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Introduction. The causes of premature destruction of asphalt concrete coatings are aging and low quality of bitumen. The paper describes the methods for improving the bitumen properties. The authors present the review of the bitumen modification by carbon black usage. The usage of carbon black leads to structural changes in the bitumen. Therefore, the authors select carbon black additives as a promising modifiers.Materials and methods. The paper showed the characteristics of carbon modifiers and the properties of the initial bitumen.Results. The authors experimentally determined the main parameters of the modified bitumen and compared the effect of three carbon black additives on the bitumen properties. The usage of activated carbon black significantly reduced the penetration of bitumen than non-activated carbon black, however, the indicators of aging were declined.Discussion and conclusions. As a result, the solid additive’s usage increases the bitumen viscosity with other standard characteristics’ preservation, and thus improves the bitumen thermal stability. Therefore, the usage of activated carbon black in dry forms does not affect significantly on the bitumen properties in comparison with varietal N 375 grade-carbon.

Petroleum products consist mainly of aliphatics, aromatics, asphaltenes and resins. After oil exploitation, the concentrations of asphaltenes and resins are high in oil reservoirs; however, they are also the petroleum pollutants most recalcitrant to degradation, leading to high oil viscosity. A sizable amount of work has been dedicated to understand the degradation mechanisms of aliphatics and aromatics; however, in comparison, little work has been carried out on asphaltene and resin degradation. This review discusses our current knowledge on the understanding of asphaltene and resin degradation. More specifically, it sheds light on work carried out to date on the degradation of these pollutants, and highlights the major gaps that limit our understanding of their degradation pathways. It also presents new potential research areas that can be explored to fill in these gaps.

This study reports the recovery of bitumen concentrate from Ondo tar sand by alkaline leaching stripping of the associated sand. Bitumen was extracted from the tar sand as received in un-stirred and stirred state in the oven and on the magnetic stirrer hotplate, respectively, at varying 32 factorial design combinations of temperature and sodium hydroxide molar concentrations at 40 g/dm3 pulp density. The tar sand was further subjected to bitumen dissolution test and recovery of bitumen at varying pulp density. The results obtained showed that bitumen was optimally stripped from the tar sand with initial bitumen content of about 34% in the stirred condition to produce a concentrate with grade and recovery percents of 98.82 and 99.41% of bitumen, respectively. The optimal leaching stripping was obtained at 2 M sodium hydroxide concentration, at 90 °C temperature and 25 minutes contact time. The ultra-clean bitumen obtained can serve as raw material input for petroleum products recovery and as a coking additive in blend formulation of coals for metallurgical coke making.

Lignin is an abundant biopolymer with potential value-added applications that depend on biomass source and fractioning method. This work explores the use as emulsifiers of three native lignin-rich product coming from industrial bioethanol production and alkali or Kraft pulping. In addition to their distinctive characteristics, the different molecular organization induced by emulsification pH is expected to interact in various ways at the water-oil interface of the emulsion droplets. Initially, model oil-in-water (O/W) emulsions of a silicone oil will be studied as a function of lignin source, disperse phase concentration and emulsification pH. Once stablished the effect of such variables, emulsion formulations of three potential bitumen rejuvenators (waste vegetable cooking oil, recycled lubricating oil and a 160/220 penetration range soft bitumen). Droplet size distribution, Z-potential and viscous tests conducted on model emulsions have shown that emulsification pH strongly affects stabilization ability of the lignins tested. Regarding bitumen rejuvenators, lignin emulsification capability will be affected by surfactant source, pH and, additionally, by the dispersed phase characteristics. Lower Z-potential values shown by KL at pH 9 and 11 seem to facilitate emulsification of the less polar disperse phases formed by RLUB and bitumen. In any case, lower particle size and higher yield stress values were found for both bioethanol-derived lignins emulsifying RVO and RLUB at pH 13, which are expected to exhibit a longer stability

This study presents an investigation into the improvement of strength and durability properties of lateritic soil blocks using Millet Husk Ash (MHA) and Bitumen as additives so as to reduce its high cost and find alternative disposal method for agricultural waste. The lateritic soil samples were selected and treated with 0%, 10%, 15%, 20%, 30%, 40% and 50% of MHA by weight of laterite. The lateritic soil-MHA mixture was later admixed with 0%, 2%, 4%, 6%, 8%, 10%, 12% and 14% cut-back bitumen solution by weight of laterite. Both the natural lateritic soil, lateritic and MHA, and the blend of Soil, MHA and Bitumen were first subjected to physical and chemical analysis using X-Ray Fluorescence (XRF) and Scanning Electromagnetic Machine (SEM) to determine their engineering properties followed by the performance test on bricks cast with varying quantities of the additives. A total of one hundred and ninety two (192) cubes were tested for moisture absorption, erodability and compressive strength tests. The result of the test showed that MHA and Bitumen acted as pozzolana in performance test on the soil blocks. Up to 30% MHA – laterite and 20% MHA admixed with 8% laterite were found to give optimum compressive strength of 10.8N/mm 2 and 10.9N/mm 2 for the bricks produced. The result also showed that about 50% MHA blended with 14% Bitumen solution ensured water tight bricks. Thus the use of MHA as partial replacement of cement will provide an economic use of by-product and consequently produce a cheaper soil block construction without comprising its strength. Keywords: Millet husk, ash, bitumen, soil block, mechanical properties, compressive strength

