Mestrado em Geotecnia, Estruturas e Construção Civil (EECA)

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Avaliação de elementos de infiltração de águas pluviais na zona norte da cidade de Goiânia
(Universidade Federal de Goiás, 2008-08-29) Carvalho, Eufrosina Terezinha Leão; Gitirana Júnior, Gilson de Farias Neves; http://lattes.cnpq.br/4710728908810849; Sales, Maurício Martines; http://lattes.cnpq.br/2033708685029423; Sales, Maurício Martines; Gitirana Júnior, Gilson de Farias Neves; Vargas, Carlos Alberto Lauro; Carvalho, José Camapum de
The development of the urban environment results in an expansion of impervious ground surfaces that greatly affects the hydrological cycle in the cities. The objective of this research is to evaluate infiltration structures for the control of excess drainage at the origin of runoff. These structures are constructed with the purpose of minimizing the impact of impervious surfaces to the urban environment. An experimental field was established consisting of several infiltration structures, such as small-diameter pilot wells and real scale wells. The real scale wells used perforated concrete pipe casing and brick lining. Falling-head infiltration tests were carried out during 15 months, encompassing the dry and rainy seasons. The infiltration tests were undertaken with initial conditions that correspond to the natural water content at the time of testing. Additional tests were undertaken with previously flooded conditions, reproducing several consecutive rainy days. The monitoring of pilot wells along with real scale wells allowed the evaluation of project parameters obtained from pilot wells. The values of average infiltration rate of different infiltration wells were compared and the performance of the several structures was compared. Laboratory test were carried out for the determination of the hydraulic parameters of the ground profile, including the saturated hydraulic conductivity the soil-water characteristic curve. A numerical model for the simulation of infiltration wells was implemented using the software FlexPDE. Special boundary conditions were developed that take into account the transient relationship between the varying hydraulic head at the well walls and the total volume infiltrated during a test. The numerical simulations contributed for a better understanding of the infiltration mechanism, the influence of the hydraulic conductivity to the infiltration rate, and the determination of the wetting front and pore-water pressures during infiltration. A design criterion for infiltration wells was proposed using daily compensation, considering the daily water balance during 25 years, and the precipitation historical series of the site. The proposed design criterion makes possible the selection of the group of infiltration structures that meet the project goals. The design criterion also allowed the evaluation of the theoretical performance of wells designed using two conventional criteria
Retroanálise numérica da convergência de uma escavação subterrânea em rocha (caso estudo: TAJ UHE Simplício)
(Universidade Federal de Goiás, 2009-06-09) VISSOTTO JÚNIOR, Lucas Alberto; VARGAS, Carlos Alberto Lauro; http://lattes.cnpq.br/3816106720170772
Currently, the increasing demand for great workmanships in Brazil, had become an impediment for the development of Brazil. The Geotechnical Engineering is considered an essential tool, in great workmanships (hydroelectric power plants, subways, tunnels, etc.) supplying technical support for design and construction. In this context, the underground excavations in rock have increased too much. This work presents a study of the behavior of the closer of an underground excavation in rock, where it was considered as case study, Simplício hydroelectric power plant, located in the Paranaíba do Sul river, in frontiers of the States of Rio de Janeiro and Minas Gerais. By means of laboratory tests with samples of intact rock and survey mapping of discontinuities, was characterizes the rock mass. Establishing the principal geomechanic parameters and estimating the in-situ stress state of the rock mass, then was chose the geomechanical model and made a numerical simulation of the excavation process tunnel help downstream of tunnel 3. For the tunnel study was conducted a numerical axial analysis symmetry of the relaxation of the excavated mass on the distance from the face of excavation, to determine the moment of installation and simulate a support of the tunnel closer. For the carried out simulation, the rock mass behaved only in the elastic range, finding closer the results of the simulation, the results on the field by monitoring the tunnel. It was observed that for the degree of alteration of the studied mass, the rupture could occur for the rock as well for the discontinuities, depending on the wedges formed for the discontinuities families and the support type applied in the rock mass
Um modelo de gestão de resíduos sólidos: aplicação em indústria de artefatos e pré-moldados de concreto
(Universidade Federal de Goiás, 2009-09-04) MELO, Tatiane Medeiros; TUBINO, Rejane Maria Candiota; http://lattes.cnpq.br/5775852172717383; ARAÚJO, Daniel de Lima; http://lattes.cnpq.br/8801080897723883
The productive chain of the construction industry is responsible for many positive and negative impacts on the built environment. One of the negative impacts refers to the high amount of waste produced, which can be reduced through the industrialization of construction, that is, through the reduction of services at construction sites and transferring them to the factories. In this sense, the use of prefabricated structures may reduce the production of waste arising from the implementation phase of structures, such as molds and buttresses. However, if the production of the prefabricated elements in plants is not properly planned, the problems of waste production can be transferred from construction site for the industry environment. This fact was observed in some industries of artifacts and pre-molded concrete. The aim of this paper is to propose a methodology for solid waste management through the integration of the methodologies of environmental management system, cleaner production and suggestion already published