Content uploaded by Jorge C. Pais
Author content
All content in this area was uploaded by Jorge C. Pais on Apr 27, 2019
Content may be subject to copyright.
Effect of Aggregate Gradation on Fatigue Life of Asphalt Concrete Mixes
Abstract
Four-point bending fatigue tests following the Strategic Highway Research Program (SHRP) M009 test protocol were executed to investigate to what extent gradation has an effect on fatigue performance of asphalt aggregate mixes. Gradations and mixes were selected that would satisfy all volumetric Superpave designs passing below the restricted zone. Other mixes were prepared with gradations passing through and above the restricted zone. The measured fatigue lives of 130 actual laboratory tests were compared with predictions by the Shell, Asphalt Institute, and SHRP-A003A fatigue-predictive equations.
... From the aggregate gradation design point of view, it is imperative that aggregate gradations which can form an 23 interlocked structure for proper load transfer and which have the void volume to hold more mastic are to be designed to binder stiffness [4]. Only limited literature [5,2,3] are available to link the fatigue characteristics of bituminous 28 mixtures having different gradation designs. In such cases also, gradations that can accommodate more binder content 29 are documented to exhibit better fatigue behaviour [5]. ...
... Only limited literature [5,2,3] are available to link the fatigue characteristics of bituminous 28 mixtures having different gradation designs. In such cases also, gradations that can accommodate more binder content 29 are documented to exhibit better fatigue behaviour [5]. Most of the studies predominantly used dense gradations to 30 evaluate fatigue performance. ...
... Depending on the mode of testing, various approaches can be adopted to estimate the fatigue characteristics of bituminous mixtures from the laboratory test data. Various researches[5,1] and agencies have given the fatigue prediction equations to estimate fatigue life of bituminous mixtures. These equations are functions of applied strain or strain, flexural modulus and volumetric measures such as binder content and VFA. ...
... [1][2][3][4][5]. Numerous studies have employed these empirical phenomenological models to calculate and evaluate the fatigue lives of various asphalt-based composites [6][7][8][9][10][11]. Additionally, some researchers have proposed the use of strain energy indicators, such as dissipated strain energy or the plateau value of the dissipated strain energy ratio, to replace the loading term in the power function fatigue life model, considering the relationship between energy dissipation and fatigue damage evolution in asphalt-based composites [12][13][14][15][16]. ...
Asphalt-based composites gradually reach the end of their life as the service time increases, which directly leads to fatigue failure of the pavement structure. However, there is currently a lack of a fatigue life model for asphalt-based composites that has a clear physical interpretation. To address this issue, a viscoelastic fracture mechanics-based (VEFM) fatigue life model is proposed to predict the fatigue failure life for asphalt-based composites in this study. The VEFM fatigue life model was established within a viscoelastic fracture mechanics framework and was applied to two types of asphalt-filler composite systems (AFCS). To obtain the model parameters and verify the proposed model, various tests including linear amplitude sweep tests, time sweep tests at low-stress levels and high-stress levels, as well as surface energy tests were conducted on AFCS. The results indicate that the established VEFM fatigue life model can be expressed as a function of the loading level, viscoelastic fracture parameters, initial shear modulus, and surface energy. The initial edge flow of AFCS increases with the temperature and has minimal effect on the fatigue life throughout the fatigue process. A critical fatigue failure point is defined by the curve of damage rate and damage density. The fatigue life of AFCS increases with the temperature while decreasing with the loading level.
... Segundo diversos investigadores que utilizaram este tipo de ensaio para avaliar o comportamento de misturas betuminosas à fadiga (Schmidt, 1971, Kennedy & Anagnos, 1983, Khosla & Omer, 1985, Scholz et al., 1989, Kim et al., 1992, Khalid, 2000ae Batista, 2004 Sousa et al. (1998), Pais et al. (2002), Capitão & Santos (2005), e Batista et al. (2006). A nível internacional, referem-se os estudos de Tayebali et al. (1992), , Deacon et al. (1994), Harvey et al. (1994b), Harvey & Tsai (1996), Read & Brown (1996), Radziszewski (1997), Read & Collop (1997) Dos ensaios contemplados na norma, aborda-se a metodologia de ensaio que a mesma preconiza para o ensaio de flexão em quatro pontos de um provete prismático simplesmente apoiado. ...
Esta dissertação tem como objetivo o estudo da resistência à fadiga de misturas betuminosas com betume modificado com alta percentagem de borracha (BMBAP).
