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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
61

Fracture testing and evaluation of asphalt pavement joints in quasi static tension mode

Ghafoori Roozbahany, Ehsan January 2012 (has links)
Asphalt joints are inevitable parts of every pavement. They are constructed for different reasons. Although much attention is dedicated to the construction joints (hot with hot pavement), a scientific approach for cold joints (cold with hot pavement) with respect to large patch constructions is still missing. This report tries to evaluate existing construction techniques and to suggest new testing methods of tests. Although, indirect tensile tests IDT and direct tension tests DTT are familiar in the field of asphalt pavement characterization, they have not been used for the assessment of joint quality so far. In this report, these two test types are evaluated and the results are analyzed using finite element software ABAQUS. The results of the comparison of joint compaction techniques on a laboratory scale suggest that joints with angles seem to show more promising behavior than vertical joints. Also, starting compaction from the hot side generally produces better results than compaction starting from cold side.
62

Cement Stabilization of Aggregate Base Materials Blended with Reclaimed Asphalt Pavement

Brown, Ashley Vannoy 12 May 2006 (has links) (PDF)
The purpose of this research was to investigate the effects of reclaimed asphalt pavement (RAP) content and cement content on the strength and durability of recycled aggregate base materials. Specifically, the unconfined compressive strength (UCS) and final dielectric value in the Tube Suction Test (TST) were measured in a full-factorial experimental design including five RAP contents, five cement contents, and three replicate specimens of each possible treatment. Specimen mixtures consisted of 0, 25, 50, 75, or 100 percent RAP and 0.0, 0.5, 1.0, 1.5, or 2.0 percent Type I/II Portland cement. Both the RAP and base materials were sampled from the I-84 pavement reconstruction project performed in Weber Canyon near Morgan, Utah, during the summers of 2004 and 2005. The laboratory testing procedures consisted of material characterizations, specimen preparation, and subjection of the specimens to strength and durability testing, and the data were evaluated using analysis of variance (ANOVA) testing. Both the RAP and base materials included in this research were determined to be non-plastic, and the AASHTO and Unified soil classifications for the RAP material were determined to be A-1-a and SM (well-graded sand with gravel), respectively, and for the base material they were A-1-a and SW-SM (well-graded sand with silt and gravel), respectively. The optimum moisture contents (OMCs) for the blended materials were between 5.6 and 6.6 percent, and maximum dry density (MDD) values were between 129.7 and 135.5 lb/ft3. In both cases, decreasing values were associated with increasing RAP contents. The results of the ANOVA performed on the UCS data indicate that UCS decreases from 425 to 208 psi as RAP content increases from 0 to 100 percent and increases from 63 to 564 psi as cement content increases from 0.0 to 2.0 percent. Similarly, the final dielectric value decreases from 14.9 to 6.1 as RAP content increases from 0 to 100 percent and decreases from 14.0 to 5.8 as cement content increases from 0.0 to 2.0 percent. With design criteria requiring 7-day UCS values between 300 and 400 psi and final dielectric values less than 10 in the TST, the results of this research suggest that milling plans should be utilized to achieve RAP contents in the range of 50 to 75 percent, and a cement content of 1.0 percent should be specified for this material. Cement contents less than 1.0 percent are not sufficient to stabilize the material, and greater cement contents may cause cracking. Because control of the actual cement content in the field depends on the contractor's equipment and skill, inspection protocols should be implemented during construction to ensure high-quality work. Additional recommendations are associated with the construction process. The specimens prepared in this research were compacted to relative densities of 100 percent using modified Proctor energy. Therefore, field compaction levels must approach these density values if the same material properties are to be achieved. In addition, all specimens tested in this study were cured at 100 percent relative humidity. Following compaction in the field, cement-treated layers should be moistened frequently during the first few days after construction or promptly sealed with a prime coat or wearing surface to ensure that the cement continues to hydrate. Variability in RAP and cement contents should also be minimized to achieve consistent material properties.
63

Evaluation of Full-depth Reclamation on Strength and Durability of Pavement Base Layers

