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Influence of durability properties on performance of bitumen stabilised materialsTwagira, Elias Mathaniya 03 1900 (has links)
Thesis (PhD (Civil Engineering))--University of Stellenbosch, 2010. / ENGLISH ABSTRACT: In both developing and developed countries, to ensure sustained economic growth the quest for
optimal roads performance is an extremely high priority. A global increase in the use of foamed
bitumen and bitumen emulsion materials (BSMs) as a solution to roads maintenance,
rehabilitation, and upgrading has become evident. This is driven by environmental policies
aimed at conserving energy and limiting the exploitation of new borrows pits. It has therefore
become imperative that BSMs are used optimally, and, in order to achieve this, practitioners
need to understand the mechanisms that influence durability and long-term performance.
The changes in the behaviour of materials and the failure mechanisms of BSM mixes
are long-term phenomena. This implies that the study of the physicochemical and mechanical
properties of the mixes is vital. Therefore, a fundamental understanding of the moisture damage
and age-hardening characteristics, which are related to materials’ properties, is required. The
main objective of this study is to advance BSM technology by assessing the influence of the
selected materials on durability behaviour and long-term performance in all phases of
application (i.e. mix design, construction, and in-service condition).
This study begins with a comprehensive literature review of research dealing with the
interactions of binder and mineral aggregates. The properties of bitumen (foamed bitumen or
bitumen emulsion) and mineral aggregates were reviewed. This was followed by review into the
colloidal behaviour of foam and emulsion and physicochemical and mechanical interaction with
mineral aggregates. Factors influencing the interaction of BSMs were then identified. Finally, the
fundamental theories on thermodynamics, hydrodynamics, and electrokinetics were used to
describe the step-by-step process by which adhesive bonding and cohesion occur in BSMs.
The mixture durability in terms of moisture damage was investigated. To achieve this
aim, the physical and mechanical moisture-induced damage process was analysed. The test
control parameters were established and a laboratory device to quantify these parameters
designed. New moisture conditioning procedures were developed and demonstrated in this
study. From the moisture induction simulation test (MIST) procedure, it became evident that
pulsing water pressures into compacted and cured BSM mixes simulates the hydrodynamic
effect that occurs in the field due to dynamic traffic loading. The different mix matrices typically
applicable to the recycling processes – such as Hornfels-RAP and Quartzite crushed stone,
stabilised with either foamed bitumen or bitumen emulsion and the addition of active filler
(cement or lime) – were investigated. It was found that a new moisture-conditioning procedure
using the MIST device and monotonic triaxial testing can distinguish those BSM mixes that are
resistant to moisture damage from those that are less resistant. The validation of the MIST and
monotonic test results was done using the APT device, which is the MMLS3 wet trafficking test.
The results on both tests showed good correlations in evaluating and screening BSMs in terms
of moisture susceptibility.
Field temperature data was collected and a model to accurately simulate the curing of
BSMs was identified and proposed for further investigation and validation. It was found from the
field temperature data collected in this study that the temperature gradient on the study site
varied according to the depth of the BSMs (that is, 10oC-17oC during winter and 17oC– 47oC
during summer). Understanding the influence of the temperature conductivity and rate of
evaporation is important for inferring moisture damage and age-hardening behaviour and proper
selection of BSMs.
The age-hardening behaviour of BSMs is linked to the durability properties and longterm
performance of these materials. The fundamental characteristics associated with shortand
long-term age hardening were investigated in this study. The short-term dimension involved
assessing the age-hardening characteristics of the binder (foamed bitumen colloids and bitumen emulsion droplets) prior to the production of BSMs. The long-term study involved extracting and
recovering the binder from the briquettes (made from different mixes) compacted in the
laboratory and cores extracted from different field pavement sections which were in service for
8-10 years. The study found that the length of time bitumen is kept in circulation in the
laboratory plant at elevated temperature (170oC–180oC) before making BSM-foam contributes
to the ageing of the binder, especially after eight hours. The foaming process in itself was found
not to alter the bitumen properties. It is recommended that a temperature range between 160oC-
165oC be used for the production of foamed bitumen with softer bitumen. This will not
compromise its quality. In addition, the time of circulation of bitumen in laboratory plant should
not be longer than three (3) hours.
