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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.
11

Verification of Mechanistic-Empirical Pavement Deterioration Models Based on Field Evaluation of In-Service Pavements

Gramajo, Carlos Rafael 15 July 2005 (has links)
This thesis focused on using a detailed structural evaluation of seven (three flexible and four composite) high performance in-service pavements designated as high-priority routes to verify the applicability of the Mechanistic Empirical (M-E) models to high performance pavements in the Commonwealth of Virginia. The structural evaluation included: determination of layer thicknesses (from cores, GPR and historical data), pavement condition assessment based on visual survey, estimation of layer moduli from FWD analysis as well as material characterization. One of the main objectives of this study was to utilize the results from the backcalculated moduli in order to predict the performance of this group of pavement structures using the M-E Design Guide Software. This allowed a quick verification of the performance prediction models used by comparing their outcome with the current condition. The in-depth structural evaluation of the three flexible and four composite pavements showed that all the sites are structurally sound. The investigation also confirmed that the use of GPR to determine layer thicknesses and the comparison with a minimum number of cores is a helpful tool for pavement structural evaluation. Despite some difficulties performing the backcalculation analysis for complex structures, the obtained results were considered reasonable and were useful in estimating the current structural adequacy of the evaluated structures. The comparison of the measured distresses with those predicted by the M-E Design Guide software showed poor agreement. In general, the predicted distresses were higher than the distresses actually measured. However, there was not enough evidence to determine whether this is due to errors in the prediction models or software, or because of the use of defaults material properties, specially for the AC layers. It must be noted that although an in-depth field evaluation was performed, only Level 3 data was available for many of the input parameters. The results suggest that significant calibration and validation will be required before implementation of the M-E Design Guide. / Master of Science
12

Evaluation of low-quality recycled concrete pavement aggregates for subgrade soil stabilization

Tavakol, Masoumeh January 1900 (has links)
Doctor of Philosophy / Department of Civil Engineering / Mustaque A. Hossain / Stacey E. Kulesza / Recycled concrete aggregate (RCA) is the byproduct of the demolition of concrete structures and pavements. An estimated 140 million tons of concrete waste is produced annually in the United States, most of which ends up in landfills. The use of RCA to replace quarried aggregates in paving projects is one way to utilize these materials and alleviate concerns regarding this increasing waste stream. RCA usage prevents waste concrete disposal into landfills, resulting in more sustainable use of mineral aggregate sources, and may further reduce costs associated with paving projects. However, the inferior physical properties of RCA, such as the presence of recycled mortar, complicate the incorporation of RCA into new concrete mixtures. State highway agencies such as the Kansas Department of Transportation are facing further issues with RCA from D-cracked pavements, raising the question if D-cracked aggregates should be used in paving operations. No known work has evaluated the effect of RCA from D-cracked pavements in subgrade soil stabilization. This study stabilized a low-plasticity clay in Kansas using RCA and three stabilizing materials (lime, Class C fly ash, and a combination of Portland cement and fly ash). Candidate mixtures with varying proportions of chemical stabilizers and D-cracked aggregates were evaluated using the standard Proctor, unconfined compressive strength, linear shrinkage, and California Bearing Ratio tests. Microstructure characteristics of selected mixtures were explored using scanning electron microscopy (SEM) and energy dispersive X-ray tests. Laboratory test results indicated that RCA, in conjunction with all cementitious materials except lime, improved clay strength, stiffness, and shrinkage properties. SEM results indicated that RCA caused a low void space and a dense arrangement of soil particles. RCA effectively improved evaluated mixture properties when an adequate soil-RCA bond was reached using chemical agents. The long-term performance of full-depth flexible pavements with stabilized mixtures as subgrade was assessed in the AASHTOWare Pavement ME Design (commonly known as MEPDG) software. The life-cycle cost of flexible pavements with stabilized mixtures was estimated for a 40-year design period. Economic analysis results indicated that RCA was cost effective only if it was used with a combination of fly ash and Portland cement.
13

Efeitos da composição de resíduos de construção e demolição em seu comportamento mecânico para utilização em pavimentação / The effects of composition of construction and demolition waste on their mechanical behavior for use in paving

