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Hot Mix Asphalt (HMA) design has undergone years of development. Currently, many state agencies use the Superpave mix design method. While the Superpave mix design improved rutting, the implemented level 1 only considered volumetric properties and not mixture performance tests. Therefore, development in the asphalt community has addressed some of the issues with the Superpave mix design, e.g., cracking and raveling, with the Balance Mix Design (BMD) approaches. The Balance Mix Design incorporates performance testing elements that the level 1 Superpave mix design does not. The Virginia Department of Transportation (VDOT) aims to implement the Balance Mix Design by 2023. The objective of this thesis is to evaluate the initial frictional properties of mixes designed using the Balanced Mix Design method to verify that safety is not compromised to support the implementation of the BMD method within VDOT. It provides a further understanding of BMD mixtures surface properties provides insight into volumetric properties that may influence macrotexture. The thesis analyzed the initial friction and macrotexture of a series of experimental sections built to support VDOT BMD implementation efforts. A Side-Force Coefficient Road Investigation Machine (SCRIM) was used to measure friction and texture data on Control (Superpave Mix Design) and Balance Mix Design sections on several VDOT districts. Once the data was collected, it was analyzed using descriptive statistics and mean comparisons to determine any statistical differences in the friction and texture of the Control and BMD Mixes. The analysis showed that although statistically significant differences in friction and macrotexture were observed between some of the Superpave (Control) and Balance Mix Design mixes, the differences seem to be more prominent among districts than between the mix design method. In general, there were no difference in friction between control and BMD mixes in the same locations. On the other hand, there is statistically significant differences in the as-constructed macrotexture of Superpave and BMD mixes evaluated, with more BMD mixes having higher macrotexture than their control counterparts. Further analysis was conducted to create a macrotexture prediction model based on production volumetric properties obtained from VDOT databases. The model provided an initial assessment of the main HMA properties that influence MPD. A comparison of the macrotexture of the constructed in the various locations found that there is strong statistical evidence that the mean macrotexture of the pavement constructed in the various location was different. The analysis also showed that some projects produced sections with more uniform macrotexture than others. Comparison of mixes constructed in different years does not suggest any significant differences over the three-construction season evaluated. / Master of Science / Hot Mix Asphalt (HMA) is derived from various mix designs over the last hundred years. Currently, many highway agencies use the Superpave Mix Design in roadway development but only his basic level has been implemented. Most agencies do not use mechanical tests to verify that the mixes will perform properly when place on the pavement. To address some of issues with the current mix design approach, highway agencies have started to implement and use the Balance Mix Design (BMD). The Balance Mix Design incorporates performance tests for distresses such as rutting and cracking where the Superpave Mix Design did not. The Virginia Department of Transportation (VDOT) is working towards implementing the Balance Mix Design by 2023. The objective of this thesis is to evaluate the initial frictional properties of mixes designed using the Balanced Mix Design method to verify that safety is not compromised to support the implementation of the BMD method within VDOT. It helps agencies understand of BMD mixtures surface properties and what mix design properties may influence the safety of the road surface. The thesis analyzed the initial friction and macrotexture, properties that allow the vehicles to break and maintain control on curves, of a series of experimental sections built to support VDOT BMD implementation efforts. The Side-Force Coefficient Road Investigation Machine (SCRIM) is a large vehicle that continuously measures the pavement surface for friction, texture, and other elements using a skewed wheel and a laser system. The SCRIM was used in this thesis to measure friction and texture data on Control (Superpave Mix Design) and Balance Mix Design sections constructed on several VDOT districts. The data were analyzed using statistical analysis to determine any differences in the friction and texture of the Control and BMD Mixes. In general, there are no differences in friction between control and BMD mixes in the same locations. On the other hand, the analysis showed significant differences in the as-constructed macrotexture of Superpave and BMD mixes evaluated. In general, more BMD mixes had higher macrotexture than their control counterparts. Further analysis was conducted to create a macrotexture prediction model based on production volumetric properties obtained from VDOT databases. A comparison of the macrotexture of the constructed in the various locations found that there is strong statistical evidence that the average macrotexture of the pavement constructed in the various location was different.