of project management of construction waste envisaged by Resolution nº 307 Conama and applies this methodology in an industry artifacts and pre-cast concrete. For this, two processes of an industry of Goiânia were selected, which served as a pilot in the implementation of model solid waste management proposed. By implementing this model, it was possible to quantify the waste produced in the processes studied, as well as make significant improvements in its characterization, segregation, packaging, transportation and disposal through the implementation of opportunities for cleaner production highlighted. Moreover, mechanisms were created for the own employees were responsible for maintaining the proposed activities. As result of this study, a database about the chain of waste in the processes studied was produced, which can be used in future for the proposition of other opportunities for cleaner production in industry studied. Still, the methodology of waste management proposal can serve as a model for replication in other industries of artifacts and pre-cast concrete
Estudo de tratamentos com lítio no combate da reação álcali-agregado
(Universidade Federal de Goiás, 2009-09-11) CÂNDIDO, Wilson Ferreira; HASPARYK, Nicole Pagan; http://lattes.cnpq.br/4932240949129648
The alkali-aggregate reaction (AAR) is one of the deterioration processes of concrete that most affects the structures of hydroelectric plants, concrete dams and bridges. In recent years, the efficiency of lithium based compounds to mitigate RAA has been proven in both the prevention and repair of the affected structures. With regards to treatment, the main challenge nowadays is how to ensure the adequate impregnation of concrete with the lithium solution. Given this difficulty, the objective of this research is to investigate in laboratory conditions, the efficiency of various types of treatment, using a product based on lithium nitrate. The treatments sought to prevent or minimize the residual expansion of AAR, in particular the alkali-silica reaction (ASR), already under development in the concrete and mortar. The study was divided into two stages, the first one performed in concrete prisms, from an adaptation of the Brazilian standard NBR 15577-6/2008, and the second stage in mortar bars, from an adaptation of NBR 15577-4/2008. The treatments were performed after the specimens reached a predetermined level of defined expansion: 0.04% for the concretes and 0.18% for the mortars. In the case of the concretes, the treatments were electrochemical lithium impregnation and surface saturation with lithium, in addition to their respective reference procedures (impregnation and surface saturation with water). For the mortars, the situations tested were: vacuum impregnation with lithium, total saturation in lithium, surface saturation in lithium, water immersion and wrapping in plastic film. After each exposure/treatment condition, the specimens returned to the accelerated expansion attack process in order to evaluate the effectiveness of each treatment. The results demonstrated the efficiency of the lithium based composite to mitigate the residual expansion, both in the concretes as well as in the mortars, with a different behavior depending on the conditions used. The treatment that had the best efficiency in the concrete, under the applied experimental conditions, was the surface saturation of lithium, achieving a 90% reduction in the residual values of expansions at the end of the attack (73 days), taking as reference the surface saturation condition with water. The lithium electrochemical impregnation performed was able to mitigate the residual expansions, but only up to the age of 42 days after treatment, at which time the reduction was of 50%. In fact, at 73 days the expansions were similar to those of the untreated sample. All treatments with lithium performed in the mortars were able to mitigate the residual expansions at levels approaching reduction of expansion (about 87%), with the total saturation in lithium the most efficient condition.
Estudo da propriedade resistência superficial em revestimentos de argamassa
(Universidade Federal de Goiás, 2009-09-20) ALVES, Amália Silva; CASCUDO, Oswaldo; http://lattes.cnpq.br/3336749062812376; CARASEK, Helena; http://lattes.cnpq.br/3023241186996790
The lack of cohesion in mortar renderings corresponds to the loss of mechanical strength among theirs layers due to the weakening of particles bond, a fact which is reflected, among other events, by a low surface resistance of these renderings. Thus, poor surface strength of mortar renderings accelerates their degradation process, leading to a significant reduction in the level of their performance and leading to failures in the functions assigned to them. In this context, this basically experimental research aimed to study the property of surface strength in mortar renderings. So, was investigated the applicability of some test techniques, pendulum hammer, dynamometer traction and ultrasounds (by indirect method) to evaluate surface characteristics of the mortar renderings. In addition, were also evaluated the effects of moisture absorbed by the renderings, the influences of composition, air entrained content and application way in the surface strength of the mortar renderings. In this study, the experimental program was divided into two stages. In the first stage, were used: one mortar mixed (cement: lime: sand) and one industrial mortar (with air entrained content equal 20%) applied in one type of substrate (concrete surface - standard substrate ABCP) by compressed air projection, so that their produced coverings were tested under different conditions of moisture (oven-dry, dry environment, wet and saturated). In the second stage, were used: one mortar mixed (cement: lime: sand) and three industrial mortars (with air entrained content equal 20%, 30% and 40%) applied to the substrate standard in three ways (manually, by means fall box and by compressed air projection). Using statistical criteria, the main results have shown a significant effect of the four mentioned factors on the surface strength, in view of the testing techniques used. However, only showed no significant the effect of moisture in the hardness index.