A resistência à fadiga das misturas betuminosas com BMBAP foi avaliada através do ensaio de flexão em quatro pontos, a extensão controlada, com a aplicação de carregamento sinusoidal com diferentes frequências, de acordo com o procedimento de ensaio da norma europeia EN 12697-24:2004.
Nesta avaliação foram utilizadas quatro misturas betuminosas com BMBAP: de obra,
foram estudadas duas misturas betuminosas, sendo uma aberta e outra rugosa com granitos; de laboratório, foram utilizadas duas misturas betuminosas, uma aberta com granitos e outra rugosa com seixos. Na avaliação do comportamento à fadiga foi averiguado o efeito do envelhecimento para a mistura betuminosa com seixos, simulado em laboratório.
Os resultados obtidos mostraram, em geral, um desempenho à fadiga adequado para as misturas estudadas. Os ensaios realizados permitiram evidenciar uma clara influência da frequência de ensaio e, no caso específico das misturas rugosas, uma baixa sensibilidade ao envelhecimento.
The main objective of this dissertation is to study the fatigue resistance of bituminous mixtures with high content of crumb rubber (BMBAP).
The fatigue behaviour evaluation of the bituminous mixtures with BMBAP was carried out through four point bending fatigue test, with controlled strain, applying a sinusoidal load with different frequencies, according to the European standard EN 12697-24:2004.
For assessing the fatigue behaviour of this mixtures, four bituminous mixtures with high content of crumb rubber were used: two field bituminous mixtures – an open-graded and a gap-graded – both with granite aggregates; and two laboratory manufactured bituminous mixtures – an open-graded with granite aggregates and another one gap-graded with natural gravel aggregates. Furthermore, the effect of laboratory ageing on the bituminous mixture with natural gravel, was analysed.
The obtained results showed in general an adequate fatigue performance for the mixtures studied. The work carried out revealed a clear influence of the frequency test, but also a decrease of the ageing sensibility in the specific case of the gap-graded mixtures.
... Kireçtaşında ise yüksek stabilite alt (kaba) gradasyon ile sağlanmıştır [14]. Daha ince agrega gradasyonu ile daha iyi yorulma performansı elde edilebilmektedir [15]. Sıkışmış karışımda agregalar arası boşluk yüzdesinin ve akmanın agrega gradasyonu inceldikçe arttığı görülmüştür [9,16]. ...
Bu çalışmada, agrega gradasyonunun bitümlü sıcak karışımların fiziksel özellikleri üzerindeki etkilerinin araştırılması amaçlanmıştır. Bu doğrultuda, 2013 yılı Karayolu Teknik Şartnamesinde binder tabakası için tanımlanan gradasyon zarfı esas alınmıştır. Gradasyon zarfına ait ortalama, alt limit, üst limit değerleri ile birlikte alt ve üst limitlerin % 7 oranında ötelenmesiyle elde edilen beş farklı agrega gradasyonu oluşturulmuş ve her biri için ayrı ayrı Marshall tasarımları yapılmıştır. Gradasyon zarfının dışındaki değerler, çalışma esnasında oluşabilecek gradasyon hatalarının bitümlü karışımda meydana getirebileceği performans değişimlerinin öngörülebilmesi amacıyla çalışmaya dahil edilmiştir. Elde edilen test verilerine göre agrega gradasyonunun bitümlü sıcak karışımların stabilite, akma, birim ağırlık (Dp), hava boşluğu oranı (Vh), bitümle dolu boşluk oranı (Vf), agregalar arasındaki boşluk oranı (VMA) ve Marshall katsayısı üzerindeki etkileri değerlendirilmiştir. Agrega dane boyutunun ortalama gradasyona kıyasla artmasının veya azalmasının Dp ve Vf değerlerinde azalma, VMA ve Vh değerlerinde artış meydana getirdiği belirlenmiştir. Bununla birlikte, gradasyon zarfının üst limitine doğru stabilite değerlerinin arttığı görülmüştür.
... M. Z. Júnior et al., 2019). Lucas Jùnior et al., (2020) ont prouvé que la résistance à la fatigue de l'enrobé en traction-compression est plus impactée par les propriétés d'adhérence granulat-liant que par la morphologie du squelette granulaire (Cui et al., 2014;Júnior et al., 2019;Zhou et al., 2021 (Carswell et al., 1997;Sousa et al., 1998). L'enrobé constitué de gros grain montre une bonne résistance à la fatigue sous la flexion 4-points. ...