Pavement macrotexture has been shown to influence a range of safety and comfort issues including wet weather friction, splash and spray, ambient and in-vehicle noise, tire wear, and rolling resistance. While devices and general guidance exist to measure macrotexture, the wide-scale collection and use of macrotexture is neither mandated nor is it typically employed in the United States. This work seeks to improve upon the methods used to calibrate, collect, pre-process, and distill macrotexture data into useful information that can be utilized by pavement managers. This is accomplished by 1. developing a methodology to evaluate and compare candidate data collection devices; 2. plans and procedures to evaluate the accuracy of high-speed network data collection devices with reference surfaces and measurements; 3. the development of a method to remove erroneous data from emerging 3-D macrotexture sensors; 4. development of a model to describe the change in macrotexture as a function of traffic; 5.finally, distillation of the final collected pavement surface profiles into parameters for the prediction of important pavement surface properties aforementioned. Various high-speed macrotexture measurement devices were shown to have good repeatability (between 0.06 to 0.09mm MPD) and interchangeability of single-spot laser dfevices was demonstrated via a limits of agreement analysis. The operational factors of speed and acceleration were shown to affect the resulting MPD of several devices and guidelines are given for vehicle speed and sensor exposure settings. Devices with single spot and line lasers were shown to reproduce reference waveforms on manufactured surfaces within predefined tolerances. A model was developed that predicts future macrotexture levels (as measured by RMS) for pavements prone to bleeding due to rich asphalt content. Finally, several previously published macrotexture parameters along with a suite of novel parameters were evaluated for their effectiveness in the prediction of wet weather friction and certain types of road noise. Many of the parameters evaluated outperformed the current metrics of MPD and RMS. / Doctor of Philosophy

La présente thèse concerne l'adhérence des pneumatiques avec les chaussées routières, et la possibilité de prévoir son évolution à l'aide d'essais de laboratoire et de modélisations. Tout d'abord, une méthodologie originale de polissage et de mesure de l'adhérence en laboratoire est présentée ; elle s'appuie sur la machine de Wehner et Schulze, développée en Allemagne. Grâce à elle, on peut mesurer l'évolution du coefficient de frottement avec la durée du polissage. Des chantiers routiers sont suivis dans le temps, afin de comparer la simulation en laboratoire et l'évolution réelle de l'adhérence. Parallèlement à la simulation expérimentale, des lois d'évolution sont établies. Un modèle à cinq paramètres est tout d'abord proposé, que l'on tente de relier aux caractéristiques des granulats (PSV, diamètre maximal, microtexture, etc.). Ensuite, un modèle plus physique est ébauché, explicitant les mécanismes de vieillissement et de décapage du bitume, et de polissage des granulats. Un coefficient d'équivalence entre le trafic poids lourd et le nombre de cycles d'usure en laboratoire est proposé, devant permettre à terme de choisir entre différents matériaux de couche de surface, et de prévoir l'évolution de l'adhérence d'une chaussée neuve. Enfin, les profils de surface sont examinés à différents états de polissage, dans le but de relier l'évolution de l'adhérence aux paramètres de rugosité, et aux caractéristiques des granulats (PSV, MDE, LA).