Avaliação da capacidade de proteção contra a corrosão da arma-dura induzida por cloretos de concretos com adições minerais e inibidores de corrosão
(Universidade Federal de Goiás, 2009-09-28) LIMA, Marcelo Batista; HASPARYK, Nicole Pagan; http://lattes.cnpq.br/4932240949129648; CASCUDO, Oswaldo; http://lattes.cnpq.br/3336749062812376
Increasing the durability of concrete structural elements is primordial, especially those related to power generation in eolic areas that are subjected to the phenomenon of reinforcement corrosion. In this context, this study aims to evaluate the overall protection ability of concrete to the phenomenon of reinforcement corrosion induced by chlorides. To this end, it was adopted a statistical program based on a fractional factorial design in which the variables studied were as follows: the water-binder ratio (0.35, 0.45 and 0.55), the type of mineral admixture (silica fume and blast furnace slag at specific levels), the type of corrosion inhibitor (calcium nitrite, sodium nitrite and amine) and the level of corrosion inhibitor (minimum and maximum recommended by each manufacturer). In the concrete investigations, the tests performed were corrosion potential, polarization resistance and electrochemical impedance. Throughout the experiments, it was possible to testify the beneficial effect of reducing the water-binder ratio. It was also possible to prove the very positive effect of the incorporation of mineral admixtures, especially of silica fume. The satisfactory performance of various inhibitors evaluated was also verified, specially when concrete contains mineral admixtures. A parallel study was conducted to make a comparative analysis of inhibitors at the same range of concentrations (at solid levels of 0.76%, 2.21% and 3.66% of the compound on the cement mass), nevertheless this study have demonstrated that fixing contents for all inhibitor is not appropriated, and the recommended dosages by the manufacturer is the best condition. As the levels recommended by manufacturers, it was found that the higher percentages have not worked well for sodium nitrite otherwise, for amine and nitrite calcium, the higher levels implied better results. Regarding the tannin inhibitor also assessed in the parallel study mentioned above (related to specific inhibitors), its good performance related to corrosion inhibition happened just for the content of 0.76% (the lowest levels). For the other contents, it was verified anomalous results. These results demonstrated that each type of corrosion inhibitor has its optimal concentration for use in concrete. Based on a cost-benefit analysis and evaluating the increase in the concrete value for cubic meter (in R$) in the presence of inhibitors at the same contents, it was verified a relative parity prices among the tested nitrites and an extremely high cost of amine. However, when performing the same analysis but using the levels recommended by the manufacturers for each inhibitor independent, it was found that the large disparity in prices between nitrite and amine was reduced considerably. An assessment of technical and economic feasibility was also performed based on the efficiency of corrosion inhibition and cost per cubic meter of concrete mixtures that did not show a typical depassivation of their stell bar up to the attack age evaluated
Análise tridimensional de estabilidade de talude utilizando o método de equilíbrio limite aperfeiçoado
(Universidade Federal de Goiás, 2009-09-29) ADRIANO, Pedro Rogério Ribeiro; GITIRANA JUNIOR, Gilson de Farias Neves; http://lattes.cnpq.br/4710728908810849
The main objective of this research is to investigate a three-dimensional (3D) slope stability analysis technique using the enhanced limit equilibrium method. The other objectives are to evaluate the practical applicability of the 3D analysis method, to interpret the physical significance of 3D stress states to the stability of a slope, and to determine the relationship between two-dimensional and three-dimensional factors of safety. For that, a computer program called SAFE3D was developed. The computer program is used to calculate the three-dimensional factor of safety (FS3D) for pre-established slip surfaces with spherical or ellipsoidal shape. The computer program is based on the two-dimensional analysis method proposed by Kulhawy, combined with an extension of this theory to 3D conditions that is proposed herein. The method developed consists in determining the in-situ stress fields by means of an elastic 3D stress-strain analysis using the finite element method. The 3D stress fields are then used to calculate the normal and shear stresses along any pre-determined slip surface and to determine the value of FS3D. Two slope stability problems widely studied by other researchers were analyzed in order to validate the program SAFE3D. The first problem corresponds to a symmetric cohesive slope and the second problem corresponds to a non-symmetric slope with cohesion and friction. Excellent results were obtained, suggesting that the program SAFE3D is efficient, stable, and robust for the problems studied. The values of FS3D obtained herein are similar to the values presented by other authors using distinct methods of analysis. A parametric study was carried out considering the shape of the slip surface and the shape of the face of the slope, including concave and convex slopes. The results indicate that the values of FS3D are always higher than the two-dimensional factor of safety (FS2D) of the intermediate surface. The value of FS3D decreased for slip surfaces extended across the sliding direction and approached the value of FS2D. It was determined that the Poisson's ratio has an important influence on the FS3D. The value of FS3D increases with the increase of Poisson's ratio. This influence varies with the geometry of the problem and the treatment given to the cinematically inadmissible shear stresses. Finally, a 3D analysis of the historic case of Lodalen is presented. The results indicate that the FS3D at the time of the slide is slightly higher and approaches 1 if the less favorable shear strength parameters determined by previous studies are used. In this case, the values obtained for FS2D are considerably smaller than 1, thereby indicating the potential superiority of the 3D approach.