The rheological properties of the bitumen recovered from laboratory briquettes and cores
from field pavement show that age hardening on foamed bitumen and bitumen emulsion during
in-service life occurred. The ageing also seemed to be dependent on the effect of traffic, with
trafficked areas (i.e. on-wheel path and inner-wheel path) experiencing more ageing than untrafficked
areas (i.e. between-wheel path). However, the extraction and recovery process was
found to be complex, and produce uncertain results. Although the results show that binders in
BSMs undergo age hardening, its distinct behaviour in BSM performance was not obvious from
the extensive tests carried out in this study.
The last part of the study contains its conclusions and recommendations. The study
provides an insight into fundamental material durability properties, and this will assist in
improving the current procedure for selection, combining and formulation of the mix matrices for
BSMs. In addition, the study provides guidelines that will enable practitioners to confidently
apply a mix that is durable and long-lasting. The specific durability-related issues addressed in
this study are substance for future research. This novel solution to the application of BSMs will
benefit all parties involved in the development of pavement recycling technology. / AFRIKAANSE OPSOMMING: Om volgehoue ekonomiese groei te verseker in beide ontwikkelende en ontwikkelde lande,
geniet die soeke na die optimale werkverrigting van paaie ’n baie hoë prioriteit. ‘n Wêreldwye
toename in die gebruik van skuimbitumen en bitumen-emulsiemateriale (BSMs) as ’n oplossing
vir padonderhoud, rehabilitasie en opgradering is merkbaar. Dit word meegebring deur die
omgewingsbeleide wat die ontginning van nuwe leengroewe beperk en besparing van energie
bevorder. Die korrekte gebruik van hierdie materiale vereis dat die meganismes wat die
duursaamheid en langtermyn-werkverrigting daarvan beïnvloed, deeglik verstaan word.
Die verandering in materiaalgedrag en falingsmeganismes van BSM materiale is
langtermynverskynsels. Dit impliseer dat bestudering van die fisiochemiese en meganiese
eienskappe van die mengsels uiters belangrik is. Dis dus voor die hand liggend hoe belangrik
vogbeskadiging en verharding met tyd, wat verwant is aan materiaaleienskappe, is. Die
hoofdoelwit met hierdie studie is om die vooruitgang van BSM tegnologie te versnel deur dit
moontlik te maak om gekose materiale te evalueer op grond van hulle invloed op duursaamheid
en langtermyn-werkverrigting in alle toepassingsfases (naamlik mengontwerp, konstruksie en
dienstoestand).
Hierdie studie begin met ’n uitgebreide literatuuroorsig oor fundamentele begrippe van
die karakterisering van interaksie van die bindstof en die minerale-aggregate. Inligting oor
bitumen (skuimbitumen en bitumen emulsies) en eienskappe van minerale aggregate is
bestudeer. Dit is gevolg deur ’n studie van die fundamentele begrip van die kolloïdale gedrag
van skuim en emulsie, asook fisiochemiese en meganiese interaksie met minerale aggregate.
Faktore wat die interaksie van BSM-materiale beïnvloed is geïdentifiseer. Die basiese teorie
van termodinamika, hidrodinamika en elektrokinetika is daarna gebruik om stap vir stap die
proses en formulering van adhesie-binding en kohesie in die BSMs, wat in hierdie studie
aangebied word, te beskryf.
Die kwantifisering van mengsel-duursaamheid in terme van vogbeskadiging is ontwikkel.
Om hierdie doel te bereik, is die fisiese en meganiese proses van beskadiging deur
vogindringing geïdentifiseer. Die gekontroleerde parameters is bepaal en ’n
laboratoriumapparaat is ontwerp om hierdie parameters te kwantifiseer. Nuwe
vogkondisioneringsprosedures is ontwikkel en in hierdie studie gedemonstreer. Van prosedures
van voggeïnduseerde sensitiwiteitstoetsing (Engels: moisture induction simulation test (MIST))
was dit duidelik dat pulsering van waterdruk in BSM materiale die hidrodinamiese effek naboots
wat in die veld bestaan as gevolg van dinamiese verkeerslaste. Verskillende mengselmatrikse
wat tipies is van hergebruik, soos byvoorbeeld hoornfels-hersikleerde asfalt produk (Engels:
recycled asphalt product (RAP)) en vergruisde granietklip, met skuimbitumen of bitumenemulsie
gestabiliseer en met byvoeging van aktiewe vulmateriaal (sement of kalksteen), is
ondersoek. Daar is bevind dat nuwe vogkondisioneringsprosedures (soos bepaal deur MIST
apparaat en drie-assige toets) kan onderskei tussen BSM materiale wat weerstandig is teen
vogbeskadiging en dié wat minder weerstandig (vatbaar) is. Die geldigheid van die MIST en
monotone toetsresultate is bepaal deur gebruik van die APT apparaat wat ’n MMLS3 nat
verkeerstoets is. Die resultate van beide toetse toon goeie korrelasie in die keuring van BM
materiale in terme van vogvatbaarheid.