Matuella, Matheus Ferreira January 2017 (has links)
A indústria da construção civil utiliza grandes volumes de recursos naturais e, concomitantemente, produz elevadas quantidades de resíduos de construção e demolição (RCD), que são pouco reaproveitados e, às vezes, descartados de forma inadequada. Por reduzir a quantidade de matérias-primas extraídas da natureza, a construção de pavimentos aparece como destino nobre para os RCD. Contudo como esses materiais podem apresentar elevada heterogeneidade em sua composição, questiona-se se isso pode influenciar seu comportamento mecânico. A pesquisa relatada nesta dissertação buscou analisar as características físicas e comportamento mecânico de RCD de concreto (RCD cinza), e desse material misturado com RCD cerâmico (RCD vermelho). Acrescentando-se de 0 a 50% de tijolos maciços britados aos resíduos de concreto, reproduziram-se composições encontradas em obras civis. A partir de resultados de ensaios de granulometria, compactação, abrasão, compressão triaxial e módulo de resiliência (MR), compararam-se os comportamentos das mesmas. Com auxílio do software Everstress 5.0, foram feitas análises mecanísticas de pavimentos com bases compostas desses materiais, de forma que fossem estimados seus desempenhos frente a diferentes mecanismos de degradação. Observou -se que o aumento na porcentagem de RCD cerâmico afeta significativamente o comportamento mecânico do RCD misto, aumentando a perda de massa por abrasão e o teor de umidade ótimo de compactação, reduzindo o peso específico aparente seco máximo, a coesão e o módulo de resiliência e tornando o material menos dependente do estado de tensões. Conclui-se que a composição de resíduos de construção e demolição afeta seu comportamento mecânico e tem influência significativa no desempenho de pavimentos em que forem usados. Verifica-se que tanto os RCD cinza, quanto os mistos podem suportar as solicitações do tráfego, fortalecendo-se a filosofia de aliar a construção de pavimentos aptos estruturalmente a um modo de construir que contribua para a redução da exploração e degradação do meio ambiente. / The construction industry uses large volumes of natural resources and, at the same time, produces a high amount of construction and demolition waste (CDW), which are little reused and sometimes discarded inappropriately. In order to reduce the amount of raw materials extracted from nature, the construction of pavements appears as a noble destination for the use of CDW. However, since these materials may present high heterogeneity in their composition, it is questioned whether this may influence their mechanical behavior. The research reported in this dissertation aimed at analyzing the physical characteristics and mechanical behavior of recycled concrete aggregate (RCA) and this material mixed with crushed bricks. Adding from 0 to 50% of ceramic CDW to concrete residues, compositions found in civil works were reproduced. From the results of grain size distribution, abrasion, triaxial compression and resilience modulus tests, their behavior was compared. Using Everstress 5.0 software, mechanistic analysis of pavements with bases made of these materials were performed, so that their performances against different degradation mechanisms were estimated. It was observed that the increase in the percentage of ceramic CDW influences the behavior of the mixed CDW, increasing the abrasion mass loss and the optimum compaction moisture content, reducing the apparent maximum dry unit weight, cohesion and the modulus of resilience and making the material less dependent on the stress state. It is concluded that the composition of construction and demolition waste directly influences its mechanical behavior and has a significant influence on the performance of pavements in which they are used. Both RCA and mixed CDW have the potential to withstand traffic loads, strengthening the philosophy of combining the construction of pavements structurally capable with a construction mode that contributes to the reduction of exploration and degradation of the environment.
14