Avaliação das propriedades de transporte de massa contendo adições minerais
(Universidade Federal de Goiás, 2009-10-06) MENDES, Marcus Vinícius Araújo da Silva; CARASEK, Helena; http://lattes.cnpq.br/3023241186996790; CASCUDO, Oswaldo; http://lattes.cnpq.br/3336749062812376
The durability of reinforced concrete structures is damaged by the degrading action of the penetration of substances in the form of gases, vapors and liquids through the pores and cracks. It is known that water both in its pure form or containing dissolved ions such as chloride, sulphate, carbon dioxide or oxygen ions, can compromise the durability of concrete structures. In reinforced concrete structures at the marine environment, for example, the towers of wind power plants, this degradation can be more intense and accelerated. Thus, in the present study were analyzed concretes with different mineral additions (silica fume, blast furnace slag) and water / binder ratios (0.35, 0.45 and 0.55), with the objective to verify if the inside and cover thickness of concrete have some effect on the mechanisms of transport and also the effect of carbonation (only for concrete with w/b equal to 0.55) in the surface layer of concrete is important enough to make dificult the entry of aggressive agents in concrete. For this, the following tests to evaluate the mass transport in concrete were performed: capillary water absorption (NBR 9779:1995), water penetration under pressure (NBR 10787:1994), air permeability (method Figg), penetrability of chloride ion (ASTM C 1202: 2009), non-steadystate migration test (NT BUILD 492:1999). As a result, it was found that the mineral addition used generally provided an improvement in front of the concrete mechanisms of mass transport. In one of the properties, namely the diffusion coefficient (non-steady-state migration) of concrete with the use of silica fume and blast furnace slag, this has been reduced dramatically, around 11 times for the concrete with w/b equal to 0.55, when it is compared with concrete without mineral addition. It was observed that the inner region of concrete behaved better, in an unexpected way, than concrete cover region for some properties (capillary absorption, water penetration under pressure, penetration of chloride ions). From this conclusion, it can be said that the inner part of concrete is composed of transition zones (aggregated interface / mortar) exposed to facilitate the entry of fluids, gases and ions. About the effect of carbonation, this affected the capillary absorption and air permeability. The results led to explain that the clogging of the pores resulting from the product of carbonation (CaCO3), promoted the refinement of the pores, thus increasing capillary force and, consequently, increasing the capillary absorption. However, for air permeability this effect has damaged the passage of air through the surface layer. Finally, it is important noting that significant correlations were found among tests that evaluated the mechanisms of mass transport, namely, penetration of chloride ions and capillary absorption, diffusion coefficient (non-steady-state migration) and capillary absorption, permeability air and water penetration under pressure, penetration of chloride ions and the diffusion coefficient.
Viga composta com viga e laje pré-moldadas ligadas mediante nichos :análise via modelagem computacional
(Universidade Federal de Goiás, 2009-10-22) MELO, Matilde Batista; ARAÚJO, Daniel de Lima; http://lattes.cnpq.br/8801080897723883
In structural system of composite beams with slab and beam, both precast, it is necessary that shear stress is transferred from the slab to the beam through the interface to assure the composite action between beam and slab. This study has the objective of assessing the behavior of composite beams with slab and beam precast connected by pockets. For this, it was developed a computational model based on the Finite Element Method using the commercial software DIANA® 9.3, which make possible the analysis of interaction between shear stresses transferred by interface to precast beam and shear stress on the precast beam due to vertical loading. In the analysis, the behavior of these beams was compared with the behavior of beams with continuous connection, usually employed. In addition, the type of beam-slab interface (with or without shear-key) was analyzed. It is tried from this analysis to confirm some models presented in the literature for design composite beams connected by pockets. Usually, the models used to design of reinforced concrete beams to shear are slightly modified to design the composite beams connected by pockets. The results show that, in fact, there is an increase on the shear stress of precast beam due to a discrete connection provided by pockets
Bacia hidrográfica do córrego granada – Aparecida de Goiânia – GO: os processos erosivos e a dinâmica espacial urbana
(Universidade Federal de Goiás, 2009-10-29) Aguiar, Vinicius Gomes de; Romão, Patrícia de Araújo; http://lattes.cnpq.br/0188184635964559; Romão, Patrícia de Araújo; Sales, Maurício Martines; Guimarães, Renato Fontes
The basin of the Granada stream, with approximately 15 km2, is placed in the central part of the Aparecida de Goiânia - GO, located in the region metropolitan of Goiânia, to the south of the Goiânia. This basin limits for the coordinates east 682,000 and 688,000, and 8.145.000 north 8.139.000m and, MC -51º, South hemisphere. Aparecida it presents a confusion growth, intensified from 1970, configuring a big horizontal urbanization, with demographic empty in the interior of the city. The ambient impacts in the city if had evidenced in the measure that the city if to expand on the deep ones of existing valleys, as in the case of the near occupations to the Granada stream. All these not calculated uses of lands in the basin, that is, without looking for to establish tools and methodologies of conservation, come back toward the ambient-urban planning, had induced negatives occurrence of the ambient impacts and partner-economic, mainly the deflagration and the acceleration of erosive processes, generally in direction to the courses of the rivers, as it is the case of the soil erosions that leave the vulnerable inhabitants the catastrophic accidents. Soon, to attain the central objective of this research, that to be understand as the urban space dynamics speeds up or to give rise to, start the erosive processes in the basin of the Granada stream, had been elaborated map of declivity, soil in-situ, occupation of lands and bending of the sources, from digital modeling of fine altimetric data with survey of field by means of topographical receiver GPS and images of satellite of diverse sensors. The study area is characterized for the ground predominance of the type Ustox soils, that had been classified how much its erodibilidade, by means of the laboratorial assay Inderbitzen, adapted in the scope of this research. With the assay it was possible to determine the loss of ground soil, for the action of the superficial draining in indeformados bodies of test. Although low the declivity of the land, the basin of Granada possess almost rectilinear, associates the deep and fragile ground, what it more than induced the to be published 30 erosions.