In hierdie ondersoek is veldtemperatuurdata versamel en die toepaslike model om
verouderende BM lae akkuraat te simuleer is geïdentifiseer en voorgelê vir verdere ondersoek
en verifikasie. Daar is uit veldtemperatuurdata bevind dat temperatuurgradiënt op die betrokke
terrein gewissel het met die dikte van die BSM, naamlik 10oC-17oC gedurende die winter en
17oC-47oC gedurende die somer. Begrip vir die invloed van temperatuuroordragkoëffisiënt en
verdampingstempo is belangrik by die afleiding van vogbeskadiging en verharding met
ouderdom en die korrekte keuse van BSM materiale.Verouderingsverhardinggedrag van BSMs is verwant aan die duursaamheidseienskappe en
langtermynwerkverrigting van hierdie materiale. Die basiese karakteristieke wat met kort- en
langtermyn verouderingsverharding geassosieer word, is in hierdie studie ondersoek. Die klem
op die kort termyn is geplaas op die verouderingsverhardingsgedrag van die bindstof
(skuimbitumen kolloïdes en bitumen-emulsiedruppels) voordat BSMs vervaardig word. In die
lang termyn evaluasie het die studie ekstraksie en herwinning van bindstof uit brikette wat in die
laboratorium gekompakteer is (van verskillende mengsels) en uit kerns verkry vanaf verskeie
plaveiselgedeeltes na 8-10 jaar diens ingesluit. Die ondersoek het bevind dat die tydsverloop
waarin bitumen in sirkulasie gehou is by verhoogde temperatuur (170oC-180oC) in die
laboratorium-aanleg voordat BSMs vervaardig is, veral indien na 8 uur, bydra tot die
veroudering van die bindstof. Die skuimproses op sigself verander nie die bitumeneienskappe
nie. Daar word aanbeveel dat temperature tussen die grense 160oC-165oC gehandhaaf word
vir produksie van skuimbitumen met sagter bitumen sonder dat die kwaliteit benadeel word en
dat die sirkulasietyd nie 2 tot 3 ure behoort te oorskry nie.
Die reologiese eienskappe van die herwinde bitumen vanuit laboratoriumbrikette en
kerns van plaveisels toon dat ouderdomsverharding van skuimbitumen en bitumen-emulsie
tydens die diensleeftyd plaasvind. Die veroudering is skynbaar ook afhanklik van
verkeerseffekte, met belaste areas (in wielspoor of binne wielspoor) wat ’n hoër mate van
veroudering toon as onbelaste areas (tussen wielspore). Die ekstraksie- en herwinningsproses
op sigself was egter bevind as baie kompleks met uiters onseker resultate. Dit het gelei tot
onsekere gedrag in terme van ouderdomsverharding van die BSM bindmiddel (skuim of
emulsie). Alhoewel resultate toon dat die bindmiddels ouderdomsverharding ondergaan het, is
die BSM werkverrigting nie duidelik uit die uitgebreide toetse wat in hierdie studie uitgevoer is
nie.
Die laaste deel van die studie bevat gevolgtrekkings en aanbevelings. Die studie lewer
insig in die fundamentele duursaamheidseienskappe van die materiaal, wat bydra tot
verbetering van die huidige prosedure van seleksie, saamstelling en formulering van die
mengmatriks vir BSMs. Verder voorsien dit ’n metode wat in die praktyk gebruik kan word om
met vertroue duursame mengsels met lang diensbaarheidsleeftye te vervaardig. ’n Nuwe
oplossing en vooruitgang in die toepassing van BSMs is daargestel tot voordeel van alle partye
betrokke by die ontwikkeling van herwinningstegnologie.