The aim of this research was to characterize and analyze the formulation of emulsified modification bitumen (EMB) as well as the industrial wastes used in the formulation. Bitumen being a non-renewable product with severe environmental issues arising lately led to the use of industrial wastes such as plastic and recycled base oil in this research. Physical characteristic studies were performed to analyze the decomposition temperature, boiling point, flash point, density, moisture content, element content in waste plastics, and flowability of bitumen emulsion. Eight ratios of modified bitumen were formulated and compared with the industrial grade bitumen. The modified bitumen with a penetration value of 103 mm and softening value at 49 °C was chosen for the emulsification process where three emulsifiers were added into the mixture of bitumen and water. These samples were compared with the industrial bitumen emulsion. From the analysis, the formulated emulsion was obtained from a mixture consists of 20% bitumen, 7% polymer, and 73% recycled base oil.

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The global road network spans 64.3million km and is of huge significance for the social and economic development. The level of investment in road construction and maintenance is high, e.g. EU €44billion/year (2019), China €614.7billion/year (2019) and US €94billion/year (2019). Despite the level of investment, there has been minimal investment in the development of new asphalt technologies, particularly when compared with R&D investment in other industries, such as the automotive industry. Despite the limited investment, there have been some innovations in asphalt technology. For the past 20 years, researchers have developed bio-inspired asphalt technology, self-healing and bio-binders and have applied them to asphalt pavements. This research has emerged as a response to global warming and the need to reduce both carbon emissions and reliance on oil in asphalt technology. This paper charts the development of two bio-inspired technologies and considers their significance in relation to the need to reduce carbon emissions and oil dependence (in line with the UN strategic goals, specifically: SDG 9, 11 and 12). This paper considers the potential benefits of bio-inspired technologies and outlines the current barriers to their further development. This paper aims to begin a conversation with stakeholders on how to speed up the acceptance of bio-inspired asphalt technologies and their adoption in road design, construction and maintenance. Or is it the case that we have reached the end of the road for bio-inspired road construction materials?

The main purpose of this paper is to present the development of a new predictive model intended for the calculation of stiffness modulus |E*| determined by a four-point bending beam test (4PBB or 4PB-PR). The model developed, called model A, was based on the Witczak model, which was developed for the dynamic-modulus (DM) method. Most of the asphalt mixtures used to develop the model were high-modulus asphalt concrete (HMAC). The most commonly used methods for determining the stiffness modulus |E*| of asphalt mixtures were also discussed. The paper presents the results of the study for 10 asphalt mixtures but 8 of them were used to develop the predictive model. In addition, the results of complex shear modulus G* tests on neat and modified bituminous binders carried out in a dynamic shear rheometer (DSR), necessary for the development of a predictive model, are presented. The tests carried out in the dynamic shear rheometer had significant measurement uncertainties. The results of the volumetric parameters of the asphalt mixtures are also reported. The developed model A has maximum absolute errors e = 1930 MPa (p = 95%) and maximum relative errors re = 50% (p = 95%). The distribution of the absolute errors of the model, after discarding outliers, has a normal distribution as in the development of other models of this type, which was confirmed by appropriate statistical tests. On the basis of the tests and calculations carried out, it was concluded that, in order to increase the precision of the predictive models, it is advisable to reduce the measurement uncertainty of the bitumen complex shear modulus G*. For the developed model A, the limiting values of the stiffness modulus |E*| are also shown, within which the determined stiffness modulus should fall.

