product development process, and that the adoption of CE is an alternative to provide such improvements.
Cascalho de perfuração de poços de petróleo e gás. Estudo do potencial de aplicação em concreto
(Universidade Federal do Espírito Santo, 2012-05-04) Fialho, Poline Fernandes; Tristão, Fernando Avancini; Nunes Filho, Evaristo; Gama, João Luiz Calmon Nogueira da; Vieira, Geilma Lima; Dal Molin, Denise Carpena Coitinho; Marconi, Flávia Maria
The drilling of petroleum wells generates many residues such as waste fluids and drill cuttings. The management of those drilling wastes has been a problem to the petroleum and gas industry not only due to the significant amount of residues generated but also due to the presence of both organic and inorganic contaminants in their composition. Studies for the reuse of drill cuttings in building materials are recent. They show possible alternatives of use of this material such as in pavement sub-base layers, in ceramic materials, and in cement-based materials. This research aimed to evaluate the behavior of two types of drill cuttings as a replacement and as an addition in unarmed concrete. Laboratory tests were performed to characterize the materials used in the concrete fabrication, in particular the drill cuttings, as well as control testing in concrete technology. The obtained results in this research showed that the interactions of drill cuttings with cement-based materials are related to their previous characterization. The replacement of sand by drill cuttings from the first phase of well drilling in the concrete mixture significantly changes the rheology of fresh concrete. The proportions tested did not compromise the concrete mechanical properties. Changes in concrete microstructure were only observed in the concrete samples with the addition of drill cuttings from the third phase of well drilling process. Those have become more porous and the formation of hydrated compounds occurred more slowly. The method of qualitative detection of free chloride did not identify chlorides in the concrete samples. Finally, it can be concluded that it is possible either the replacement of drill cuttings in concrete considering the levels tested in this study.
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 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.
Requisitos de iluminação natural nos sistemas de avaliação de edificios e impactos energéticos em edificações comerciais no Brasil
(Universidade Federal do Espírito Santo, 2012-07-09) Santos, Laila Souza; Alvarez, Cristina Engel de; Fardin, Jussara Farias; Krause, Claudia Mariz de Lyra Barroso
In the last decades, many countries started certifying buildings with a supposed superior environmental performance. In Brazil, the use of building assessment systems originally developed in countries with their own construction practices, energy, geography and climate conditions, has generate a lot of criticism in academia. An example would be the exigency, in Brazil, that sustainable buildings were to meet the daylight requirements of assessment systems proposed for sites where the availability of daylight is considerably lower than it is in Brazil and where the demand for heating is real in winter times. This work started from the premise that the application of these systems could encourage the construction of energy-inefficient buildings in Brazil, caused by the introduction of excessive daylight in architectural interiors. Thus, the aims here consisted of evaluating the energy impacts of meeting the daylight requirements set by imported systems with possible application in Brazil, such as AQUA, BREEAM and LEED. The methodological procedures included development of parametric models with different solar orientations, window-to-wall ratio (WWR), shading devices and protection angles. These models were simulated in DIALux and DesignBuilder softwares in five brazilian cities, in order to identify the models meeting the daylight requirements in building assessment systems and to measure their energy impacts when subjected to different brightness of the sky. The results allowed to identify that methodologies based on daylight factor (DF) as an indicator of daylight use does not favor the proposition of more energy-efficient buildings and that, in general, there is little consensus on what is considered appropriate for luminous performance, since only one third of the models meet the requirements in all assessment systems investigated. Among them, all simuntaneously presented WWR of 100% and the use of shading devices, which increase the energy consumption spent with electric lighting and air conditioning by about 20% when compared to similar models with WWR of 50%, indicating that rating systems do not necessarily represent improvements in environmental performance of buildings.