Análise da interação solo-estrutura em edifícios sobre estacas
(Universidade Federal de Goiás, 2009-10-29) ARAÚJO, Adrianne Carvalho de; SALES, Maurício Martines; http://lattes.cnpq.br/2033708685029423; PRADO, Ademir Aparecido do; http://lattes.cnpq.br/4118518363912053
The joined structure-foundation analysis of buildings is one of the studied themes of Soil- Structure Interaction (SSI). In this research, a numerical tool was developed using the Matlab program to evaluate the soil-structure interaction in buildings, where the problem has been studied in the last years, but has not became a current practice in civil engineering. The developed program, here named as AIEFE, predict the settlement using the Aoki and Lopes (1975) method, using as input data the reaction loads of building columns, calculated in any subroutine of spatial-portico analysis. The commercial program TQS was chosen as this subroutine in the present research. The found foundation settlements were converted in stiffness values and, then, inputted again in the structural analysis, predicting new settlements, but no more considering the foundations as fixed points . The method is iterative, aiming to reach the settlement (or load) convergence. Two examples of buildings supported by piled foundations were analyzed. The first one presented an almost square plant and the other one was typically rectangular. The SSI effects were analyzed in terms of column loads and also stiffness and foundations settlements during the constructive process of the 15-levels studied cases. During the construction of the first building levels, it was observed a greater load and settlement redistribution, due the lower structural stiffness. Using the foundation stiffness instead of settlement values was considered as an efficient process of convergence. It was also observed that the non-linear foundation behavior had a great influence in the structure load redistribution, even on advanced construction stages when the structure stiffness has a great value.
Análise do comportamento mecânico de um solo expansivo da província petrolífera de Urucu-AM para fins de pavimentação
(Universidade Federal de Goiás, 2009-10-30) SOUZA, Leonardo Sebastiao de; REZENDE, Lilian Ribeiro de; http://lattes.cnpq.br/9258692609398794; GITIRANA JUNIOR, Gilson de Farias Neves; http://lattes.cnpq.br/4710728908810849
The establishment of transportation infrastructure is critical to the development of the Urucu- AM region, a newly developed oil exploration area in the Amazonas state. The construction of such infrastructure is challenging due to the lack of suitable materials for the construction pavement base and subbase courses and adverse weather conditions, with alternating heavy rainfall and drought periods. Besides the shortage of suitable granular material, the presence of expansive soils is often verified. The presence of expansive soils associated with inadequate moisture content during compaction, results in the occurrence of cracks in the pavements, drastically reducing its performance and lifetime. A quantitative understanding of this type of problem requires the analysis of the interaction between the unsaturated soil surface and the atmosphere and the study the mechanical behavior (stress-strain) of unsaturated soil. Such understanding requires the determination of the variations in soil moisture and total volume. The quantification of tensile stresses also requires the establishment or evaluation of the constitutive relations of the unsaturated expansive soils involved. Experiments were conducted in the laboratory with the objective of characterizing the hydraulic and mechanical behavior of expansive soils from Urucu-AM. Chemical, physical and mineralogy characterization tests were carried out for the soil. Geotechnical characterization and Proctor compaction tests and compression were performed. To study the soil in the unsaturated condition, the main focus of this work, tests were performed using the filter paper technique and the axis translation technique under oedometric conditions. For the suction controlled oedometric tests, a cell developed specially for this purpose was employed. The oedometer allows for the independent control of vertical stress and matric suction and the monitoring of the variation of moisture and total volume study. State surfaces for void ratio, degree of saturation and gravimetric moisture content were determined. The results obtained show the expected mechanical behavior of the soil under wetting paths.