Griggs, Benjamin Earl 24 March 2009 (has links) (PDF)
The purpose of this research was to determine the effect of full-depth reclamation (FDR) on the strength and durability of aggregate base layers in a coordinated approach involving both field and laboratory testing. Field comparisons between the pre-reclamation neat base and post-reclamation blended base were supplemented with laboratory experiments conducted to determine the effects of reclaimed asphalt pavement (RAP) content, compaction effort, and heating on the strength and durability of roadways reconstructed using FDR with a portable asphalt recycling machine (PARM). Also, the effect of reclamation on the spatial uniformity of the pavement structures was explored by comparing variability in the pre- and post-reclamation material properties. Test sites in Orem, Utah; San Marcos, Texas; and South Jordan, Utah, were selected for this research. The results of field testing indicate that the FDR process significantly increased the stiffness and/or strength of the base material at two of the test locations and did not significantly change the third base material. An evaluation of spatial variability indicated that the FDR process produced equivalent or lower spatial variability with respect to both base modulus and California bearing ratio (CBR) values at one site, while the other two sites exhibited equivalent or higher spatial variability after FDR. The results of laboratory testing for all three locations indicate that specimens compacted using the modified Proctor method exhibit significantly higher CBR values and dry densities than specimens compacted using the standard Proctor method. Also, the CBR values for specimens tested in the dry condition were significantly higher than those obtained from specimens tested at optimum moisture content. These results demonstrate the value of achieving a high level of compaction during construction and preventing water ingress into the pavement over time. The blended material exhibited a significantly lower CBR value than that of the neat material at only one location; the addition of RAP to materials at the other locations did not significantly change the CBR values of those materials. In the tube suction test (TST), most of the specimens were classified as marginally or highly moisture-susceptible, and the effect of RAP on the dielectric value in the TST was of no practical importance. The use of PARMs in the FDR process is an acceptable, economical, and environmentally friendly approach to reconstruction of flexible pavements. To ensure satisfactory performance of FDR projects, engineers and managers should carefully follow recommended guidelines for project selection, pavement testing, material characterization, design, construction, and quality assurance testing.
64

Effect of High Percentages of Reclaimed Asphalt Pavement on Mechanical Properties of Cement-Treated Base Material

Tolbert, Jacob Clark 10 July 2014 (has links) (PDF)
Full-depth reclamation (FDR) is an increasingly common technique that is used to rehabilitate flexible pavements. Implementation of FDR on rehabilitation projects produces several desirable benefits. However, these benefits are not fully realized due to the fact that state department of transportation specifications typically limit the reclaimed asphalt pavement (RAP) content of pavement base material to 50 percent. The objective of this research was to evaluate the effects of RAP content, cement content, temperature, curing time, curing condition, and moisture state on the strength, stiffness, and deformation characteristics of cement-treated base (CTB) mixtures containing high percentages of RAP.For this research, one aggregate base material and one RAP material were used for all samples. RAP content ranged from 0 to 100 percent in increments of 25 percent, and low, medium, and high cement levels corresponding to 7-day unconfined compressive strength (UCS) values of 200, 400, and 600 psi, respectively, were selected for testing. Moisture-density, UCS, resilient modulus, and permanent deformation tests were performed for various combinations of factors, and several statistical analyses were utilized to evaluate the results of the UCS, resilient modulus, and permanent deformation testing.The results of this work show that CTB containing RAP can be made to achieve 7-day UCS values approaching 600 psi regardless of RAP content. With regards to stiffness, the data collected in this study indicate that the resilient modulus of CTB containing RAP is affected by temperature in the range from 72 to 140°F for the low cement level. Permanent deformation of CTB containing RAP is significantly affected by RAP content and cement level at the test temperature of 140°F. At the low cement level, temperature is also a significant variable. As the 7-day UCS reaches approximately 400 psi, permanent deformation is reduced to negligible quantities. The results of this research indicate that the inverse relationship observed between permanent deformation and 7-day UCS is statistically significant.Given that the principle conclusion from this work is that CTB with high RAP contents can perform satisfactorily as a base material when a sufficient amount of cement is applied, agencies currently specifying limits on the percentage of RAP that can be used as a part of reclaimed base material in the FDR process should reevaluate their policies and specifications with the goal of allowing the use of high RAP contents where appropriate.
65