Les matériaux cristallins, notamment métalliques, sont des matériaux hétérogènes. Leurs propriétés macroscopiques sont fondamentalement déterminées par leurs caractéristiques microstructurales. L'étude des mécanismes opérant à l'échelle du grain permet de mieux comprendre et mieux contrôler les caractéristiques des pièces fabriquées afin de réduire leur coût et optimiser leur performance. Cette thèse s'inscrit dans le cadre de la méthode dite "CPFEM'' qui couple la plasticité cristalline à la méthode des Eléments finis (EF). L'objectif de ce travail est d'étudier les hétérogénéités à l'échelle du grain au sein d'agrégats polycristallins soumis à de grandes déformations. Pour ce faire, une représentation explicite de la microstructure est nécessaire. Le travail réalisé, ainsi que ce manuscrit, s'articule autour de deux axes principaux: i) la mise en place d'un cadre numérique robuste adapté à des calculs de microstructure intensifs en grandes déformations; ii) la validation de ce cadre à travers différents cas tests, qui permettent, notamment, d'étudier les hétérogénéités locales. Dans le chapitre 2, le comportement du matériau est modélisé par une loi élastoviscoplastique cristalline, qui ne prend cependant pas en compte le développement d'une sous-structure dans sa formulation. Cette loi est couplée à une formulation EF mixte en vitesse pression. L'approche EF, détaillée dans le chapitre 3, peut être considérée comme le modèle polycristallin idéal vu le respect, au sens numérique faible, de l'équilibre des contraintes et la compatibilité des déformations. Dans le chapitre 4, l'approche utilisée pour construire, représenter et discrétiser un volume polycristallin est détaillée. La microstructure est représentée, soit par des polyèdres de Voronoi, soit par des voxels, si elle est construite à partir de données expérimentales. L'agrégat polycristallin est discrétisé avec une approche "monolithique'', où un seul maillage, non structuré et non-conforme aux interfaces entre les grains, est utilisé. Une approche level set permet alors de décrire l'interface entre les grains de façon implicite et sert de base pour la construction d'un maillage adaptatif anisotrope. Le remaillage, avec un transport approprié des variables du problème, se fait de façon naturelle et automatique si la carte de métrique, associée au maillage, est calculée avant la procédure de remaillage. Dans le chapitre 5, les hétérogénéités inter- et intragranulaire sont appréhendées à travers une étude de la distribution d'une fraction de l'énergie de déformation. Cette fraction est considérée, dans une première approche, comme étant représentative de l'énergie stockée durant la déformation. Une analyse de sensibilité, au degré et au type de maillage utilisé, permet de mettre en évidence l'apport d'une stratégie de maillage anisotrope. Ces données locales sont particulièrement importantes à calculer lors de la déformation d'agrégats polycrystallins si l'objectif est de modéliser le phénomène de recristallisation statique qui suit l'étape de déformation. Un cas test 3D permet d'illustrer le chaînage de la simulation de la déformation et de la recristallisation, toutes deux réalisées dans le même cadre numérique. Dans le chapitre 6, notre approche numérique est, dans un premier temps, validée à l'aide d'un cas test de laminage pour un polycrystal statistiquement représentatif d'une texture expérimentale. Une réduction d'épaisseur de plus de 90 % est réalisée. Le remaillage, dans ce type d'application, s'avère plus que nécessaire. Dans la seconde partie de ce chapitre, une étude approfondie de la microtexture, développée au sein de microstructures virtuelles, est effectuée. Dans ce cas, ces microstructures "digitales'' correspondent à une microstructure réelle dans un sens discret. Les prédictions de désorientations, d'orientations cristallographiques moyennes ainsi que les cartes d'orientation 2D virtuelles, sont comparés à l'expérience à l'échelle de chaque grain, mettant ainsi en évidence les facteurs à l'origine de certaines des différences observées.