Quick Shear Testing of Aggregate Base Materials Stabilized with Geogrid

Selk, Rawley Jack 01 July 2017 (has links)
The objective of this research was to apply a previously recommended laboratory testing protocol to specific aggregate base materials that are also the subject of ongoing full-scale field testing. The scope of this research involved three aggregate base materials selected from three sites where full-scale field testing programs have been established. The first and second field sites included five different geogrid types, categorized as either biaxial or triaxial, in a singlelayer configuration, while the third site included only the triaxial geogrid type in either a singleor double-layer configuration. Geogrid-stabilized and unstabilized control specimens were evaluated using the American Association of State Highway and Transportation Officials T 307 quick shear testing protocol. Measurements of load and axial displacement were recorded and used to develop a stress-strain plot for each specimen tested. The peak axial stress, the modulus to the peak axial stress, the modulus of the elastic portion of the curve, and the modulus at 2 percent strain were then calculated. Statistical analyses were performed to investigate differences between geogridstabilized specimens and unstabilized control specimens and to investigate differences between individual geogrid products or geogrid configurations. Depending on the method of data analysis, the quick shear test results indicate that geogrid stabilization, with the effect of geogrid stabilization averaged across all of the geogrid products evaluated in this study, may or may not improve the structural quality of the aggregate base materials evaluated in this study. The results also indicate that, regardless of the method of analysis, one geogrid product or configuration may be more effective than another at improving the structural quality of a given aggregate base material as measured using the quick shear test. All results from this research are limited in their application to the aggregate base material types, geogrid products, and geogrid configurations associated with this study. Additional research is needed to compare the results of the laboratory quick shear testing obtained for this study with the structural capacity of the geogrid-stabilized and unstabilized control sections that have been constructed at corresponding full-scale field testing sites. Specifically, further research is needed to determine which method of laboratory data analysis yields the best comparisons with field test results. Finally, correlations between the results of quick shear testing and resilient modulus need to be investigated in order to incorporate the findings of the quick shear test on geogrid-stabilized base materials into mechanistic-empirical pavement design.
15

Development of reliable pavement models

Aguiar Moya, José Pablo, 1981- 13 October 2011 (has links)
As the cost of designing and building new highway pavements increases and the number of new construction and major rehabilitation projects decreases, the importance of ensuring that a given pavement design performs as expected in the field becomes vital. To address this issue in other fields of civil engineering, reliability analysis has been used extensively. However, in the case of pavement structural design, the reliability component is usually neglected or overly simplified. To address this need, the current dissertation proposes a framework for estimating the reliability of a given pavement structure regardless of the pavement design or analysis procedure that is being used. As part of the dissertation, the framework is applied with the Mechanistic-Empirical Pavement Design Guide (MEPDG) and failure is considered as a function of rutting of the hot-mix asphalt (HMA) layer. The proposed methodology consists of fitting a response surface, in place of the time-demanding implicit limit state functions used within the MEPDG, in combination with an analytical approach to estimating reliability using second moment techniques: First-Order and Second-Order Reliability Methods (FORM and SORM) and simulation techniques: Monte Carlo and Latin Hypercube Simulation. In order to demonstrate the methodology, a three-layered pavement structure is selected consisting of a hot-mix asphalt (HMA) surface, a base layer, and subgrade. Several pavement design variables are treated as random; these include HMA and base layer thicknesses, base and subgrade modulus, and HMA layer binder and air void content. Information on the variability and correlation between these variables are obtained from the Long-Term Pavement Performance (LTPP) program, and likely distributions, coefficients of variation, and correlation between the variables are estimated. Additionally, several scenarios are defined to account for climatic differences (cool, warm, and hot climatic regions), truck traffic distributions (mostly consisting of single unit trucks versus mostly consisting of single trailer trucks), and the thickness of the HMA layer (thick versus thin). First and second order polynomial HMA rutting failure response surfaces with interaction terms are fit by running the MEPDG under a full factorial experimental design consisting of 3 levels of the aforementioned design variables. These response surfaces are then used to analyze the reliability of the given pavement structures under the different scenarios. Additionally, in order to check for the accuracy of the proposed framework, direct simulation using the MEPDG was performed for the different scenarios. Very small differences were found between the estimates based on response surfaces and direct simulation using the MEPDG, confirming the accurateness of the proposed procedure. Finally, sensitivity analysis on the number of MEPDG runs required to fit the response surfaces was performed and it was identified that reducing the experimental design by one level still results in response surfaces that properly fit the MEPDG, ensuring the applicability of the method for practical applications. / text
16