Η παρούσα εργασία αναλύει τον τρόπο με τον οποίο διαμορφώνεται ο ανταγωνισμός σε εξειδικευμένες ναυτιλιακές αγορές. Η μελέτη του ανταγωνισμού είναι θεμελιώδης για την επιχειρηματική απόδοση σε κάθε κλάδο. Στην παρούσα εργασία ορίζονται οι εξειδικευμένες αγορές και παρουσιάζονται παραδείγματα από τη ναυτιλιακή βιομηχανία. Εξετάζεται ο στρατηγικός σχεδιασμός των ναυτιλιακών εταιρειών και αξιολογούνται οι ανταγωνιστικές στρατηγικές που διαμορφώνονται από τις εταιρείες διαχείρισης πλοίων. Εξετάζεται η μελέτη περίπτωσης μιας εξειδικευμένης αγοράς στη ναυτιλιακή βιομηχανία, η αυτή της μεταφοράς της ασφάλτου, στην περιοχή της Μεσογείου και της Μαύρης Θάλασσας. Η υπάρχουσα βιβλιογραφία σχετικά με τον ανταγωνισμό των επιχειρήσεων, το εξειδικευμένο (niche) εμπόριο και ειδικότερα για ναυτιλιακές στρατηγικές, μελετήθηκε διεξοδικά και διενεργήθηκε μελέτη περίπτωσης για την αγορά ασφάλτου. Η ανάλυση αποδεικνύει ότι το εξειδικευμένο μάρκετινγκ είναι επωφελές για τις περισσότερες ναυτιλιακές αγορές μικρής κλίμακας. Ο προσδιορισμός του ανταγωνιστικού πλεονεκτήματος της επιχείρησης καθώς και η χρήση συνδυασμού ανταγωνιστικών στρατηγικών συνεπάγονται ισχυρή θέση στην αγορά. Τα ευρήματα δείχνουν ότι η αγορά της ασφάλτου αποτελεί παράδειγμα εξειδικευμένης αγοράς, με διακριτά χαρακτηριστικά. Οι εταιρείες που δραστηριοποιούνται σε αυτή την αγορά είναι παρούσες και σε άλλες ναυτιλιακές αγορές υγρού φορτίου ή μικρών αποστάσεων. Η έρευνα υποστηρίζει ότι ο ανταγωνισμός διαμορφώνεται κυρίως μέσω της στρατηγικής εστίασης στο κόστος και δευτερευόντως μέσω της διαφοροποίησης., This paper analyzes the way competition is shaped in niche shipping markets. Studying the competition is fundamental for business performance in every industry. In this paper, niche markets are defined and examples from the shipping industry are demonstrated. The strategic planning of shipping companies is examined and the competitive strategies that are formed by ship management companies, are evaluated. A case study of one niche market in the shipping industry, the transportation of bitumen in the Mediterranean and the Black Sea, is tested. Existing literature on business competition, niche marketing, and shipping strategies, in particular, was critically reviewed and a case study was conducted for the bitumen market. The analysis argues that niche marketing is beneficial for most small scaled shipping markets. Determining the company’s competitive advantage and using consolidated competitive strategies imply a strong market position. The findings indicate that the bitumen market is a demonstration of a niche market, with distinct characteristics. Companies involved in this market are present in other wet cargo or short-sea shipping markets. The inquiry claims that competition is formed primarily through cost focus strategy and secondarily through differentiation.

Hot water extraction of bitumen from Alberta oil sands generates large quantities of tailings slurry. The fine grained sludge component of this waste is the most troublesome because of its stability and poor compaction potential. Dispersed bitumen, and organic matter that is insoluble in common solvents (IOM), are associated with the fines contained in these clay slimes. This organic matter is believed to be partly responsible for the intractability of the sludge, and it could therefore play an important role in determining the behavioural characteristics of oil sands slimes. In this investigation the settling behaviour of the sludge was studied after removal of emulsified bitumen by an oil phase agglomeration technique. After partial removal of bitumen the sludge was fractionated into settling and non-settling fractions. The insoluble organic matter associated with the clay lines present in the non-settling portion of sludge was concentrated by dissolving the mineral matter in HCl/HF. These fractions were analysed using elemental analysis and solid state ¹³C n.m.r. spectroscopy. The elemental analyses were discussed in terms of a van Krevelen diagram by plotting H/C atomic ratios against O/C atomic ratios. N.m.r. data were used to calculate the aromaticities of the various organic fractions. Based on the n.m.r. data, it is suggested that the IOM associated with sludge solids is derived from the parent oil sand feed.

Roads, due to use and time, become aged and as a result, they require maintenance. This paper presents a promising technology to compensate ageing. The method uses porous aggregates as capsules containing rejuvenator. The rejuvenator will be released during the asphalt pavement's service life, reversing the impact of ageing on asphalt performance, properties and, thus, extending pavement's durability. This paper describes the properties of two porous aggregates, the encapsulation method and the properties of the capsules. The capsules were incorporated into an asphalt mix and their fundamental properties analysed. Finally, the recovery potential of the aged binder was evaluated using ageing tests. The results demonstrate the effectiveness of the technology, a change in binder properties was observed over time, but to a lesser extent for the bitumen when capsules were included than for the reference. The solution also highlights the benefits of using encapsulated rejuvenator over the use of rejuvenator directly added to the mix. The authors acknowledge the financial support from the National project REPARA v2.0, funded by the Centre for Industrial Technological Development (CDTI) of the Spanish Government within the programme supporting the Strategic National Consortiums for Technical Investigation (CIEN). The authors wish to thank Mr. Carlos Martín-Portugués Montoliu and Mr. Francisco José Lucas Ochoa from ACCIONA and REPSOL, respectively, for their contribution to this study. Similarly, we are grateful to Professor Juan Gallego Medina from the Polytechnic University of Madrid, for his collaboration in the development of the research.

This paper attempts to display, analyze and discuss the literature affiliated to the previous research data on road surfacing in pavement engineering reinforcement. In this paper, a review of the background and present status of road surfacing is also provided for supportive explanation of the significance of fiber-reinforced asphalt pavement HMA and its role in providing effective and durable surfacing for heavy-trafficked roads. The paper attempts to clarify some of the terms and notions related to the discussions to give the readers the needed background, to be able to actively understand the experiments and discussions. Results from many studies confirm that fiber specifically enhances the optimum bitumen content in the design of the mixture and halts the bitumen leakage due to its asphalt absorbing susceptibility. Fiber modifies the visco-elastic response, susceptibility against moisture, increase resistance to rutting, as well as lowers the pavement fatigue cracking.