Modeling frost heave damages throughout the asphalt layer

Vosoughian, Saeed January 2022 (has links)
There are various distresses arising from traffic loads and the surrounding environment to whichan asphalt pavement is subjected during its life span. The environment-associated damages aremore severe during winter when abundant moisture and freezing temperature are presentsimultaneously. Damage caused by frost heave is one of the important winter-related damagesresulting in severe cracks and bumpy road surfaces. Since the frost heave-induced cracks areusually wide, they can make the pavement more prone to other types of damage by leaving theopen space for water and moisture penetration. Simulating the response of the pavement whenit is subjected to frost heave is the aim of this licentiate thesis. Attaining this objective requirescoupling a frost heave model with a damage model representing the mechanistic behavior ofthe asphalt material. With regard to the brittle behavior of the asphalt at cold temperatures, aviscoelastic damage model for asphalt material is coupled with a thermomechanical frost heavemodel. The thermomechanical approach couples the physical processes involved in frost actioninside the soil. To elucidate more, in this method the thermal and mechanical fields are coupledby the porosity evolution function which implicitly takes into account the effect of the hydraulicfield. On the other hand, the continuum viscoelastic damage model for asphalt material isdeveloped within the infinitesimal strain context by applying the thermodynamical restrictionsof irreversible processes. The suggested framework was employed in different finite elementmodels to simulate damages caused by frost heave in asphalt pavements. The results indicatethat it predicts the damage distribution and evolution in the asphalt. Furthermore, it was shownthat the uneven frost heave and physical processes taking place in the soil during frost actionsuch as cryogenic suction force creation, porosity evolution, ice formation, etc., can also besimulated. / Det finns olika typer av påfrestningar som uppstår från trafikbelastningar och den omgivandemiljön som en asfaltbeläggning utsätts för under sin livslängd. De miljörelaterade skadorna ärallvarligare under vintern när fukt och kalla temperaturer är närvarande samtidigt. Skadororsakade av tjällyft är en av de allvarliga vinterrelaterade skadorna som resulterar i sprickor ochskadade vägsytor. Eftersom de tjällyftsinducerade sprickorna vanligtvis är breda kan de görabeläggningen mer utsatt för andra typer av skador genom vatten- och fuktinträngning. Syftetmed denna licentiatavhandling är att simulera beläggningens reaktion när den utsätts för tjällyft.För att uppnå detta mål krävs att en tjällyftsmodell kopplas till en skademodell somrepresenterar asfaltmaterialets mekanistiska beteende. När det gäller asfaltens spröda beteendevid kalla temperaturer, är en viskoelastisk skademodell för asfaltmaterial kopplad till entermomekanisk tjällyftsmodell. Det termomekaniska tillvägagångssättet kopplar de fysiskaprocesserna som är involverade i frostverkan inuti jorden. För att klarlägga detta mer, är determiska och mekaniska fälten kopplade med porositetsutvecklingsfunktionen som implicit tarhänsyn till effekten av det hydrauliska fältet. Å andra sidan är den kontinuumviskoelastiskaskademodellen för asfaltmaterial utvecklad inom det oändliga töjningssammanhanget genomatt tillämpa de termodynamiska begränsningarna av irreversibla processer. Det föreslagnaramverket användes i olika finita elementmodeller för att simulera skador orsakade av tjällyft iasfaltbeläggningar. Resultaten indikerar att den förutsäger skadefördelningen och utvecklingeni asfalten. Dessutom har det visat sig att det ojämna tjällyft och fysiska processer som äger rumi marken under frostpåverkan, såsom skapande av kryogen sugkraft, porositetsutveckling,isbildning, etc., också kan simuleras. / <p>QC 20221124</p>
66

Viscoelastic FE Modeling of Asphalt Pavements and Its Application to U.S. 30 Perpetual Pavement

Liao, Yun January 2007 (has links)
No description available.
67

Rapid estimation of lives of deficient superpave mixes and laboratory-based accelerated mix testing models