Análise estrutural de pavimentos de baixo volume de tráfego revestidos com solo modificado com cal considerando ensaios laboratoriais e monitoramento de trechos experimentais / Structural Analyze of low-volume roads covered with soil modified with lime with considering of laboratorial tests and monitoring of experimental sections

Katz, Leonardo Behak January 2013 (has links)
Os solos das regiões arrozeiras apresentam características geotécnicas inadequadas para uso como revestimentos primários de estradas. Isto força o transporte de materiais de jazidas distantes, o que, além de onerar o custo de construção, nem sempre é uma solução durável. Nesta tese relata-se uma pesquisa que apresenta uma solução para esse problema: a pavimentação de estradas de baixo volume de tráfego com solo local modificado com cal. Foram realizados estudos laboratoriais e de campo, e os resultados analisados através de uma abordagem mecanístico-empírica. Dois pavimentos experimentais com revestimentos de solo-cal foram construídos e monitorados próximo a Cebollatí, leste do Uruguai. Foram realizados ensaios de caracterização e comportamento mecânico do solo e de misturas de solo e cal, variando-se o teor de cal, o tempo de cura e a energia de compactação. Realizaram-se ensaios de módulo de resiliência, para o qual foi projetado, montado e operado o primeiro equipamento de ensaios de carga repetida na compressão triaxial do Uruguai. Também foram realizados ensaios de fadiga na compressão diametral para o solo modificado com 3% e 5% de cal, curado por 28 e 150 dias. Para entender o comportamento das camadas de solo modificado com cal submetidas ao tráfego, realizou-se uma análise conjunta dos resultados laboratoriais e do monitoramento dos trechos experimentais, com uso de modelos computacionais. Apesar das limitações construtivas, de terem sido liberados ao tráfego em plena safra e das más condições de drenagem da região, após 5 anos de trafego, os pavimentos não mostram trincas de fadiga ou afundamentos nas trilhas de roda. Assim, a pavimentação de estradas de baixo volume de tráfego em regiões arrozeiras com revestimentos de solo local modificado com cal provou ser uma alternativa economicamente vantajosa, por reduzir custos de construção e manutenção, e sustentável, por preservar materiais não-renováveis, como solos e rochas. / Soils in rice plantation areas generally present geotechnical characteristics unsuitable for use as primary wearing course of roads. Because of that, it is necessary to import materials from distant sites, a solution that, besides increasing construction cost, is rarely long-lasting. In this thesis a research on paving low volume roads with lime modified local soils is reported, in order to present an alternative solution to that problem. Both laboratory and field studies were carried out and the results were analyzed by means of a mechanistic-empirical approach. Two test sections with wearing courses made of lime modified soil were built and monitored close to Cebollatí, a village in the east of Uruguay. Previously, laboratory characterization and mechanical tests on samples of the sedimentary soil were carried out. Lime contents for mixtures were determined and the stress-strain-strength behavior of mixes with different levels of lime content, curing time and compaction energy was studied. In order to analyze the elastic behavior of the lime modified soil under traffic, resilient modulus tests were carried out. This motivated the design, assembly and use of the first equipment for triaxial compression repeated loading tests in Uruguay. Besides, stress controlled fatigue tests were performed on cylindrical specimens of soil modified with 3% and 5% of lime, cured for 28 and 150 days. The results of laboratory tests and field monitoring were analyzed using computational models. In spite of the difficulties faced during pavements construction, including heavy traffic in early days, and the poor drainage, after 5 years of service no cracks or ruts are seen on top of the test pavements. Therefore, paving low volume roads in rice plantation areas with lime modified wearing courses has proved to be a cost-effective alternative, reducing construction and maintenance costs, and a sustainable practice, preserving non-renewable materials such as rocks and soils.
17

Efeitos da composição de resíduos de construção e demolição em seu comportamento mecânico para utilização em pavimentação / The effects of composition of construction and demolition waste on their mechanical behavior for use in paving