The reduction in the ability of bitumen to bond with the aggregate surface due to the infiltration of moisture has been recognised for years, and this deterioration phenomenon is called moisture damage. In general, the loss of bonding between bitumen and aggregate shortens the service life of the top layer of the pavement. Many investigations have been conducted to understand the mechanisms of moisture damage due to the loss of bonding strength between bitumen and aggregate and to find ways to improve and strengthen the bond to mitigate the effect of moisture. This paper reviews the extensive literature on the loss of bitumen-aggregate bonding strength due to moisture damage in asphalt mixtures. The general description of the theories and mechanisms that explain the effect of the thermodynamic, chemical, physical and mechanical characteristics of the bitumen and aggregate on the bonding phenomenon are discussed in this paper. In addition, the causes of and contributing factors to moisture damage and methods to improve the bond between bitumen and aggregates are also discussed. Moreover, a description of the test methods that can be used to evaluate moisture damage in poorly bonded and compacted mixtures are also presented. Special attention is given to a well-known method, known as the pull-off test, which has been successfully used to evaluate aggregate-binder bond strength, both for laboratory and in-situ tests. This includes the test methods, the factors that affect the bonding strength results and their correlation with other test method. A review of the failure mode of bitumen under the pull-off loading test is discussed in the final section of this paper.

The global increase of road infrastructure and its impact on the environment requires serious attention to develop sustainable and environmentally friendly road materials. One group of those materials is produced by using bitumen emulsion. However, there are still scientific and technical obstacles standing against its regular application. The bitumen emulsion formulation process and compositional optimization are subjected to a high number of degrees of freedom. Consequently, obtaining the desired product is mostly based on a series of random and tedious trials because of the enormous number of tests to be carried out. The current review of the physicochemical formulation may indeed be extensively used in helping to reduce the number of unnecessary experimentations as well as discuss the vital aspects in the bitumen emulsion production process. Among these, emulsion stability, viscosity, droplet size (and distribution), bitumen emulsion chemistry, the function of the emulsion components, surfactant type, acids or alkalis, and additives are all discussed and used to define the emulsion's physical properties and reactivity. Besides, current developments in the mechanisms of breaking and setting processes are also summarized. It is discussed how emulsions are graded based on their reactivity, particle charge, and physical features. Two emulsification techniques are outlined namely the colloid mill method and the High Internal Phase Ratio (HIPR) method. Furthermore, some emulsion formulation tools/theories were identified and are explained. In that way, optimized formulations can be used to offer a practical guide for bitumen emulsion manufacturers when trying to formulate a well-defined bitumen emulsion for its use in pavement infrastructure rather than simply to meet standard specifications. This review paper aims to enable the ultimate potential of the bitumen emulsion in the field of cold recycling technology by further following up the research progress of bitumen emulsion manufacturing, therefore, this paper reviews and discusses the literature available up to now on this topic, in road engineering and emulsion chemistry.

Práce se zabývá korelací výsledků nízkoteplotních zkoušek asfaltových směsí s výsledky nízkoteplotních zkoušek nejčastěji používaných asfaltových pojiv. Vlastnosti používaných materiálů v teplotách, které se s měnícím klimatem stále častěji přibližují kritickým hodnotám, jsou stále více aktuálním tématem, které nesmí být opomínáno. Snahou této práce je poukázat na míru v jaké je možné ovlivnit tyto vlastnosti pomocí různých pojiv. Pro tento účel byly provedeny zkoušky, kterými jsou mimo jiné určení kritické teploty zkouškou nízkoteplotních vlastností s rovnoměrným řízeným poklesem teploty (TSRST), kritického bodu lámavosti dle Fraase a průhybového trámečkového reometru. The paper deals with results of tests for low temperature properties of asphalt mixtures in correlation with results of tests on low temperature properties of the bitumen used in those. Properties of materials used in temperatures, which with changing climate keep approaching the critical value, are still very current topic, which cannot be overlooked. The aim of this paper is to point out the extent in which we can affect these properties with different binders. For this purpose, low temperature tests were carried out which include the thermal stress restrained specimen test to set critical temperature of asphalt mixture, Fraasse breaking point and the bending beam rheometer.