Uma nova metodologia de extrapolação dos dados da prova de carga dinâmica: MES-CASE
(Universidade Federal de Goiás, 2010-02-26) ALVES, éder Chaveiro; SALES, Maurício Martines; http://lattes.cnpq.br/2033708685029423; VIANA, Paulo Márcio Fernandes; http://lattes.cnpq.br/4545240150317474
Since 1983, when the experiment of dynamic load has been plunged in Brazil, the execution of this kind of experiment has become a common practice in foundation sites on precast inserted piles. In many cases the experiment of dynamic load doesn t mobilize the ultimate strength of the tested pile; the causes of these events may be due to: the available equipment at the site isn t capable of obtaining enough kinetic energy to mobilize the ultimate strength; the structural element presents ruptures; the client desire of not mobilizing all the ultimate strength; among others. Knowing the necessity of determining the ultimate strength in order to adapt the construction to the security factors required by NBR 6122/1996, this essay pursuits developing a methodology of extrapolation of the curve of mobilized static resistance versus the maximum displacement obtained through the dynamic load proof (dynamic load experiment of crescent energy), applying the Simplified Method CASE, to inserted precast piles. Studying 21 (twenty-one) proofs of dynamic load (PDL), an extrapolation methodology has been developed entitled as Simplified Extrapolation Methodology of CASE Method (SEM-CASE). The methodology is based on the criteria of complementary energy, presented by Aoki in 1997. The results have demonstrated that the method SEM-CASE has presented itself as easy manipulation. The estimated values of ultimate complementary strength calculated by the SEM-CASE has presented pretty close to the measured values, existing only one pile which presented a value error bigger than 10%. The estimated values of ultimate pile strength, obtained by the SEM-CASE, showed themselves similar to the measured values, also having a value error inferior to 10%. The exponential function has obtained better results of adjustment coefficient (R2) related to the points of the curve of mobilized static resistance versus the maximum displacement measured in the dynamic load proof. Besides, applying model selection criteria was obtained that the exponential function is more efficient to estimate the curve of mobilized static resistance versus the maximum displacement than the hyperbolic and parabolic functions.
Análise numérica da influência dos segmentos grauteados na interação entre paredes de alvenaria estrutural com blocos de concreto
(Universidade Federal de Goiás, 2010-04-06) REIS, Paulo Francisco de Oliveira; PRADO, Ademir Aparecido do; http://lattes.cnpq.br/4118518363912053; KHOURI, Magid Elie; http://lattes.cnpq.br/6016910773799021
Structural masonry is one of the oldest building systems used by man. With technological advance, its use has become more and more frequent for providing rationality and economy to the building. For that reason, the research centers have tried to get to know it more precisely, especially in Brazil, where the system differs from other countries, prevailing the use of not armed or partially armed masonry. The studies conducted aim to know, primarily, the materials used and the analysis of their structural behavior. Even though, there are still masonry structural aspects that haven t been totally clarified. Based on that principle, the purpose of this work was to accomplish an investigation about the influence of grouting segments in the interaction between walls, with the utilization of isolated panels of three, five and seven walls and a multiple pavement structure, developed by computational modeling in finite elements. For the analysis of the results, check the profile of the distribution of normal vertical tensions and the absorption of applied loading. In this way, it is realizable that in some cases the grout causes significant interference, as in the holes of the bricks, while in others, its participation is almost despicable. An example is the grouting of the braces.
Comportamento hidráulico de um perfil de solo não saturado de Aparecida de Goiânia-GO
(Universidade Federal de Goiás, 2010-04-30) BORGES, Camilla Rodrigues; VARGAS, Carlos Alberto Lauro; http://lattes.cnpq.br/3816106720170772; GITIRANA JUNIOR, Gilson de Farias Neves; http://lattes.cnpq.br/4710728908810849
The hydraulic behavior of a tropical and unsaturated soil profile of Aparecida de Goiânia-GO is presented. The main objective of this research was to contribute to the understanding of hydraulic properties of a tropical soil, with special emphasis on the soil-water characteristic curves and its hysteresis. The research work done was divided into two main parts: physical, chemical and mineralogical characterization; and hydraulic behavior for the unsaturated condition. The characterization tests indicate that the soil profile studied is formed by two horizons. The top layer of 1,50 m comprised of transported material and a bottom layer comprised of young residual soil. The results of particle size analysis have shown that the various sample preparation conditions (i.e., with or without drying, chemical and physical disaggregation) produce different grain-size distribution curves. A varying state of disaggregation can be achieved, that state being dependent on the stability of the soil aggregates. A fairly good correspondence between conventional hydrometer and laser diffraction analysis was achieved, considering supposedly equivalent aggregation conditions. The soil-water characteristic curve (SWCC) was measured for both the natural and the soil reconstituted by mud consolidation. The role played by the soil fabric on the hydraulic behavior of the soil was analyzed. The SWCC was obtained for drying, wetting, and mixed paths, both in terms of total and matric suction. It was determined that the natural and reconstituted soils have distinct SWCCs. The disaggregation achieved with the reconstituted soil results in higher air-entry values and a unimodal SWCC, even when the natural soil presents a bimodal SWCC. Therefore, the pore-size distribution if affected by the different soil structures. The procedure for wetting and drying soil samples used along with the filter paper technique resulted in a number of SWCCs showing absence of hysteresis. The study of the moisture content along the specimen s heights revealed non-homogeneous moisture content distributions, even after 14 day of equilibrium of water potential. It was concluded that it is the very existence of SWCC hysteresis, along with a not sufficiently slow wetting and drying from the specimen surface that results in a non-homogeneous moisture content.