Submitted by Geyciane Santos (geyciane_thamires@hotmail.com) on 2015-09-30T14:23:40Z No. of bitstreams: 1 Dissertação - Washington Luiz Pinto Filho.pdf: 8211076 bytes, checksum: 5b0146ee71fe71f4ffea30a9fca0f822 (MD5) / Approved for entry into archive by Divisão de Documentação/BC Biblioteca Central (ddbc@ufam.edu.br) on 2015-10-02T20:44:54Z (GMT) No. of bitstreams: 1 Dissertação - Washington Luiz Pinto Filho.pdf: 8211076 bytes, checksum: 5b0146ee71fe71f4ffea30a9fca0f822 (MD5) / Approved for entry into archive by Divisão de Documentação/BC Biblioteca Central (ddbc@ufam.edu.br) on 2015-10-06T19:53:40Z (GMT) No. of bitstreams: 1 Dissertação - Washington Luiz Pinto Filho.pdf: 8211076 bytes, checksum: 5b0146ee71fe71f4ffea30a9fca0f822 (MD5) / Made available in DSpace on 2015-10-06T19:53:40Z (GMT). No. of bitstreams: 1 Dissertação - Washington Luiz Pinto Filho.pdf: 8211076 bytes, checksum: 5b0146ee71fe71f4ffea30a9fca0f822 (MD5) Previous issue date: 2013-11-29 / Não informada / The city of Manaus has the highest average growth rates of the fleet, according to the DENATRAN. Over the past 10 years, the fleet of cars rose from 124,840 (2003) to 297,473 cars (2013) and 3,179 buses (2003) to 7,398 buses (2013). This equates to a 138% increase. Moreover, although, according to DENATRAN in 2003, Manaus was 220,816 vehicles. In 2013, Manaus already has 551,455 registered vehicles in its municipal fleet, which equates to an increase of almost 150%. As a result of this growth, the city roads are presented with its ability to flow and dead, visually, with their decks completely deformed. In this sense, we tried to carry this research, a structural evaluation of pavements of the main streets of the town (Av. Constantino Nery, Avenida Djalma Batista, Recife Av, Av and Av Efigênio Sales Paraíba), employing the technique FWD (Falling Weight Deflectometer) in the diagnosis of the pavement structures of these pathways. The results showed that the structures of those decks still have the condition to withstand the demands of traffic load applied to them, since their structural quality obtained by the mentioned technique, presented in good condition, according to the floors they presented deflections smaller than the allowed maximum, and radii of curvature much greater than 100 m. In addition, analysis was performed of the safety of the coating with respect to tire-pavement grip, which presented values for microtexture and macrotexture well outside the ranges recommended by the standards. / A cidade de Manaus apresenta uma das maiores taxas de crescimento médio da frota de veículos, segundo dados do DENATRAN. Nos últimos 10 anos, a frota de automóveis aumentou de 124.840 (2003) para 297.473 automóveis (2013) e 3.179 ônibus (2003) para 7.398 ônibus (2013). Isto equivale a um aumento de 138 %. Ademais, ainda, segundo o DENATRAN, em 2003, Manaus tinha 220.816 veículos. Em 2013, Manaus já possui 551.455 veículos registrados na sua frota municipal, o que equivale a um aumento de quase 150 %. Como consequência deste crescimento, as vias da cidade apresentam-se com sua capacidade de fluxo inoperante e, visualmente, com seus pavimentos totalmente deformados. Neste sentido, procurou-se realizar, nesta pesquisa, uma avaliação estrutural dos pavimentos das principais vias da cidade (Av. Constantino Nery, Av. Djalma Batista, Av. Recife, Av. Paraíba e Av. Efigênio Sales), empregando a técnica FWD (Falling Weight Deflectometer) no diagnóstico das estruturas dos pavimentos das referidas vias. Os resultados obtidos mostraram que as estruturas daqueles pavimentos ainda apresentam a condição de suportar as solicitações de carga de tráfego a elas aplicadas, visto que sua qualidade estrutural, obtida pela técnica mencionada, apresentou-se em boas condições, em função dos pavimentos terem apresentado deflexões máximas inferiores às admissíveis, bem como raios de curvatura muito superiores a 100 m. Como complemento à análise estrutural, realizou-se análise das condições funcionais do revestimento com relação à aderência pneu-pavimento, a qual apresentou valores para microtextura e macrotextura bem fora dos intervalos recomendados pelas normas.

One of the most important objectives for transportation engineers is to understand pavement surface properties and their positive and negative effects on the user. This can improve the design of the infrastructure, adequacy of tools, and consistency of methodologies that are essential for transportation practitioners regarding macrotexture characterization. Important pavement surface characteristics, or tire-pavement interactions, such as friction, tire-pavement noise, splash and spray, and rolling resistance, are significantly influenced by pavement macrotexture. This dissertation compares static and dynamic macrotexture measurements and proposes and enhanced method to quantify the macrotexture. Dynamic measurements performed with vehicle-mounted lasers have the advantage of measuring macrotexture at traffic speed. One drawback of these laser devices is the presence of 'spikes' in the collected data, which impact the texture measurements. The dissertation proposes two robust and innovative methods to overcome this limitation. The first method is a data-driven adaptive method that detects and removes the spikes from high-speed laser texture measurements. The method first calculates the discrete wavelet transform of the texture measurements. It then detects (at all levels) and removes the spikes from