Matuella, Matheus Ferreira January 2017 (has links)
A indústria da construção civil utiliza grandes volumes de recursos naturais e, concomitantemente, produz elevadas quantidades de resíduos de construção e demolição (RCD), que são pouco reaproveitados e, às vezes, descartados de forma inadequada. Por reduzir a quantidade de matérias-primas extraídas da natureza, a construção de pavimentos aparece como destino nobre para os RCD. Contudo como esses materiais podem apresentar elevada heterogeneidade em sua composição, questiona-se se isso pode influenciar seu comportamento mecânico. A pesquisa relatada nesta dissertação buscou analisar as características físicas e comportamento mecânico de RCD de concreto (RCD cinza), e desse material misturado com RCD cerâmico (RCD vermelho). Acrescentando-se de 0 a 50% de tijolos maciços britados aos resíduos de concreto, reproduziram-se composições encontradas em obras civis. A partir de resultados de ensaios de granulometria, compactação, abrasão, compressão triaxial e módulo de resiliência (MR), compararam-se os comportamentos das mesmas. Com auxílio do software Everstress 5.0, foram feitas análises mecanísticas de pavimentos com bases compostas desses materiais, de forma que fossem estimados seus desempenhos frente a diferentes mecanismos de degradação. Observou -se que o aumento na porcentagem de RCD cerâmico afeta significativamente o comportamento mecânico do RCD misto, aumentando a perda de massa por abrasão e o teor de umidade ótimo de compactação, reduzindo o peso específico aparente seco máximo, a coesão e o módulo de resiliência e tornando o material menos dependente do estado de tensões. Conclui-se que a composição de resíduos de construção e demolição afeta seu comportamento mecânico e tem influência significativa no desempenho de pavimentos em que forem usados. Verifica-se que tanto os RCD cinza, quanto os mistos podem suportar as solicitações do tráfego, fortalecendo-se a filosofia de aliar a construção de pavimentos aptos estruturalmente a um modo de construir que contribua para a redução da exploração e degradação do meio ambiente. / The construction industry uses large volumes of natural resources and, at the same time, produces a high amount of construction and demolition waste (CDW), which are little reused and sometimes discarded inappropriately. In order to reduce the amount of raw materials extracted from nature, the construction of pavements appears as a noble destination for the use of CDW. However, since these materials may present high heterogeneity in their composition, it is questioned whether this may influence their mechanical behavior. The research reported in this dissertation aimed at analyzing the physical characteristics and mechanical behavior of recycled concrete aggregate (RCA) and this material mixed with crushed bricks. Adding from 0 to 50% of ceramic CDW to concrete residues, compositions found in civil works were reproduced. From the results of grain size distribution, abrasion, triaxial compression and resilience modulus tests, their behavior was compared. Using Everstress 5.0 software, mechanistic analysis of pavements with bases made of these materials were performed, so that their performances against different degradation mechanisms were estimated. It was observed that the increase in the percentage of ceramic CDW influences the behavior of the mixed CDW, increasing the abrasion mass loss and the optimum compaction moisture content, reducing the apparent maximum dry unit weight, cohesion and the modulus of resilience and making the material less dependent on the stress state. It is concluded that the composition of construction and demolition waste directly influences its mechanical behavior and has a significant influence on the performance of pavements in which they are used. Both RCA and mixed CDW have the potential to withstand traffic loads, strengthening the philosophy of combining the construction of pavements structurally capable with a construction mode that contributes to the reduction of exploration and degradation of the environment.
18