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Characterization of Recycled Concrete for use as Pavement Base MaterialBlankenagel, Brandon J. 20 August 2005 (has links) (PDF)
The use of recycled concrete material (RCM) as pavement base material is a promising but unproven technique for road rehabilitation and construction. A telephone survey conducted to investigate the state of the practice concerning RCM usage in Utah County revealed that RCM is infrequently used in this application due primarily to a lack of practical knowledge about the engineering properties of the material. Therefore, this research was aimed at evaluating the physical properties, strength parameters, and durability characteristics of both demolition and haul-back sources of RCM available in Utah County for use as pavement base material. The study included extensive laboratory and field testing. Laboratory tests included California bearing ratio (CBR), unconfined compressive strength (UCS), stiffness, freeze-thaw cycling, moisture susceptibility, abrasion, salinity, and alkalinity evaluations. Non-destructive testing was utilized in the field to monitor seasonal variation in stiffness of an RCM pavement base layer over a 1-year period. The testing included a dynamic cone penetrometer, ground-penetrating radar, a heavy Clegg impact soil tester, a soil stiffness gauge, and a portable falling-weight deflectometer. The laboratory testing indicated that the demolition material exhibited lower strength and stiffness than the haul-back material and reduced UCS loss after freeze-thaw cycling. However, the demolition material received a moisture susceptibility rating of good in the tube suction test, while the haul-back material was rated as marginal. Both materials exhibited self-cementing effects that led to approximately 180 percent increases in UCS over a 7-day curing period. Seven-day UCS values were 1260 kPa and 1820 kPa for the demolition and haul-back materials, respectively, and corresponding CBR values were 22 and 55. The field monitoring demonstrated that the RCM base layer was susceptible to stiffness changes due primarily to changes in moisture. In its saturated state during spring testing, the site experienced CBR and stiffness losses of up to 60 percent compared to summer-time values. RCM compares well with typical pavement base materials in many respects. Given the laboratory and field data developed in this research, engineers should be able to estimate the strength and durability parameters of RCM needed for pavement design.
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Efeitos da cal hidratada e do ácido polifosfórico nas propriedades mecânicas e suscetibilidade à umidade de misturas asfálticas densas / Effects of hydrated lime and polyphosforic acid in mechanical properties and moisture susceptibility in dense asphalt mixturesGrande, Wilson Ricardo de 06 June 2011 (has links)
Esta pesquisa teve por objetivo analisar os efeitos da cal hidratada e do ácido polifosfórico nas propriedades mecânicas e suscetibilidade à umidade de misturas asfálticas densas. O ligante utilizado foi o CAP 50/70, chamado de controle, modificado com 0,6 e 1,2% de PPA, e como aditivo a cal hidratada em concentrações de 1,5 e 3,0%, perfazendo nove combinações de misturas asfálticas. Foram moldados 108 corpos-de-prova, divididos em 4 e 7% de volume de vazios, sendo que os corpos-de-prova de 7% foram divididos em condicionados e não condicionados. Os ensaios realizados para análise das propriedades mecânicas foram o Módulo de Resiliência e a Resistência à Tração Indireta. Os resultados mostram que o aumento da concentração de ácido polifosfórico melhora a rigidez e a flexibilidade, e melhora a suscebilidade ao dano por umidade, assim como aumenta a resistência à tração; para a cal hidratada, com o aumento da sua concentração, ocorreu aumento da rigidez e da flexibilidade de maneira mais discreta, se comparado ao ácido polifosfórico, e proporciona a diminuição da resistência à tração: o teor que apresentou melhor suscetibilidade ao dano por umidade foi de 1,5% de cal hidratada. / This work aims to analyze the effects of hydrated lime and polyphosphoric acid on the mechanical properties and moisture susceptibility of dense asphalt mixtures. In nine combinations of asphalt mixtures, CAP 50/70, named control and modified with 0,6 and 1,2% of PPA, was employed as binder, and hydrated lime in concentrations of 1,5 and 3,0% was used as additive. 108 test specimens have been molded and divided into 4 and 7% of volume void, considering that 7% were separated into conditioned and non-conditioned. The Resilient Modulus and the Tensile Strength were the tests conducted for the analysis of mechanical properties. The results showed that the increase in polyphosphoric acid concentration improved stiffness and flexibility and increased the susceptibility to moisture damage, as well as the tensile strength. Also in the results, with the concentration increase of the hydrated lime, there was a smaller increase of stiffness and flexibility, and it provided a decrease of tensile strength, considering that the percentage of 1,5% of hydrated lime presented the best susceptibility to moisture damage.