the obtained wavelet coefficients (or differences). Finally, it calculates the inverse discrete wavelet transform with the processed wavelet coefficients (without outliers) to obtain the Mean Profile Depth (MPD) from the measurements with the spikes removed. The method was validated by comparing the results with MPD measurements obtained with a Circular Texture Meter (CTMeter) that was chosen as the control device. Although this first method was able to successfully remove the spikes, it has the drawback that it depends on manual modeling of the distribution of the wavelet coefficients to correctly define an appropriate threshold. The next step of this dissertation proposes an enhanced to the spike removal methodology for macrotexture measurements taken with high-speed laser devices. This denoising methodology uses an algorithm that defines the distribution of texture measurements by using the family of Generalized Gaussian Distributions (GGD), along with the False Discovery Rate (FDR) method that controls the proportion of wrongly identified spikes among all identified spikes. The FDR control allows for an adaptive threshold selection that differentiates between valid measurements and spikes. The validation of the method showed that the MPD results obtained with denoised dynamic measurements are comparable to MPD results from the control devices. This second method is included as a crucial step in the last stage of this dissertation as explained following. The last part of the dissertation presents an enhanced macrotexture characterization index based on the Effective Area for Water Evacuation (EAWE), which: (1) Estimates the potential of the pavement to drain water and (2) Correlates better with two pavement surface properties affected by macrotexture (friction and noise) that the current MPD method. The proposed index is defined by a three-step process that: (1) removes the spikes, assuring the reliability of the texture profile data, (2) finds the enveloping profile that is necessary to delimit the area between the tire and the pavement when contact occurs, and (3) computes the EAWE. Comparisons of current (MPD) and proposed (EAWE) macrotexture characterization indices showed that the MPD overestimates the ability of the pavement for draining the surface water under a tire. / Ph. D.

O gerenciamento de uma malha rodoviária engloba avaliações constantes das condições estruturais e, principalmente, funcionais. Assim sendo, uma forma de coleta automatizada, realizada em velocidades de tráfego, em que a influência humana possa ser desconsiderada, está em desenvolvimento na engenharia rodoviária brasileira, assim como é visto internacionalmente. O presente trabalho tem como objetivo a contribuição para o processo de avaliação funcional de pavimentos através do estudo sobre a aplicabilidade do processo de inventário funcional de pavimentos rígidos com o emprego do equipamento Pavement Scanner. Para tanto, após a revisão bibliográfica sobre a sistemática de inventário de pavimentos rígidos e também sobre o equipamento Pavement Scanner, seções testes foram definidas e avaliadas de acordo com o método tradicional de levantamento da superfície do pavimento (ICP - DNIT 062/PRO, DNIT 060/PRO), o método volumétrico tradicional de mancha de areia para avaliação de macrotextura (ASTM E 965/96), através de imageamento com análise de imagens obtidas no trecho e sob a utilização do equipamento Pavement Scanner. Com os resultados foi realizada uma análise estatística destas técnicas utilizadas, demonstrando a viabilidade de utilização do equipamento e do procedimento de análise adotado. / The management of a road network encompasses constant assessments of structural conditions and, above all, functional conditions. Thus, a form of automated survey, carried out at traffic speeds, in which human influence can be unconsidered, is under development in Brazilian road engineering, as it is seen internationally. This present work aims to contribute to the process of functional assessment of pavements through the study of applicability of the functional inventory process of rigid pavements with the use of Pavement Scanner equipment. In order to do so, after the literature review of rigid pavement inventory and Pavement Scanner equipment, test sections were defined and evaluated according to the traditional method of surface survey (ICP - DNIT 062 / PRO, DNIT 060 / PRO), the traditional sand patch volumetric method for the evaluation of macrotexture (ASTM E 965/96), through imaging analysis from the test sections and under the use of Pavement Scanner equipment. With the results, a statistical analysis of these techniques were performed, demonstrating the feasibility of using the equipment and the analysis procedure adopted.