Pour toute société florissante, disposer de meilleures infrastructures routières et de transport est essentiel non seulement pour la mobilité des personnes et des biens, mais aussi pour la croissance économique et une meilleure qualité de vie. Il est donc important d'avoir de meilleures conditions routières afin de maintenir un niveau de service acceptable. Cette étude vise à améliorer les outils de dimensionnement des chaussées routières en service et à optimiser leur entretien. Dans ce contexte, la compréhension des mécanismes de fissuration des matériaux de chaussée en service et le suivi de l'évolution des mécanismes d'endommagement et de vieillissement sont parmi les facteurs clés pour améliorer la modélisation des chaussées anciennes et le calcul de leur durée de vie en fatigue résiduelle. Cette thèse est réalisée dans le but d'étudier le vieillissement et l'endommagement des matériaux bitumineux à l'aide d'une approche de Contrôle Non Destructif (CND) et de modélisation hétérogène de leur comportement en fatigue. La partie expérimentale est principalement basée sur des mesures de propagation des ondes ultrasonores dans le matériau afin de caractériser ses propriétés mécaniques résiduelles. Les signaux enregistrés à partir de l'instrumentation acoustique et mécanique sont analysés pour proposer de nouveaux critères de détermination de la durée de vie en fatigue. L'approche utilisée dans la partie numérique est initialement basée sur une génération de champs de propriétés hétérogènes pour créer une microstructure hétérogène virtuelle (agrégats et matrice). Ces champs sont ensuite utilisés dans un modèle thermomécanique couplant les effets de l'auto- échauffement et de l'endommagement permettant de simuler le phénomène de fatigue des enrobés bitumineux sous sollicitation cyclique. Une approche d’optimisation Simplexe est utilisée afin de caler les paramètres des modèles d'endommagement sur des résultats expérimentaux
... However, for both types of capsules used, the number of pigmented mastic instances was significantly greater in AC 14. It is commonly accepted that the aggregate gradation of bituminous mixtures affects the damage extent and the evolution with loading due to the differences in the interlocking of mineral particles and the binder thickness around particles [26,27]. Therefore, the aggregate gradation is likely to affect capsule damage occurrence and, in the case of calcium alginate capsules, which hold the rejuvenator in a multi-cavity structure, the load transfer between aggregate particles and capsules in contact is extremely important. ...
Despite asphalt self-healing with encapsulated rejuvenators having been intensively researched over the last decade, there is still uncertainty about the performance advantages granted by this technology. As a way of adding to the existing set of research methodologies, this study aimed to test the feasibility of a visual method to investigate the working mechanism of encapsulated rejuvenators in the bituminous mixture. For this purpose, clear bituminous mixtures were produced using a colorless synthetic binder and a pigment was added to the rejuvenator incorporated in the calcium alginate capsules. The internal structure of the bituminous mixtures containing these capsules was inspected both on loaded and unloaded specimens. The colored rejuvenator was also directly added to cracked specimens and its distribution was studied, along with the interaction between the rejuvenator and the synthetic binder. The results show that the rejuvenator could modify the binder to a limited extent, and the bituminous mixtures containing capsules showed evidence of rejuvenator release. It is demonstrated that the aggregate gradation of mixtures has a significant effect on capsule damage and rejuvenator release. However, the pigment can be filtrated from the rejuvenator by the capsule polymer structure and the asphalt. Even though the methodology presented some constraints, it has been proven to be capable of achieving the initial goal, while also acting as an important first step in the visual study of rejuvenator release in asphalt.
... In this context, it is interesting to observe that the similarity in fatigue behavior of both mixtures occurs even with the modified mixture having lower amount of available asphalt binder, a factor that has an unfavorable impact on the fatigue performance of asphalt materials [108,109]. This is because, for this research, the incorporation of fibers was carried out by weight of binder during the asphalt concrete mixing process, resulting in increase in the specific surface area to be covered by the binder, and consequently, in lower asphalt binder content compared to the reference mixture, since both mixtures have asphalt binder content of 4.65 % in relation to the weight of mineral aggregates. ...
This research aimed to increase the healing capacity and mechanical performance of an asphalt mixture based on the incorporation of two conductive agents at different levels, steel wool in the microstructure and carbon nanotube in the asphalt nanostructure. Two asphalt mixtures were produced: a reference without additions and another modified with 1% carbon nanotube and 16% fiber/steel wool. Furthermore, additions increased the normalized healing/repair of the asphalt mixture by 49.67%. It could be concluded that the associated incorporation of steel wool and carbon nanotube enhances the healing capacity of the asphalt matrix and, consequently, is beneficial for its mechanical performance.