Manandhar, Chandra Bahadur January 1900 (has links)
Doctor of Philosophy / Department of Civil Engineering / Mustaque Hossain / The engineers from the Kansas Department of Transportation (KDOT) often have to decide whether or not to accept non-conforming Superpave mixtures during construction. The first part of this study focused on estimating lives of deficient Superpave pavements incorporating nonconforming Superpave mixtures. These criteria were based on the Hamburg Wheel-Tracking Device (HWTD) test results and analysis. The second part of this study focused on developing accelerated mix testing models to considerably reduce test duration. To accomplish the first objective, nine fine-graded Superpave mixes of 12.5-mm nominal maximum aggregate size (NMAS) with asphalt grade PG 64-22 from six administrative districts of KDOT were selected. Specimens were prepared at three different target air void levels @ N[subscript]design gyrations and four target simulated in-place density levels with the Superpave gyratory compactor. Average number of wheel passes to 20-mm rut depth, creep slope, stripping slope, and stripping inflection point in HWTD tests were recorded and then used in the statistical analysis. Results showed that, in general, higher simulated in-place density up to a certain limit of 91% to 93%, results in a higher number of wheel passes until 20-mm rut depth in HWTD tests. A Superpave mixture with very low air voids @ N[subscript]design (2%) level performed very poorly in the HWTD test. HWTD tests were also performed on six 12.5-mm NMAS mixtures with air voids @ N[subscript]design of 4% for six projects, simulated in-place density of 93%, two temperature levels and five load levels with binder grades of PG 64-22, PG 64-28, and PG 70-22. Field cores of 150-mm in diameter from three projects in three KDOT districts with 12.5-mm NMAS and asphalt grade of PG 64-22 were also obtained and tested in HWTD for model evaluation. HWTD test results indicated as expected. Statistical analysis was performed and accelerated mix testing models were developed to determine the effect of increased temperature and load on the duration of the HWTD test. Good consistency between predicted and observed test results was obtained when higher temperature and standard load level were used. Test duration of the HWTD can thus be reduced to two hours or less using accelerated mix testing (statistical) models.
68

Hydraulic conductivity measurement of permeable friction course (PFC) experiencing two-dimensional nonlinear flow effects

Klenzendorf, Joshua Brandon 04 October 2010 (has links)
Permeable Friction Course (PFC) is a layer of porous asphalt pavement with a thickness of up to 50 millimeters overlain on a conventional impervious hot mix asphalt or Portland cement concrete roadway surface. PFC is used for its driver safety and improved stormwater quality benefits associated with its ability to drain rainfall runoff from the roadway surface. PFC has recently been approved as a stormwater best management practice in the State of Texas. The drainage properties of PFC are typically considered to be governed primarily by two hydraulic properties: porosity and hydraulic conductivity. Both of these hydraulic properties are expected to change over the life of the PFC layer due to clogging of the pore space by trapped sediment. Therefore, proper measurement of the hydraulic properties can be problematic. Laboratory and field tests are necessary for accurately determining the hydraulic conductivity of the PFC layer in order to ensure whether the driver safety and water quality benefits will persist in the future. During testing, PFC experiences a nonlinear flow relationship which can be modeled using the Forchheimer equation. Due to the two-dimensional flow patterns created during testing, the hydraulic conductivity cannot be directly measured. Therefore, numerical modeling of the two-dimensional nonlinear flow relationship is required to convert the measureable flow characteristics into the theoretical flow characteristics in order to properly determine the isotropic hydraulic conductivity. This numerical model utilizes a new scalar quantity, defined as the hydraulic conductivity ratio, to allow for proper modeling of nonlinear flow in two-dimensional cylindrical coordinates. PFC core specimens have been extracted from three different roadway locations around Austin, Texas for the past four years (2007 to 2010). Porosity values of the core specimens range from 12% to 23%, and the porosity data suggest a statistical decrease over time due to trapped sediment in the pore space. A series of constant head tests used in the laboratory and a falling head test used in the field are recommended for measurement of PFC hydraulic characteristics using a modified Forchheimer equation. Through numerical modeling, regressions equations are presented to estimate the hydraulic conductivity and nonlinear Forchheimer coefficient from the measureable hydraulic characteristics determined during experimental testing. Hydraulic conductivity values determined for laboratory core specimens range from 0.02 centimeters per second (cm/s) to nearly 3 cm/s. Field measurements of in-situ hydraulic conductivity vary over a range from 0.6 cm/s to 3.6 cm/s. The results of this research provide well-defined laboratory and field methods for measurement of the isotropic hydraulic conductivity of PFC experiencing two-dimensional nonlinear flow and characterized by the Forchheimer equation. This methodology utilizes a numerical model which presents a proper solution for nonlinear flow in two-dimensions. / text
69