The failure of bituminous pavements takes place due to heavy traffic loads and weather-related conditions, such as moisture, temperature, and UV radiation. To overcome or minimize such failures, a great effort has been put in recent years to enhance the material properties of bitumen, ultimately improving field performance and increasing the pavement service life. Polymer modification is considered one of the most suitable and by far the most popular approach. Elastomers, chemically functionalised thermoplastics and plastomers * (* Note: notwithstanding the fact that in Polymer Science the word ‘plastomer’ indicates a polymer with the simultaneous behaviour of an elastomer and plastics (thermoplastics), this paper uses the term ‘plastomer’ to indicate a thermoplastic polymer as it is more commonly found in Civil and Pavement Engineering.) are the most commonly used polymers for bitumen modification. Plastomers provide several advantages and are commonly acknowledged to improve high-temperature stiffness, although some of them are more prone to phase separation and consequent storage instability. Nowadays, due to the recent push for recycling, many road authorities are looking at the use of recycled plastics in roads. Hence, some of the available plastomers—in pellet, flakes, or powder form—are coming from materials recycling facilities rather than chemical companies. This review article describes the details of using plastomers as bitumen modifiers—with a specific focus on recycled plastics—and how these can potentially be used to enhance bitumen performance and the road durability. Chemical modifiers for improving the compatibility between plastomers and bitumen are also addressed in this review. Plastomers, either individual or in combination of two or three polymers, are found to offer great stiffness at high temperature. Different polymers including HDPE, LDPE, LLDPE, MDPE, PP, PS, PET, EMA, and EVA have been successfully employed for bitumen modification. However, each of them has its own merit and demerit as thoroughly discussed in the paper. The recent push in using recycled materials in roads has brought new light to the use of virgin and recycled plastomers for bitumen modification as a low-cost and somehow environmental beneficial solution for roads and pavements.

This paper introduces the maximum and minimum pavement temperatures of Estonian asphalt pavements in accordance with calculation models developed for North America and Norway. Historical meteorological data from 1992 to 2021 obtained from 25 different weather stations in Estonia were used as an input for the respective models. Comparison between the calculation models demonstrated high variability of the pavement design temperatures, thus significantly impacting the bitumen grade selection. Based on the road weather stations data, the Norwegian and Canadian models provide the most accurate pavement temperature estimations for Estonian conditions. Calculated upper and lower-bound pavement design temperatures varied between +52 °C to +58 °C and −22 °C to −34 °C, respectively. All models showed milder pavement temperatures and lower seasonal temperature amplitudes for coastal and offshore areas. The results also indicated the importance of validating model suitability as well as correlation with actual pavement temperatures in the Baltic region.

Although archaeological excavations have recovered a large number of vessels used to hold perfumes or ointments in ancient Rome, little is known about the chemical composition or origin of the substances they contained. Most available information pertains to ointment and/or cosmetic bases rather than to essences. The discovery in 2019 of an ointment jar (unguentarium) made of rock crystal (quartz) that was sealed with a stopper and contained a solid mass in a Roman tomb in Carmona (Seville, Spain) was a rather unusual finding. This paper reports the results of an archaeometric study of the unguentarium stopper and its contents. Based on them, and on comparisons with commercially available patchouli and nard oil standards, the perfume held in the unguentarium was probably patchouli. To our knowledge, this may be the first time a perfume from Roman times has been identified, which is a major advance in this field. The unguentarium stopper consisted of dolomite, a material also unknown in this type of use, and bitumen was used to seal the unguentarium with the stopper.

This paper reviews effect of wax content to performance of bitumen and asphalt pavement. Negative influence of wax content is known from literature reviews, which effects elasticity of binder and causes sensitivity to low temperatures and increases cracking. There is lack information of methods to evaluate wax content in bitumen. This paper presents literature review of variety of wax types, separation wax as saturated hydrocarbons by studying fractional composition and methodology for determination of wax content in bitumen and negatively effect of crystallization. Article in Lithuanian. Vaško kiekio poveikio bitumo ir asfalto dangos funkcionavimui teorinis tyrimas Santrauka Šiame straipsnyje aprašomas vaško kiekio poveikio bitumo ir asfalto dangos funkcionavimui teorinis tyrimas. Iš teorijos yra žinomas neigiamas vaško kiekis, turintis įtakos bitumo elastingumui, kuris lemia jautrumą žemai temperatūrai bei didina trapumą. Tačiau Lietuvoje bei kitose Europos valstybėse stokojama patirties taikant vaško kiekio bitume įvertinimo metodus. Tuo tikslu atlikta mokslinė literatūros analizė siekiant nustatyti vaško bitume rūšis, vaško kaip dalies sočiųjų angliavandenilių išskyrimą, tiriant bitumo komponentinę sudėtį, ir metodus, taikytinus vaško kiekiui bitume bei neigiamam kristalizavimosi poveikiui ištirti. Reikšminiai žodžiai: asfalto danga, bitumas, kristalizavimasis, vaškas.

Littering waste is among the top environmental issues in the world, and the management of the waste has turned into a challenge in almost every city. It has been reported that 75% of smokers dispose of their cigarette butts (CBs) on the ground, even in public places. Researchers have discovered that CBs make up more than one-third of the total littered waste on the planet. Cigarette butts predominantly consist of a cellulose acetate fiber (plastic)-based filter wrapped in paper. Waste CBs contain burnt tobacco and tar, along with many other toxic chemicals. They take years to biodegrade depending on the environmental conditions, and toxic chemicals leach out and contaminate the environment. As part of an ongoing project, this paper presents a novel and sustainable technique to recycle cigarette butts in bitumen for the construction of flexible pavements. In this research, CBs have been pre-processed and mixed with bitumen classes C320, C170, and PMB A10E as a fiber modifier. Comprehensive laboratory investigations, including a penetration test, softening point test, and viscosity test, have been performed along with a binder drain off test to evaluate the performance of the modified samples. During this investigation, samples were prepared with 0.3% cellulose fiber, 0.2%, 0.3% 0.4%, and 0.5% CBs. The results of the CB-modified samples were compared with the sample with cellulose fiber and fresh bitumen (0% fiber). The results show that the physical and rheological properties of bitumen incorporating CBs improve significantly, and CBs could be used instead of virgin cellulose fiber as a fiber modifier.