... Therefore, this paper systematically investigated the effect of CNT with different contents and sizes, functional groups and coating layers on the compressive fatigue performance of cementitious composites, including fatigue life, fatigue strength and fatigue deformation behavior. The cementitious composites were fabricated by using low water-cement ratio, adding silica fume and fly ash, and replacing coarse aggregates by fine aggregates [47][48][49][50], to see if incorporating CNT can further improve the fatigue performance of ultra-high performance cementitious composites that already has compact cementitious matrix and densified interfacial transition zone. Additionally, the fatigue fracture surface morphology of cementitious composites without/with CNT was compared to investigate the effect of CNT on the fatigue cracking characteristics at nano/micro-scale in cementitious matrix and interfacial transition zone. ...
The compressive fatigue performance of cementitious composites largely depends on the generation and connection of fatigue nano/micro-cracks in the composites. These types of cracks are beyond the scope that traditional fibers can restrain, but can be effectively eliminated and inhibited by incorporating nano-materials, especially those with fiber shape, such as carbon nanotube (CNT). Unfortunately, the effect of CNT and its physical and chemical characteristics on the compressive fatigue performance of cementitious composites remains unclear. Therefore, this paper systematically investigated the effect of CNT with different contents and sizes, functional groups and coating layers on the compressive fatigue performance of cementitious composites, including fatigue life, strength, deformation behavior and cracking characteristics. The morphology of the fatigue fracture surface of cementitious composites shows that CNT can refine pore structure, bridge nano/micro-cracks and result in the generation of the multi-directional and network-like fatigue micro-cracks as well as the appearance of the fatigue striation around aggregates. Consequently, by increasing the integrity among each phase of cementitious composites, CNT significantly maximizes the compressive fatigue life (in logarithmic form), strength and failure strain of cementitious composites by 160%, 43.4% and 20.6%, respectively, showing great potential for extending the service life of concrete structures.
Cracking, mainly referring to fatigue damage, is one of the primary distress modes of asphalt pavement. The inquiry into the fatigue resistance of asphalt binders and mixtures are summarized in this paper, along with the affecting factors, the fatigue resistance correlations between binders and mixtures, and improved measurement. The influencing factors of fatigue performance for recycled asphalt pavement are divided into intrinsic, such as Reclaimed Asphalt Pavement (RAP) content, types of asphalt binder, and aggregate gradation, and external, such as rejuvenator, mixed additives, and temperature. The different fatigue evaluation methods and indices of binder and mixtures significantly affect the fatigue resistance correlations between binders and mixtures. The various binder properties and fatigue test conditions in binders and mixtures can cause a remarkable change in the fatigue performance correlations. Furthermore, adding softer virgin asphalt, rejuvenator, warm mixing agent, and optimizing the gradation of recycled mixtures are utilized to meet the fatigue behavior requirement in the engineering practice. From the perspective of the fatigue behavior of asphalt materials, this work provides light on the design of materials for environmentally friendly and long-life pavement, and recommends areas for future investigation that are pertinent to fatigue resistance of recycled asphalt pavement.
Pavement Deflections and Fatigue Failures
- F N Hveem
Hveem, F. N. Pavement Deflections and Fatigue Failures. Bulletin 114, HRB, National Research Council, Washington, D.C., 1955.
Asphalt Mixture Behavior in Repeated Flexure
- C L Monismith
- J A Epps
- D A Kasianchuk
- D B Mclean
Monismith, C. L., J. A. Epps, D. A. Kasianchuk, and D. B. McLean. Asphalt Mixture Behavior in Repeated Flexure. Report TE 70-5. University of California, Berkeley, 1971.
Asphalt Pave-ment Design—The Shell Method
- A I M Claessen
- J M Edwards
- P Sommer
- P Ugé
Claessen, A. I. M., J. M. Edwards, P. Sommer, and P. Ugé. Asphalt Pave-ment Design—The Shell Method. Proc., 4th International Conference on Structural Design of Asphalt Pavements, Ann Arbor, 1977.
Moni-smith. Sensitivity of SHRP-A003A Testing Equipment To Mix Design Parameters for Permanent Deformation and Fatigue
- J B Sousa
- A A Tayebali
- J T Harvey
- P Hendricks
Sousa, J. B., A. A. Tayebali, J. T. Harvey, P. Hendricks, and C. L. Moni-smith. Sensitivity of SHRP-A003A Testing Equipment To Mix Design Parameters for Permanent Deformation and Fatigue. In Transportation Research Record 1384, TRB, National Research Council, Washington, D.C., 1993.