Critérios para avaliação pericial da macro e microtextura de pavimento asfáltico em local de acidente de trânsito / Criteria for the expert evaluation of macro and micro texture of the asphalt pavement at traffic accident sites

Bucharles, Luciano Gardano Elias 28 March 2014 (has links)
Muito embora a micro e a macrotextura dos pavimentos sejam importantes para o tráfego seguro, principalmente em condição de pista molhada e com velocidades superiores a 50 km/h, nos locais de acidentes de trânsito no Brasil esses parâmetros não são avaliados quando das perícias técnicas. Assim, o objetivo principal desta tese é estabelecer critérios de avaliação de pavimentos asfálticos que possam integrar um protocolo para a perícia técnica em locais de acidentes de trânsito. Foi baseada em coleta de dados de micro e de macrotextura dos revestimentos asfálticos em três rodovias no Estado do Paraná, num total de 106 locais, e em quatro vias urbanas na cidade de Londrina-PR, num total de 148 locais, todas com velocidades permitidas iguais ou superiores a 50 km/h, especificamente em trechos onde ocorreram acidentes de trânsito, o que permitiu a determinação da aderência na interface pneu/pavimento, se os valores encontram-se dentro das faixas de aceitabilidade do DNIT, da ANTT e da ARTESP e se houve efetiva contribuição do pavimento para a ocorrência e para a severidade dos acidentes. Dos 106 acidentes rodoviários analisados, em 19 deles as alturas médias de mancha de areia, parâmetro empregado para avaliar a macrotextura, apresentaram-se com valor inferior ao mínimo recomendado (0,60 mm), enquanto que dos 148 acidentes ocorridos em vias urbanas, 22 ocorreram em trechos com alturas médias de mancha de areia também inferiores ao valor mínimo recomendado. Nesses casos também foram realizados ensaios de microtextura, com uso do pêndulo britânico, e posteriormente foram calculados os valores do Índice de Atrito Pneu-Pavimento Internacional (International Friction Index, IFI). Os resultados e as análises deste trabalho indicam que uma melhor condição de macrotextura pode reduzir entre 6% e 19% as energias cinéticas envolvidas nos acidentes em rodovias e de 3% a 11% em vias urbanas, com real possibilidade de redução tanto das avarias produzidas nos veículos quanto, principalmente, das lesões nas vítimas. Dada a importância da micro e da macrotextura, recomenda-se que o protocolo de avaliação de pavimentos para perícias técnicas em locais de acidentes de trânsito em rodovias e em vias urbanas estabeleça a realização dos ensaios de Pêndulo Britânico e de Mancha de Areia em até 24 horas após o evento e que a área a ser levantada contemple toda a extensão das marcas de frenagem dos veículos envolvidos ou, no caso de inexistência de marcas, que compreenda uma extensão de 10 a 70 metros, respectivamente para vias com velocidade máxima permitida de 40 km/h e de 120 km/h. Espera-se, complementarmente, que um protocolo com critérios simples e objetivos, como o desenvolvido neste trabalho, permita a adoção de políticas públicas preventivas, de maior alcance e periodicidade, com as avaliações não somente nos trechos onde ocorrem acidentes, mas ao longo das vias. / Although the micro and macro textures of pavements are important factors for safe driving, especially on wet tracks and with speeds above 50 km/h, such parameters are not even evaluated during technical inspections in traffic accident sites in Brazil. Thus, the main purpose of this thesis is to establish criteria for the evaluation of asphalt pavements that may become integral part of a protocol for technical inspection in traffic accident sites. This work is based on the collection of data concerning the micro and macro texture of asphalt pavements on three roads in the State of Paraná, totaling 106 locations, and on four urban streets in the city of Londrina, State of Paraná, totaling 148 locations. All such locations have a speed limit of equal to or higher than 50 km/h, especially on the sites where traffic accidents occurred, which allowed for the determination of the tire/pavement adherence, and whether the values found were in accordance with the acceptable levels established by DNIT, ANTT and ARTESP, and whether there was effective contribution on the part of the pavement for the occurrence as well as the severity of the accidents. Out of the 106 road accidents that were analyzed, it was observed that in 19 of them the average heights of the sand spot, a parameter used to evaluate the macro-texture, were lower than the minimum value recommended (0,60 mm), while out of the 148 accidents taken place in urban streets, 22 took place in areas where the average heights of the sand spot were also lower than the recommended minimum value. In the case of the accidents that occurred in places where the heights of the sand spots were lower than the minimum recommended, micro texture essays were also carried out by use of the British Pendulum Tester, and later the values of the International Friction Index (IFI) were calculated. The results and the analyzes of this work indicated that a better condition in the macro texture would reduce the kinetic energies involved in road accidents between 6% and 19%, and from 3% to 11% on urban streets, with the real possibility of minimizing both damages caused to the vehicles and especially the lesions on the victims. Given the importance of micro and macro textures, it is recommended that the protocol for the evaluation of pavements for the purpose of technical inspection in traffic accident sites both on roads and urban streets require the carrying out of the British Pendulum Tester and the Sand Spot within 24 hours of the time of the accident and that the area to be tested should include the entire extension of the braking skid marks of the vehicles involved in the accident, or, in the case of inexistence of such marks, covering 10 to 70 meters, respectively, for locations where the permitted maximum speed is 40 km/h, and for locations where the permitted maximum speed is 120 km/h. It is additionally expected that a protocol having simple yet objective criteria, such as the ones developed in this work, will allow for the adoption of preventive public policies, having greater scope and periodical applications, not only on sites where accidents take place, but also on the entirety of roads and streets.
70