Influência da chuva dirigida e dos detalhes arquitetônicos na durabilidade de revestimentos de fachada
(Universidade Federal de Goiás, 2010-05-21) MELO JÚNIOR, Carlos Mariano; CARASEK, Helena; http://lattes.cnpq.br/3023241186996790
The durability of the facades is related to performance against the deleterious effects of climatic elements, among them the wind driven rain, and the effects provided by the elements presents in building facades. Understanding these aspects is important for the prevention of pathological manifestations, increasing the capacity of the building to perform his functions for a long period. The presence of architectural and construction details can act as protective barriers or conductive elements of moisture from rain, well as a platform for deposition of pollutants and microorganisms, causing staining of the facades. Thus, this paper aims to point out the influences of wind driven rain and elements of facades of the durability of the facades of buildings located in Goiania-GO, related them to the cardinal points North, South, East and West. Methodologically, the paper seeks to: creation of the first maps of wind-driven rain to the city of Goiania, with data obtained from the National Institute of Meteorology in the period of 2002 to 2008; carrying out measurements of surfaces moisture on the four facades of the local building with mixed mortar rendering; data collection of cases of infiltration along the technical assistance for builders, relating them to their respective guidelines; identification of microorganisms collected on the façade elements and visual inspection with photographic record of the facades staining due to the inefficiency of the architectural and construction details. As main results, it was found that the infiltration and staining occur differently for each façade, due mainly, the specific climate of the city of Goiania. From the analysis of the results of the indices of wind driven rain, it was found that the facades oriented toward the North are more susceptible to moisture penetration by cracks and openings, fact also confirmed by the survey of cases of infiltration. For the identification of microorganisms, it was observed that facades face South tend to favor the growth of fungi, while the others showed the growth of phototrophs, justified by the increased incidence of the sunlight on these facades and the staining described generically as dirt due the pollutions are also the presence of microorganisms. From the standpoint of staining, observed an increased formation of spots near the region of window sill and dripping on the facades facing the South direction and greater presence of staining on the parapets of the facades facing the North directions. The fantômes occurred more frequently in walls of the South facades.
Estudo da formação da etringita tardia em concreto por calor de hidratação do cimento
(Universidade Federal de Goiás, 2010-07-05) Melo, Sandra Kurotusch de; Carasek, Helena; Hasparyk, Nicole Pagan; http://lattes.cnpq.br/4932240949129648; Hasparyk, . Nicole Pagan; Carasek , Helena; Araújo , Daniel de Lima; Dal Molin , Denise C. C. Dal Molin
Delayed ettringite formation (DEF) is a special type of an internal sulfate attack with SO42- ions from cement. This process is distinguished by neoformation of ettringite in concrete thermally cured at high temperature levels and exposed to high moisture in service life. This phenomenon can promote expansion and cracking, leading to rupture and spalling, achieving severe deterioration. This research had an experimental approach with the purpose to investigate DEF in concretes with pozzolanic Portland cement containing fly ash. These concretes were undergone to temperature rise by heat of hydration. It was produced two types of pumped concrete with cement content of 350 kg/m3 and 450 kg/m3 containing basaltic aggregate. Two big specimens were cast containing 200 liters of concrete and were immediately submitted to adiabatic temperature rise tests. After that, several specimens were drilled from them in order to evaluate compressive strength and elasticity modulus, as well as microstructural investigations by scanning electron microscopy (SEM) and X Ray diffraction (XRD) along 270 days. In addition, it was cast several cylindrical and prismatic samples with concrete containing 350 kg/m3of cement. Some of them were stored at the same condition of those during the thermal cure and others were conditioned in a moist room as reference, for properties and microstructural investigation. Prismatic ones were submitted to mass variation study, ultrasonic wave tests and also expansion tests. In order to complement this experimental program, a specific study on cement pastes was performed. This involved casting three series of cylindrical samples submitted to different cure cycles followed by evaluation of mass variation, ultrasonic velocity and also microstructure investigation by SEM and XRD. Main results proved that rising internal temperature of concrete by hydration heat above 60ºC promote delayed ettringite formation by microstructural analyses, although this formation had not caused negative consequences on mechanic properties of concretes up to age of 270 days evaluated. The study on the cement pastes confirmed that high temperatures affects the microstructure of cement matrix and also the formed products, collaborating to the formation of hydrated alumina phases besides ettringite. The presence of suggestive thaumasite at advanced ages seems to indicate that this calcium silicate sulfo-carbonate hydrate can accompany DEF process.
Análise do Desempenho de poços de infiltração na cidade de Goiânia-GO
(Universidade Federal de Goiás, 2010-07-31) ARAUJO, Alexandre Garces de; SALES, Maurício Martines; http://lattes.cnpq.br/2033708685029423; GITIRANA JUNIOR, Gilson de Farias Neves; http://lattes.cnpq.br/4710728908810849
This paper presents the performance study of infiltration pits. Two experimental fields were selected for evaluation of the pits, one studied by Carvalho (2008) and the other deployed in this work. The main objective of this research is to evaluate the sensitivity of the performance of the infiltration pit before the variability of soil properties. Three performance parameters were considered: time of infiltration 50%, 70% 85% the volume of water in the well. The variability of the properties was made with the use of possible values obtained by the coefficient of variation of each property evaluated. In the experimental field deployed in this study were collected undisturbed samples to perform laboratory tests such as characterization, consolidation test method, soil-water characteristic curve, saturated and unsaturated hydraulic conductivity. The SWCC showed the presence of macro structure and its format as bimodal. The saturated hydraulic conductivity showed that the soil behavior is governed by the macro structure, this resulted in hydraulic conductivity value close to the sandy. The hydraulic conductivity test was performed at the Federal University of Rio Grande do Sul using the permeameter developed by Feuerharmel (2007). The function of hydraulic conductivity obtained was compared with Brooks & Corey (1964) prediction method showing good results to the first baseline of SWCC. An automated method was developed for monitoring the variation of the water column in the well during infiltration. The method was based on the use of pressure sensors and a data acquisition system, comparing this method with using a conventional tape measure showed good results. Numerical analysis showed that the saturated hydraulic conductivity is the property that most influence on the performance of the structures of infiltration differences were not observed in the analysis considering different depth of groundwater level.