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Efeitos da cal hidratada e do ácido polifosfórico nas propriedades mecânicas e suscetibilidade à umidade de misturas asfálticas densas / Effects of hydrated lime and polyphosforic acid in mechanical properties and moisture susceptibility in dense asphalt mixturesWilson Ricardo de Grande 06 June 2011 (has links)
Esta pesquisa teve por objetivo analisar os efeitos da cal hidratada e do ácido polifosfórico nas propriedades mecânicas e suscetibilidade à umidade de misturas asfálticas densas. O ligante utilizado foi o CAP 50/70, chamado de controle, modificado com 0,6 e 1,2% de PPA, e como aditivo a cal hidratada em concentrações de 1,5 e 3,0%, perfazendo nove combinações de misturas asfálticas. Foram moldados 108 corpos-de-prova, divididos em 4 e 7% de volume de vazios, sendo que os corpos-de-prova de 7% foram divididos em condicionados e não condicionados. Os ensaios realizados para análise das propriedades mecânicas foram o Módulo de Resiliência e a Resistência à Tração Indireta. Os resultados mostram que o aumento da concentração de ácido polifosfórico melhora a rigidez e a flexibilidade, e melhora a suscebilidade ao dano por umidade, assim como aumenta a resistência à tração; para a cal hidratada, com o aumento da sua concentração, ocorreu aumento da rigidez e da flexibilidade de maneira mais discreta, se comparado ao ácido polifosfórico, e proporciona a diminuição da resistência à tração: o teor que apresentou melhor suscetibilidade ao dano por umidade foi de 1,5% de cal hidratada. / This work aims to analyze the effects of hydrated lime and polyphosphoric acid on the mechanical properties and moisture susceptibility of dense asphalt mixtures. In nine combinations of asphalt mixtures, CAP 50/70, named control and modified with 0,6 and 1,2% of PPA, was employed as binder, and hydrated lime in concentrations of 1,5 and 3,0% was used as additive. 108 test specimens have been molded and divided into 4 and 7% of volume void, considering that 7% were separated into conditioned and non-conditioned. The Resilient Modulus and the Tensile Strength were the tests conducted for the analysis of mechanical properties. The results showed that the increase in polyphosphoric acid concentration improved stiffness and flexibility and increased the susceptibility to moisture damage, as well as the tensile strength. Also in the results, with the concentration increase of the hydrated lime, there was a smaller increase of stiffness and flexibility, and it provided a decrease of tensile strength, considering that the percentage of 1,5% of hydrated lime presented the best susceptibility to moisture damage.
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Etude physico-chimique des possibilités de valorisation des sables argileux non conformes dans des mélanges bitumineux routiers / A mineralogical approach to use the non-qualified fine aggregates in asphalt concrete pavementChen, Chi-Wei 29 March 2016 (has links)
Ma thèse de doctorat doit contribuer à la diminution du gaspillage des ressources naturelles (en particuliers les sables naturels) en étendant leur acceptabilité dans les enrobés bitumineux. La compréhension de l’effet des particules nocives, notamment la fraction argileuse contenue dans les sables, sur le comportement des mélanges bitumineux est visé. Pour évaluer le niveau de nocivité des particules fines, le test d'adsorption du bleu de méthylène noté MB (EN13043, NF EN 933-9) est appliqué, mais un tel test a été modifié à quatre reprises au cours des 22 dernières années tandis que la valeur de bleu limite, utilisée pour déterminer la conformité ou non du sable, n’a pas été modifiée. Le projet de thèse vise à modifier cette valeur limite pour étendre la gamme de sable utilisable. Cet objectif sera atteint grâce à l’identification de la composition minéralogique des sables, une recherche sur la meilleure manière de quantifier les phases qui composent les sables et une meilleure compréhension du rôle de la fraction fine sur la durabilité et les pathologies des mélanges bitumineux. Le travail de thèse est organisé en différentes tâches : 1. Tester le protocole de mesure de la valeur de bleu. Nous voulons comprendre l'effet de différents facteurs (tels que l'échantillonnage, la cinétique des additions de bleu, la température de séchage du sable avant l’essai ...) sur la mesure de la valeur de bleu. Le développement d'un appareil automatique ou d'une nouvelle méthode (qui sera validée par comparaison avec les résultats obtenus à partir de la méthode standardisée) est prévu.2. Établir une corrélation entre la valeur de bleu (ou d'autres paramètres à trouver) et la quantité de phases minérales présentes dans les sables. Un jeu de données a d’ores et déjà été établi au cours de mon stage de master. Pour atteindre cet objectif, les différentes méthodes de quantification (utilisant en particuliers la diffraction de rayons