The asphalt industry’s incentive to reduce greenhouse gas emissions has increased since the 1990s due to growing concerns on environmental issues such as global warming and carbon footprint. This has stimulated the introduction of Warm Mix Asphalt (WMA) and its technologies which serve the purpose of reducing greenhouse gas emissions by reducing the mixing and compaction temperatures of asphalt mix. WMA gained popularity due to the environmental benefit it offers without compromising the properties, performance and quality of the asphalt mix. WMA is produced at significantly lower temperatures (slightly above 100 °C) and thus results in less energy consumption, fewer emissions, reduced ageing, lower mixing and compaction temperatures, cool weather paving and better workability of the mix. The latter of these benefits is attributed to the incorporation of additives into WMA. These additives can also confer even better performance of WMA in comparison to conventional Hot Mix Asphalt (HMA) methods. Even though there are recommended dosages of several WMA additives, there is no general standardized mixture design procedure and this makes it challenging to characterize the mechanism(s) of action of these additives in the warm mix. The effects of the addition of additives into WMA are known to a reasonable extent but not so much is known about the underlying interactions and phenomena which bring about the mechanism(s) by which these additives confer beneficial features into the warm mix. Additives in a certain way are being used to bridge the gap and minimize or even nullify the effect of the mixing temperature deficit involved in WMA processes while improving the general properties of the mix. This review presents WMA technologies such as wax, chemical additives and foaming processes and the mechanisms by which they function to confer desired characteristics and improve the durability of the mix. Hybrid techniques are also briefly mentioned in this paper in addition to a detailed description of the specific modes of action of popular WMA technologies such as Sasobit, Evotherm and Advera. This paper highlights the environmental and technical advantages of WMA over the conventional HMA methods and also comprehensively analyzes the mechanism(s) of action of additives in conferring desirable characteristics on WMA, which ultimately improves its durability.

Kruja zone represents mainly shallow-water carbonate deposits (Cr2-Pg2). They consist of dolomites, limestones with rudists also rich in miliolides and textularides with frequent hiatus, emersions, discontinuity surfaces and even bauxitic horizons. This paper aid to provide some explanations about the origin of blue clays within paleokarst infillings, caverns and the presence of bitumen and their impact in the surrounding rocks in the region of Burizana in Makareshi anticline structure, Kruja zone. This area was previously known for oil exploration and several exploration wells were drilled, in the South-East, as Makareshi-1 well, while in the West, Ishem, a series of wells, all with the object of oil exploration in carbonate section from the surrounding structures. Also, in this region, the presence of Miocene transgression is present. The presence of terrigenous rocks in the highest hypsometric position, the intrusion of blue-grey clays between carbonate formation, the smell of sulphur in the blue clay formation and the bitumen signs in the cavities of the carbonate rocks are part of the present study.

Crumb rubber modified bitumen (CRMB) has excellent high-temperature performance and fatigue resistance, and is widely used in asphalt pavement to cope with increasing traffic axle load and changing climate. Under conventional preparation conditions, the swelling degree of CR can directly impact the comprehensive properties of CRMB; however, physical and chemical properties research on swelling crumb rubber (SCR) and crumb rubber recycled bitumen (CRRB) in CRMB is relatively lacking. In this paper, the working performance of CRMB and CRRB in high-temperature and low-temperature conditions were studied through physical and working performance testing of bitumen. The CR and SCR were tested by scanning electron microscope (SEM), Fourier transform infrared spectrometer (FTIR), gel permeation chromatography (GPC), and particle size distribution (PSD) tests to study the physicochemical behavior and microscopic effects before and after CR swelling. The results showed that CR dosage was in the range of 10%, 15%, and 20%, as well as that CR dosages have a positive effect on the high- and low-temperature performance, storage stability, and elastic recovery of bitumen. The high-temperature PG grades of bitumen were directly improved by four grades, and the elastic recovery rate increased by 339.9%. CR improved the ultra-low temperature crack resistance of bitumen. Due to the absorption of lighter components by CR, the relative content of the heavy component of bitumen increased; however, its low-temperature performance decreased significantly. After swelling, the CR particle size increased and the range became wider, the surface complexity of CR became higher, and the specific surface area was larger. At the same time, CR carried out the transformation process from large and medium molecules to small molecules. During the swelling process, a new benzene ring structure appeared in the CR, and the C–C bond and C–S bond of CR broke, forming part of the C=C bond.