Estudo laboratorial de bases granulares recicladas in situ / Laboratory study of recycled granular bases in situ

Silva Junior, Valdemar Martins da 24 March 2015 (has links)
Submitted by Marlene Santos (marlene.bc.ufg@gmail.com) on 2016-03-02T20:13:41Z No. of bitstreams: 2 Dissertação - Valdemar Martins da Silva Junior- 2015.pdf: 3819482 bytes, checksum: 97968b41a20cc121c38122d649390f5b (MD5) license_rdf: 19874 bytes, checksum: 38cb62ef53e6f513db2fb7e337df6485 (MD5) / Approved for entry into archive by Luciana Ferreira (lucgeral@gmail.com) on 2016-03-03T12:18:00Z (GMT) No. of bitstreams: 2 Dissertação - Valdemar Martins da Silva Junior- 2015.pdf: 3819482 bytes, checksum: 97968b41a20cc121c38122d649390f5b (MD5) license_rdf: 19874 bytes, checksum: 38cb62ef53e6f513db2fb7e337df6485 (MD5) / Made available in DSpace on 2016-03-03T12:18:00Z (GMT). No. of bitstreams: 2 Dissertação - Valdemar Martins da Silva Junior- 2015.pdf: 3819482 bytes, checksum: 97968b41a20cc121c38122d649390f5b (MD5) license_rdf: 19874 bytes, checksum: 38cb62ef53e6f513db2fb7e337df6485 (MD5) Previous issue date: 2015-03-24 / Fundação de Apoio à Pesquisa - FUNAPE / The full depth reclamation technique of pavements consists in the reuse of granular materials of existing layers as well as the granular and bituminous materials that compose the deteriorated asphalt layer may also add aggregates or chemical stabilizers, giving rise to a new base that will receive a new asphalt layer. Besides eliminating the need of spoil area of material from asphalt layer deteriorated, this technique gives greater agility to the site and a reduction in costs. This research was motivated by the agreement between the university (Universidade Federal de Goiás) and the government inspection agency (Controladoria Geral do Estado de Goiás – CGE-GO) and its main objective to evaluate laboratory if the solutions specified in the project are technically suitable for the pavements offer a satisfactory performance. The research has the specific objectives: to determine if the amount of gravel added to recycling is the amount specified in the project and, if indeed, this percentage is the one submitting the best mechanical results and check whether there was or not the breaking of aggregates during the compaction. Initially, a deformed sample of recycling material of four roads were collected in the field and from the accomplishment of conventional laboratory tests (characterization, compaction, expansion and California Bearing Ratio) and dynamic triaxial tests their characteristics and properties were determined and analyzed. Furthermore, a dosage study related to the amount of gravel added to the mixture was also carried out to check which content would provide a better performance to the pavement. The stress analysis was performed using the computer program Sigma / W and from the stresses acting in the bases of the roads was obtained the resilient modulus values of each base material used in the reconstructions and the results were compared with values obtained in existing similar studies. Among the base materials used in the reconstructions of the four roads studied, three showed resilient modulus in the laboratory higher to 400 