X) doivent être testées et comparées.3. Corréler la valeur de bleu couplée à la nature minéralogique des particules fines avec le comportement mécanique des mélanges sable/bitume. Nous allons étudier la dégradation en présence d’eau des propriétés du matériau bitumineux (par exemple l'adhésion du liant bitumineux sur granulat) et le rôle de la couche de particules fines qui entourent les grains de sable sur les propriétés mécaniques de ce matériau. Nous espérons comprendre en particulier l'effet de la présence d’argile gonflante dans les matériaux constitutifs de la chaussée bitumineuse.4. Améliorer le comportement des granulats non conformes par l’application d’un traitement. Après l'identification de l'origine des pathologies (nous faisons l'hypothèse que les argiles gonflantes jouent un rôle majeur), nous proposons d'appliquer un traitement en ajoutant de la chaux (ou de traiter en ajoutant des déchets qui contiendraient des substances actives comme la chaux), et de tester également l’utilisation de polymères ou du greffage avec des composés organiques des argiles comme traitement / Siliceous fines (clays) in fine aggregates used for AC pavement stimulate the moisture entering the bitumen-aggregates interface in AC mixture and create channels for water penetration. MB adsorption for qualifying fine aggregates is in accordance with the layer charge and the accessibility of consisted mineralogy in fine aggregates. However, the correlation between MB qualification for fine aggregates and fine aggregates triggering moisture susceptibility of AC mixture has not ever been addressed; moreover, the questions from MB adsorption still remain to be solved. In order to evaluate the stripping and to clarify MB adsorption on fine aggregates from a mineralogical perspective, the most common clays in natural aggregates, kaolinite, illite and montmorillonite, were extracted from their clay rocks, and used to prepare thin clay film, artificial fine aggregates and asphalt concrete mixtures consist of artificial fine aggregates. Moreover, the 5 blinded fine aggregates received from quarries without any given information were applied as the blinded experiments to confirm the practicability with mineralogical diversity. The mineralogical analysis was identifying and quantifying the mineral phases in extracted clay and fine aggregates by using X-Ray diffraction, and the quantitative results were judged by complementary test. MB adsorption was studied using drop method, UV-Photometer method and cation exchange capacity from clays and aggregates. Water-bitumen-clay interaction was studied using the sessile drop and the Oliensis spot tests on those thin clay films. The water intrusion routes in AC mixture was investigated immersing AC mixture in solution with chemical probe, whereas Duriez tests allowed measuring the moisture susceptibility of AC mixtures containing varied clay mineralogy in fine aggregates. The results show that clay mineralogy is in relation to water-bitumen-clay interaction, and it is agreed by moisture susceptibility of AC mixture indicated by Duriez test. With the dispersive nature bitumen used in this study, cohesive failure is in the light of kaolinite-AC mixture in the presence of water, whereas swelling property is responsible for the stripping in illite- and montmorillonite- AC mixture. In order to exclude the physical interferences on MB adsorption, the vale of 100% of MB adsorption on fine aggregates referred to CEC value is necessary to apply, and MB value measured from drop method efficiently excludes the significant impacts from layer charge, pH value and exchangeable cations. Although MB adsorption is in relation to clay mineralogy, this test does not sufficiently indicate the stripping of AC mixture occurred by clay in fine aggregates. There are still rooms to use the non-qualified fine aggregates for the use of AC pavement. As Rietveld method from X-Ray diffraction derives the most reasonable quantitative results, the X-Ray powder diffraction and the X-Ray orientated EG treated K-saturated clay diffraction are proposed for analyzing clay mineralogy and its swelling property for judging the use of non-qualified fine aggregates for AC mixture.MB2 and Duriez0.8 surfaces can be established on clay mineralogical map since we discovered MB adsorption and moisture susceptibility are related to clay mineralogy in fine aggregates. The fine aggregates which is not qualified by MB adsorption is going to confirm the possibility for the use of AC pavement by the mineralogical analysis through X-Ray diffraction. By adopting the quantitative results of clay on mineralogical map with Duriez0.8 surface and the swelling property of clays in fine aggregates, the use of fine aggregates for AC pavement can be properly judged according to water-bitumen-aggregates interaction and stripping which has been proved in this study
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