An adequate moisture resistance is a key element to guarantee the durability of asphalt materials. This paper identifies the influence of filler typology and bitumen content on the mechanical response of asphalt mortars before and after water action. Two fillers were evaluated: Portland cement and Calcium carbonate, along with different contents of a penetration bitumen (B35/50). Stiffness, ductility, and fatigue were evaluated through a new protocol for asphalt mortar samples using a 3-point-bending test on DMA (Dynamic Mechanical Analyzer). The use of Portland cement presents higher stiffness, lower ductility, and improved fatigue and water resistance compared to Calcium carbonate. It is also possible to optimize bitumen content based on fatigue results. Content beyond the optimal reduce variations after water action but compromise fatigue resistance. Lower content leads to a poorer performance in both terms. This methodology enables asphalt mortar characterisation as a tool to optimise the design of asphalt materials., La influencia del tipo de polvo mineral y contenido de ligante bituminoso en la resistencia a la humedad y fatiga de morteros bituminosos. La resistencia al agua es clave para garantizar la durabilidad de los materiales asfálticos. Este estudio identifica la influencia del polvo mineral y contenido de betún en la respuesta mecánica de morteros bituminosos antes y después de la humedad. Se evaluaron dos tipos de filler: cemento Portland y carbonato cálcico (filler calizo), junto con distintos contenidos de betún (B35/50). Rigidez, ductilidad y fatiga fueron evaluados mediante un nuevo ensayo de fatiga a tres puntos para morteros empleando DMA (Dynamic Mechanical Analyzer). El cemento presenta más rigidez, menos ductilidad y mayor resistencia al agua y fatiga que el filler calizo. Los resultados de fatiga permiten además optimizar el contenido de betún. Contenidos por encima del óptimo reducen variaciones tras la humedad pero comprometen la resistencia a fatiga. Contenidos menores conllevan un peor comportamiento en ambos términos. Esta metodología permite usar la caracterización de morteros bituminosos para optimizar el diseño de materiales asfálticos.

In recent years, the research on bitumen has reached the nanometer level, but there are still some problems in the study of the relationship between the atomic force microscope (AFM) nano-morphology and ageing of bitumen. The purpose of this paper is to find out the effect of thermal oxygen ageing on the nano-morphology of bitumen. Atomic force microscope (AFM) test sample of bitumen was prepared in this paper. Area ratio of bee-like structure, roughness, and maximum amplitude were selected as the nano-morphological parameters of the bitumen. The calculation method of nano-parameters was also proposed. Bitumen with different ageing degrees was prepared by thin film oven test (TFOT). Nano-morphological parameters of bitumen with different ageing degrees were obtained by AFM and analyzed with NanoScope Analysis, and the relationships between nano-morphological parameters and bitumen technical indexes after ageing, such as penetration, ductility, softening point, and viscosity were analyzed. The test results show that the wave crests and wave troughs of the bee-like structure on the surface of the bitumen alternate, while the other areas are relatively flat. The bee-like structure continues to develop as the ageing time prolongs, and the number of bee-like structures decreases, but the volume and the undulation degree increase. With the ageing time prolonging, the nano-parameters of bitumen, such as the area ratio of bee-like structure, roughness, and maximum amplitude, show a trend of increasing gradually, but the increasing rates become smaller and smaller. During the ageing process of bitumen, with the increase of nano-morphological parameters (area ratio of bee-like structure, roughness, and maximum amplitude), penetration at 25 &deg, C and ductility at 15 &deg, C of the bitumen decrease, and softening point and viscosity at 60 &deg, C increase. AFM testing technology and image analysis method in this paper can be used for a reference in the nano-scale study of bitumen.

This paper employs the linear viscoelastic parameter G '/tan delta as the quantitative criterion for identifying a common relationship with the Ring and Ball softening point of both unmodified and polymer-modified bitumen (PMB). Temperature sweep was conducted at 10 rad/s with dynamic shear rheometer to determine the complex shear modulus G* and phase angle delta of bitumen. The parameter G '/tan delta could be obtained. Logarithmic interpolation was applied for G '/tan delta to determine the equivalent softening temperature T-s (_G '/tan delta ) at which G '/tan delta equals the proposed criterion values. With this method, a good agreement could be reached between T-s (_G '/tan delta ) and the softening point for both unmodified bitumen and PMB. While keeping high accuracy for unmodified bitumen, the accuracy of T-s (_G '/tan delta ) as an estimation of the softening point of PMB was largely improved when compared to the iso-modulus approach. The reliability of this quantitative relationship is preliminarily verified and its implementation is discussed in the Black space.

Asphalt is a common material that is used extensively for roadways. Furthermore, bituminous mixes have been used in railways, both as asphalt and as mortar. Different agencies and research institutes have investigated and suggested various applications. These studies indicate the benefits of bituminous material under railways, such as improving a substructure’s stiffness and bearing capacity; enhancing its dynamic characteristics and response, especially under high-speed train loads; waterproofing the subgrade; protecting the top layers against fine contamination. These potential applications can improve the overall track structure performance and lead to minimizing settlement under heavy loads. They can also guarantee an appropriate response under high-speed loads, especially in comparison to a rigid slab track. This review paper documents the literature related to the utilization of asphalt and bituminous mixes in railway tracks. This paper presents a critical review of the research in the application of asphalt and bituminous mixes in railway tracks. Additionally, this paper reviews the design and construction recommendations and procedures for asphalt and bituminous mixes in railway tracks as practiced in different countries. This paper also provides case studies of projects where asphalt and bituminous mixes have been utilized in railway tracks. It is anticipated that this review paper will facilitate (1) the exchange of ideas and innovations in the area of the design and construction of railway tracks and (2) the development of unified standards for the design and construction of railway tracks with asphalt and bituminous mixtures.