Impact of Forecasted Freight Trends on Highway Pavement Infrastructure

January 2016 (has links)
abstract: The major challenge for any pavement is the freight transport carried by the structure. This challenge is expected to increase in the coming years as freight movements are projected to grow and because these movements account for most of the load related distresses for the pavement. Substantial effort has been devoted to identifying the impacts of these future national freight trends with respect to the environment, economic growth, congestion, and reliability. These are all important aspects relating to the freight question, but an equally important and often overlooked aspect of this issue involves the impact of freight trends on the physical infrastructure. This study analyzes the impact of future freight traffic trends on 26 major interstates representing 68% of the total system mileage and carrying 80% of the total national roadway freight. The pavement segments were analyzed using the Mechanistic Empirical Pavement Design Guide software after collecting the relevant traffic, climate, structural, and material properties. Comparisons were drawn between the expected pavement performance using current design standards for traffic growth and performance predictions that incorporated more detailed freight projections which themselves considered job growth and six key drivers of freight movement. The differences in the resultant performance were used to generate maps that provide a bird’s eye view of locations that are especially vulnerable to future trends in freight movement. The analysis shows that the areas of greatest vulnerability include segments that are directly linked to the busiest ports, and surprisingly those from Atlantic and Central states that provide long distance connectivity, but do not currently carry the highest traffic volumes. / Dissertation/Thesis / Masters Thesis Civil and Environmental Engineering 2016
19

Efeitos da composição de resíduos de construção e demolição em seu comportamento mecânico para utilização em pavimentação / The effects of composition of construction and demolition waste on their mechanical behavior for use in paving

Matuella, Matheus Ferreira January 2017 (has links)
A indústria da construção civil utiliza grandes volumes de recursos naturais e, concomitantemente, produz elevadas quantidades de resíduos de construção e demolição (RCD), que são pouco reaproveitados e, às vezes, descartados de forma inadequada. Por reduzir a quantidade de matérias-primas extraídas da natureza, a construção de pavimentos aparece como destino nobre para os RCD. Contudo como esses materiais podem apresentar elevada heterogeneidade em sua composição, questiona-se se isso pode influenciar seu comportamento mecânico. A pesquisa relatada nesta dissertação buscou analisar as características físicas e comportamento mecânico de RCD de concreto (RCD cinza), e desse material misturado com RCD cerâmico (RCD vermelho). Acrescentando-se de 0 a 50% de tijolos maciços britados aos resíduos de concreto, reproduziram-se composições encontradas em obras civis. A partir de resultados de ensaios de granulometria, compactação, abrasão, compressão triaxial e módulo de resiliência (MR), compararam-se os comportamentos das mesmas. Com auxílio do software Everstress 5.0, foram feitas análises mecanísticas de pavimentos com bases compostas desses materiais, de forma que fossem estimados seus desempenhos frente a diferentes mecanismos de degradação. Observou -se que o aumento na porcentagem de RCD cerâmico afeta significativamente o comportamento mecânico do RCD misto, aumentando a perda de massa por abrasão e o teor de umidade ótimo de compactação, reduzindo o peso específico aparente seco máximo, a coesão e o módulo de resiliência e tornando o material menos dependente do estado de tensões. Conclui-se que a composição de resíduos de construção e demolição afeta seu comportamento mecânico e tem influência significativa no desempenho de pavimentos em que forem usados. Verifica-se que tanto os RCD cinza, quanto os mistos podem suportar as solicitações do tráfego, fortalecendo-se a filosofia de aliar a construção de pavimentos aptos estruturalmente a um modo de construir que contribua para a redução da exploração e degradação do meio ambiente. / The construction industry uses large volumes of natural resources and, at the same time, produces a high amount of construction and demolition waste (CDW), which are little reused and sometimes discarded inappropriately. In order to reduce the amount of raw materials extracted from nature, the construction of pavements appears as a noble destination for the use of CDW. However, since these materials may present high heterogeneity in their composition, it is questioned whether this may influence their mechanical behavior. The research reported in this dissertation aimed at analyzing the physical characteristics and mechanical behavior of recycled concrete aggregate (RCA) and this material mixed with crushed bricks. Adding from 0 to 50% of ceramic CDW to concrete residues, compositions found in civil works were reproduced. From the results of grain size distribution, abrasion, triaxial compression and resilience modulus tests, their behavior was compared. Using Everstress 5.0 software, mechanistic analysis of pavements with bases made of these materials were performed, so that their performances against different degradation mechanisms were estimated. It was observed that the increase in the percentage of ceramic CDW influences the behavior of the mixed CDW, increasing the abrasion mass loss and the optimum compaction moisture content, reducing the apparent maximum dry unit weight, cohesion and the modulus of resilience and making the material less dependent on the stress state. It is concluded that the composition of construction and demolition waste directly influences its mechanical behavior and has a significant influence on the performance of pavements in which they are used. Both RCA and mixed CDW have the potential to withstand traffic loads, strengthening the philosophy of combining the construction of pavements structurally capable with a construction mode that contributes to the reduction of exploration and degradation of the environment.
20