O gerenciamento de uma malha rodoviária engloba avaliações constantes das condições estruturais e, principalmente, funcionais. Assim sendo, uma forma de coleta automatizada, realizada em velocidades de tráfego, em que a influência humana possa ser desconsiderada, está em desenvolvimento na engenharia rodoviária brasileira, assim como é visto internacionalmente. O presente trabalho tem como objetivo a contribuição para o processo de avaliação funcional de pavimentos através do estudo sobre a aplicabilidade do processo de inventário funcional de pavimentos rígidos com o emprego do equipamento Pavement Scanner. Para tanto, após a revisão bibliográfica sobre a sistemática de inventário de pavimentos rígidos e também sobre o equipamento Pavement Scanner, seções testes foram definidas e avaliadas de acordo com o método tradicional de levantamento da superfície do pavimento (ICP - DNIT 062/PRO, DNIT 060/PRO), o método volumétrico tradicional de mancha de areia para avaliação de macrotextura (ASTM E 965/96), através de imageamento com análise de imagens obtidas no trecho e sob a utilização do equipamento Pavement Scanner. Com os resultados foi realizada uma análise estatística destas técnicas utilizadas, demonstrando a viabilidade de utilização do equipamento e do procedimento de análise adotado. / The management of a road network encompasses constant assessments of structural conditions and, above all, functional conditions. Thus, a form of automated survey, carried out at traffic speeds, in which human influence can be unconsidered, is under development in Brazilian road engineering, as it is seen internationally. This present work aims to contribute to the process of functional assessment of pavements through the study of applicability of the functional inventory process of rigid pavements with the use of Pavement Scanner equipment. In order to do so, after the literature review of rigid pavement inventory and Pavement Scanner equipment, test sections were defined and evaluated according to the traditional method of surface survey (ICP - DNIT 062 / PRO, DNIT 060 / PRO), the traditional sand patch volumetric method for the evaluation of macrotexture (ASTM E 965/96), through imaging analysis from the test sections and under the use of Pavement Scanner equipment. With the results, a statistical analysis of these techniques were performed, demonstrating the feasibility of using the equipment and the analysis procedure adopted.

Esta pesquisa foi baseada em um projeto de Stone Matrix Asphalt - SMA na faixa 0/8S com asfalto CAP 20, feito para a execução de revestimento delgado em trecho experimental na Rodovia Presidente Dutra, ligando São Paulo ao Rio de Janeiro. A ocorrência de alguns defeitos neste trecho experimental motivou o estudo de misturas SMA 0/8S alternativas empregando dois asfaltos convencionais: CAP 20 e CAP 50/60, e dois modificados por polímeros: um com 3,0% de SBS e outro com 6,5% de SBS. Foram realizados ensaios laboratoriais para a verificação da dosagem das misturas asfálticas e determinação de propriedades mecânicas em laboratório por meio de ensaios de deformação permanente em trilha de roda, de resistência à tração por compressão diametral e de módulo de resiliência. Observou-se que o uso de asfalto modificado por polímero e do asfalto convencional CAP 50/60 acarreta uma redução significativa de afundamentos em trilha de roda. O módulo de resiliência a 25°C também apresenta redução de valor nas amostras com asfalto modificado por polímero e com CAP 50/60, em comparação com o convencional CAP 20. A resistência à tração sofre pouca variação quando se comparam os asfaltos empregados, considerando-se ensaios realizados na mesma temperatura. Foram feitos ensaios em campo para a avaliação funcional e de aderência no trecho experimental da Rodovia Presidente Dutra, tendo sido realizados monitoramentos logo após a execução do trecho e decorridos 2 anos e 7 meses de operação. Os resultados demonstraram que o revestimento do trecho experimental apresenta atualmente poucos defeitos de superfície, com fechamento da macrotextura nas trilhas de roda e pequena diminuição do conforto ao rolamento. / This research was based on a Stone Matrix Asphalt SMA in the band 0/8S design made with asphalt binder AC 20, used as a thin wearing course of a test section on the Presidente Dutra Highway, that connects São Paulo to Rio de Janeiro. The occurrence of some distresses in the test section motivated the study of alternative SMA 0/8S mixtures using two conventional asphalt binders: AC 20 and AC 50/60, and two modified by polymer: one with 3.0% of SBS and other with 6.5% of SBS. Laboratory tests were conducted to verify the mix design and to determine their mechanical behavior such as the resistance against rutting, the indirect tensile strength and the resilient modulus. It was observed that the use of SBS polymer modified binders and asphalt binder AC 50/60 causes a significant reduction of rutting. The resilient modulus at 25°C also presents a reduction in the samples with SBS polymer modified binders and AC 50/60 in comparison with AC 20. The indirect tensile strength suffers little variation across the different types of asphalt binders, tested at the same temperature. Field tests related to functional evaluation and skid-resistance of the test section were carried out. The test section was monitored immediately following the construction and after 2 years and 7 months of continuous use. The results showed that the wearing coarse presented a few distresses in the surface, in particular a reduction of the macrotexture at the wheel tracks and a slight worsening of the riding quality.