Análise dos fatores de interação entre estacas em radier estaqueado : comparação entre duas ferramentas numéricas
(Universidade Federal de Goiás, 2010-08-06) SOUZA, Ruiter da Silva; SALES, Maurício Martines; http://lattes.cnpq.br/2033708685029423
Researches done in the last decades concerning the settlement of pile foundations, mainly when it s considered as piled raft, had greatly evolved due the progress on computational tools used in the analysis. However, the tridimensional analysis of a pile foundation, taking into account the interaction between your components (soil, piles and raft), is still a very complex problem. To achieve a satisfactory evaluation of the interaction between the foundation's elements, numerical tools like Boundary Elements Method (B.E.M.), Finite Elements Method (F.E.M.) and hybrid methods, that combines two or more methods, are available, each one with its own advantages and drawbacks. The F.E.M. is considered in the technical sphere as the most complete method for piled raft evaluation, but your high processing time requirements, required in the analyses, prevents your usual employment. For this reason, a necessity to compare this methodology with others, as the one used in simplified programs, that decreases the processing time, arises. To evaluate the results proximity achieved by different methods, this work presents the simulation of some pile blocks, calculated as piled rafts, employing two programs (GARP and DIANA) to foresee your behavior. GARP is a hybrid program which analyzes the raft by using F.E.M. and the pilessoil set by B.E.M. and, like the other programs of same kind published in the literature, it doesn't take the influence between intermediary piles into account for the analysis. DIANA is a purely finite elements program, based on the displacement method. Thus, the main objective of this work was to evaluate how taking or not the interaction factor between piles into consideration can modify the predictions of settlement and pile loads. For that, it was evaluated how the attribution or omission of these interaction factors into specific regions that comprise some or all the piles, modifies the predictions of the foundation performance and makes them approximate or distant from the F.E.M. results, considering the most exact one. The way that the simplified programs handle the problem, makes the settlement previsions excessive. To contour this and to make the settlement results from the simplified methods become close of the expected ones from F.E.M., the discovered way was the imposition of a limit in the distance used in the calculation of the piles interaction, based on the raft's size and the number of piles in that case. Many examples of pile rafts in homogeneous soils was evaluated and the maximum distance limits of interaction between piles that generated the best results in the settlement prevision are shown. In all examples, the effect of raft stiffness in these results was also taken into account. Also, an analysis case in heterogeneous soil was done, where it was observed that this fact also interferes in the piles interaction process. For pile load predictions, the results were distinct from settlement prediction and was noticed that not limiting the maximum interaction distance between the piles generated the best previsions.
Construção e avaliação inicial de um trecho de pavimento asfáltico executado com misturas de solo tropical, fosfogesso e cal
(Universidade Federal de Goiás, 2010-08-13) METOGO, Daniel Arthur Nnang; REZENDE, Lilian Ribeiro de; http://lattes.cnpq.br/9258692609398794
Presently in Brazil, there is a real difficulty to reuse solid waste. Among them, the phosphogypsum, a byproduct of phosphatic acid production. The huge deposits of this waste become problematic both environmentally and economically. Therefore, researches are being conducted to find a reuse of this material in geotechnical engineering. In the specific case of its application in paving, beyond reuse waste, seek to reduce the exploitation of natural materials, traditionally used in construction of roads. Laboratory tests showed the possibility of use of phosphogypsum in paving when mixed with soil or chemically stabilizer. Thus, this study evaluates on field, the mechanical behavior of mixtures of phosphogypsum, tropical soil of Aparecida de Goiania-GO and lime, when used in base layers of asphalt pavement. For that, laboratory tests were performed to characterize the mixtures to be used on field and was constructed an experimental pavement with mixtures of soil (80%) + phosphogypsum (20%), soil (80%) + phosphogypsum (11%) + lime (9%), soil (91%) + lime (9%) and gravel (100%). During the experimental pavement construction, field tests specifics of paving were conducted, to check its good execution and evaluate its initial performance. To better understand the behavior of the experimental pavement, a second step of field tests was conducted, six months after the release of traffic. From this study, was been observed that both in laboratory and field, the mixture soil (80%) + phosphogypsum (11%) + lime (9%) was that which presented the best mechanical performances and can thus replace the gravel for construction of low cost pavement. However, care should be adopted to control the expansion of this mixture.

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