Pasta de gesso com incorporação de resíduo de gesso e aditivo retardador de pega
(Universidade Federal do Espírito Santo, 2012-08-10) Trovão, Ana Paula Milagres; Tristão, Fernando Avancini; Vieira, Geilma Lima; Tubino, Rejane Maria Candiota; Teixeira, Jamila Emi Sudo Lutif
The use of plaster in civil construction generates a large amount of waste, but it is a material that posses properties that makes it a highly competitive product. The main cause of the generation of this waste is the rapid hardening of the pastes. The incorporation of waste gypsum into the gypsum pastes results in an acceleration of the hardening process, which might increase the volume of residues generated. This dissertation aimed to develop procedure to incorporate the gypsum residue into plaster pastes without compromising the paste mechanical properties and, especially without accelerating its hardening process. Tests have been developed to evaluate the plaster pastes setting time, consistency, workability and temperature reading in the plaster pastes in the fresh state and evaluate the hardness and axial compressive strength in the hardened state. Tests results showed the viability of the incorporation of 5% gypsum waste in substitution of gypsum in the plaster paste when combined with borax retardant additive, which promoted extension of the workable time of the paste and an increase in the pastes mechanical properties
Estudo das curvas de retenção e condutividade hidráulica estimadas pela equação de van Genuchten (1980) para diferentes tipos de solo
(Universidade Federal do Espírito Santo, 2012-10-25) Gonçalves, Fernanda Vescovi; Bicalho, Kátia Vanessa; Oliveira Filho, Waldyr Lopes de; Pires, Patrício José Moreira; Dantas, Bruno Teixeira
The van Genuchten (1980) equation has been widely used in the literature to represent analytically the soil water retention curve, and there are several published database tables which allow estimate the van Genuchten (1980) parameters (VG parameters) for different soils and regions. The equation enables one to derive closed-form analytical expressions for the unsaturated hydraulic conductivity function using Burdine (1953) and Mualem (1976) models. The objective of this dissertation is to study published database tables of the retention and hydraulic conductivity functions for different soils (Wosten et al.; 1999; Schaap et al., 2001; Hodnett and Tomasella, 2002; and Gerscovich and Sayão, 2002), and quantify the variation of VG parameters with the grain size distribution of these soils. The different experimental methods, the large variability of soils, and the lack of complete information of the soil properties of the investigated data, and the lack of physical meaning of VGparameters did not allow to define functions to quantify the variation of VGparameters with the grain size distribution for the investigated soils. The results suggest that there is no dependency between the VG parameters and the fine content of the investigated silty sand soils when the percentage of fines is such that it fills all large grains voids. In this case, the limited classification based only on soil texture can not be used to estimate the VG parameters. The variation of saturated hydraulic conductivity with fines content provides a useful means of assessing the existence of the dependency between the VG parameters and the soil texture. For the silty sandy soils evaluated in this study, when the fines content is higher that 30% there is no dependency between the VG parameters and the fines content. It is also observed that the soils that do not exhibit a significant difference in their saturated hydraulic conductivity values may exhibit large variations in their unsaturated hydraulic conductivity values depending on their fines content. For high suction values, the relative permeability of the soil specimens with 10% of fines content can be up to 1016 times lower than that of the soil specimens with 90% of fines content.
Arquitetura institucional de ensino superior: ações sustentáveis projetuais baseadas nas categorias do LEED Schools NC-V3
(Universidade Federal do Espírito Santo, 2012-10-30) Bastos, Celso Silva; Gama, João Luiz Calmon Nogueira da; Oliveira, Marcel Olivier Ferreira de; Barcelos, Fabrício Broseghini
This study consists in an approach to sustainability in construction, analyzing the concepts of sustainable development and proposing solutions that aim the reduction of environmental impacts, efficient use of materials and water consumption in the building sector. The objective of this research is to expound the sustainable actions applied to a project adopted as an example, referring to a building for educational use, in a qualitative way, emphasizing the use of a system that reuses the water from air conditioning condensation system proposed by the author, based on the certification tool and criteria of LEED Schools NC - v3, without, however, having the purpose of achieving scores. Thus, the author sought to contribute to reducing environmental impacts through the construction of projective procedures adopted for the construction of a building of higher education in the city of Vitória, ES. In this work it will be presented models and sustainable concepts, programmed solutions and systems research in international, national and local buildings that achieve high environmental performance. Subsequently, assessment methodologies are described of environmental performance in the world. As an example, some school buildings environmentally certified cited will be mencioned and the results of their environmental performance will be evaluated. The results demonstrated that a considerable reduction in the consumption of water and energy can be achieved, in addition to improved productivity environments designed with materials with low volatile organic compounds and proper acclimatization.
Estudo da influência da interação solo-atmosfera nos perfis de umidade, sucção e temperatura de um subsolo não saturado
(Universidade Federal do Espírito Santo, 2012-11-22) Vivacqua, Gabriel Peixoto Derenzi; Bicalho, Kátia Vanessa; Pires, Patrício José Moreira; Dantas, Bruno Teixeira; Oliveira Filho, Waldyr Lopes de
The aim of the present work is to investigate the influence of the soil-atmosphere interaction on the soil moisture, suction and temperature profile of an unsaturated subsoil. It is also investigated the depth of the active zone , the region of the soil influenced by climatic changes. A soil-atmosphere interface numerical model is used to calculate the rate of evaporation from the soil, and a mass flow equation (liquid water - Darcys Law and vapour - Ficks Law) coupled with a heat flow equation (de Vries, 1987) have been adopted to determine the soil temperature, moisture and pore pressure profiles. For the numerical simulations is adopted a one-dimensional computer program which uses the Finite Difference Method for solving simultaneously the mass flow (liquid and vapour water) and heat flow partial differential equations. The analyzes uses a set of climate data from Mormoiron, France, between the years 2004 and 2005. During the analysis, soil parameters and climatic data were manipulated, and the results of the analysis were compared with reference cases. Among the conclusions, it can be mentioned: (a) a variation on the initial soil temperature profile (ITP) can affect the soil temperature profiles, especially in the deeper region where the soil temperature remains stable throughout the year; (b) the Albedo parameter can do affect the soil temperature profile, especially in the hot season (great solar radiation). During the winter, changes in albedo values has quite no influence in the soil temperature and water content; (c) the active zone in the study region has about 1.5 m. From this depth, the soil temperature, moisture and suction profiles becomes practically constant over the year; (d) the use of average values, as daily inputs, modify the depth of the active zone, suggesting that under extreme conditions the depth of the active zone, in a particular region, can be changed; (e) the intensity and distribution of the precipitation can affect the soil moisture and soil suction profiles

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