Análise estrutural de pavimentos de baixo volume de tráfego revestidos com solo modificado com cal considerando ensaios laboratoriais e monitoramento de trechos experimentais / Structural Analyze of low-volume roads covered with soil modified with lime with considering of laboratorial tests and monitoring of experimental sections

Katz, Leonardo Behak January 2013 (has links)
Os solos das regiões arrozeiras apresentam características geotécnicas inadequadas para uso como revestimentos primários de estradas. Isto força o transporte de materiais de jazidas distantes, o que, além de onerar o custo de construção, nem sempre é uma solução durável. Nesta tese relata-se uma pesquisa que apresenta uma solução para esse problema: a pavimentação de estradas de baixo volume de tráfego com solo local modificado com cal. Foram realizados estudos laboratoriais e de campo, e os resultados analisados através de uma abordagem mecanístico-empírica. Dois pavimentos experimentais com revestimentos de solo-cal foram construídos e monitorados próximo a Cebollatí, leste do Uruguai. Foram realizados ensaios de caracterização e comportamento mecânico do solo e de misturas de solo e cal, variando-se o teor de cal, o tempo de cura e a energia de compactação. Realizaram-se ensaios de módulo de resiliência, para o qual foi projetado, montado e operado o primeiro equipamento de ensaios de carga repetida na compressão triaxial do Uruguai. Também foram realizados ensaios de fadiga na compressão diametral para o solo modificado com 3% e 5% de cal, curado por 28 e 150 dias. Para entender o comportamento das camadas de solo modificado com cal submetidas ao tráfego, realizou-se uma análise conjunta dos resultados laboratoriais e do monitoramento dos trechos experimentais, com uso de modelos computacionais. Apesar das limitações construtivas, de terem sido liberados ao tráfego em plena safra e das más condições de drenagem da região, após 5 anos de trafego, os pavimentos não mostram trincas de fadiga ou afundamentos nas trilhas de roda. Assim, a pavimentação de estradas de baixo volume de tráfego em regiões arrozeiras com revestimentos de solo local modificado com cal provou ser uma alternativa economicamente vantajosa, por reduzir custos de construção e manutenção, e sustentável, por preservar materiais não-renováveis, como solos e rochas. / Soils in rice plantation areas generally present geotechnical characteristics unsuitable for use as primary wearing course of roads. Because of that, it is necessary to import materials from distant sites, a solution that, besides increasing construction cost, is rarely long-lasting. In this thesis a research on paving low volume roads with lime modified local soils is reported, in order to present an alternative solution to that problem. Both laboratory and field studies were carried out and the results were analyzed by means of a mechanistic-empirical approach. Two test sections with wearing courses made of lime modified soil were built and monitored close to Cebollatí, a village in the east of Uruguay. Previously, laboratory characterization and mechanical tests on samples of the sedimentary soil were carried out. Lime contents for mixtures were determined and the stress-strain-strength behavior of mixes with different levels of lime content, curing time and compaction energy was studied. In order to analyze the elastic behavior of the lime modified soil under traffic, resilient modulus tests were carried out. This motivated the design, assembly and use of the first equipment for triaxial compression repeated loading tests in Uruguay. Besides, stress controlled fatigue tests were performed on cylindrical specimens of soil modified with 3% and 5% of lime, cured for 28 and 150 days. The results of laboratory tests and field monitoring were analyzed using computational models. In spite of the difficulties faced during pavements construction, including heavy traffic in early days, and the poor drainage, after 5 years of service no cracks or ruts are seen on top of the test pavements. Therefore, paving low volume roads in rice plantation areas with lime modified wearing courses has proved to be a cost-effective alternative, reducing construction and maintenance costs, and a sustainable practice, preserving non-renewable materials such as rocks and soils.

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