MPa. From the analysis of the results, it appears that the recycled base with the addition of gravel has potential of application in the region of study. However, to be successful in the practice and the best relation for money, it is important to make a preliminary study of dosage, set the adequate compaction power, perform executive control on the site and evaluate the technical basis of specifications which they consider mechanistic parameters, still little existing in Brazil. / A técnica de reciclagem profunda de pavimentos consiste na reutilização dos materiais granulares das camadas existentes, bem como dos materiais granulares e betuminosos que compõem o revestimento deteriorado, podendo ainda adicionar agregados ou estabilizantes químicos, dando origem a uma nova base que irá receber um novo revestimento asfáltico. Além de eliminar a necessidade de áreas destinadas ao bota fora do material proveniente do revestimento asfáltico deteriorado, essa técnica confere maior agilidade à obra e uma redução nos custos. A realização desta pesquisa foi motivada pelo convênio firmado entre a Universidade Federal de Goiás (UFG) e a Controladoria Geral do Estado de Goiás (CGE-GO) e tem como objetivo principal avaliar laboratorialmente se as soluções especificadas em projeto são adequadas tecnicamente para o pavimento oferecer um desempenho satisfatório. A pesquisa tem como objetivos específicos: verificar se a quantidade de brita adicionada à reciclagem é a especificada em projeto e, se de fato, esse percentual é o que apresenta o melhor resultado mecânico e verificar se houve ou não a quebra de agregados durante o processo de compactação. Inicialmente, foram coletadas em campo amostras deformadas do material proveniente da reciclagem do pavimento de quatro rodovias e a partir da realização de ensaios laboratoriais convencionais (caracterização, compactação, expansão e California Bearing Ratio) e de ensaios triaxiais dinâmicos suas características e propriedades foram determinadas e analisadas. Além disso, um estudo de dosagem referente à quantidade de brita adicionada à mistura também foi realizado para verificar qual teor proporcionaria um melhor desempenho ao pavimento. A análise de tensões foi realizada através do programa computacional Sigma/W e a partir das tensões atuantes nas bases das rodovias obteve-se os valores de módulo resiliente de cada material de base utilizado nas reconstruções e os resultados encontrados foram comparados com valores obtidos em estudos similares existentes. Dentre os materiais de base utilizados nas reconstruções das quatro rodovias estudadas, três apresentaram módulo resiliente em laboratório superior a 400 MPa. A partir da análise dos resultados, verifica-se que a base reciclada com adição de brita tem potencial de aplicação na região de estudo. No entanto, para ter sucesso no emprego da prática e a melhor relação custo benefício, é importante realizar estudo preliminar de dosagem, definir a energia de compactação adequada, realizar controle executivo na obra e avaliar a técnica com base em especificações que considerem parâmetros mecanísticos, ainda pouco existentes no Brasil.

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