Cracks are one of the most widespread modes of deterioration of asphalt concrete road pavements in Ukraine. The main cause of cracking in asphalt pavements is tensile stress due to loads from vehicles as well as abrupt temperature decease and its significant gradients in winter. Observations indicate that joint influence of the above-mentioned factors results in cracking in relatively thin asphalt overlays (5 to 10 cm), placed on existing pavement surface with cracks in wearing course, during the first year of performance. Most extensively cracks appear in spring and autumn, and open in winter. Cracks have different length, width and depth. At high temperatures in summer period “young” minor cracks can partly be rolled by wheels of vehicles at wheel path due to bitumen softening in asphalt concrete. Practice of repair works shows that crack sealing at early stage of their initiation allows us to avoid premature pavement deterioration and increase its service life. Particular significance has crack sealing prior to beginning of precipitations in autumn as moisture penetration in pavement layers through cracks in surface layer and then in subgrade soil accelerates premature deterioration of the whole structure. In severely continental climate of Ukraine surface of asphalt pavements in summer can have a temperature up to 60 – 65 °C, and up to minus 30 °C in winter, which requires from materials for crack sealing special properties as heat resistance and flexibility at low temperatures. In Ukraine sealing of cracks with polymer modified bitumen sealants and hot applied mastics in asphalt pavements is applied, allowing block access of moisture to lower pavement layers and increase its durability. Petroleum road bitumen, modified with plasticizer, is used as base for production of bitumen-polymer sealants. Combination of plasticized bitumen and SBS-type polymer, and cationic polymer latex allows to obtain sealant characterized by both high elasticity, flexibility at low temperatures and heat resistance. Addition of mineral filler to the composition of bitumen-polymer sealant gives us bitumen-polymer mastic. Results of research of different filler influence on heat resistance, elasticity, flexibility and performance of polymer modified mastics at low temperatures have been highlighted in the paper. Influence of temperature of asphalt pavement on strength of adhesive interaction with polymer modified mastic has been determined. Experience of practical implementation of techniques of crack sealing in asphalt pavements on motor road network in Ukraine indicates that technique of filling of beforehand prepared “reservoir” with hot bitumen-polymer sealant or mastic with overband on the surface of asphalt pavement results in the highest impermeability of crack, compared to flush filling of “reservoir”. To increase durability it is important that the “reservoir” created by milling of asphalt pavement had square or rectangular cross-section and passed through crack. Technological sides of practical implementation of techniques of crack sealing in asphalt pavements are covered in the paper.

The final publication is available at Springer via http://dx.doi.org/10.1617/s11527-022-01936-6 This paper discusses the analysis of uniaxial tension–compression cyclic strain sweep test results for the characterisation of bituminous materials. The test results of one bitumen and two mastics, at different oxidative ageing levels, at three different temperatures are used in the study. The damage mechanisms leading to failure were shown to vary with the temperature, and the transition from slow to fast damage accumulation could be clearly seen in the evolution plots of different mechanical variables with loading cycles. It was shown that the plot of test results in the Black diagram provides an excellent viewpoint for the damage and non-damage related mechanisms affecting the material’s response to increasing loading amplitude. Before significant damage has accumulated in the specimen, the stiffness modulus-phase angle curve, at different temperatures, follows very closely the linear viscoelastic curve of the undamaged material, and heating was identified as the most important reversible mechanism. The thixotropic effect was clearly observed in mastics. The curve shape during fast progression to failure was related to the level of deformation around the crack zone. The slope of the stiffness modulus-phase angle curve was found to provide a consistent indicator of the material’s resistance to cumulative loading, as it is sensitive to the material’s ageing state and the test temperature, and a unique relationship between this factor and the number of cycles to failure was found for all materials and test conditions.

The paper discusses the effect of the amount and particle size of rubber on the properties of rubber-modified bitumen. Therefore, rubber-modified bitumen with rubber contents of 10, 15 and 20 % and a variation of the particle size from small (0.4 mm) to middle (0.8 mm) and up to big (1.0 mm) were prepared in laboratory by using a paving bitumen 50/70 as reference bitumen. Additionally, a polymer-modified bitumen (PmB 25/55-55), which is commonly used in asphalt wearing and binder courses, was involved in the investigations to verify the modification states. Different laboratory tests were conducted to evaluate the influence of the selected rubber particles. At first, the impact of the rubber modifications on conventional bitumen tests are presented. Furthermore, DSR tests were conducted to determine performance related bitumen properties. DSR results have also been used to determine the rutting susceptibility. In addition, the binders were rated to their fatigue damage resistance by applying repeated load cycles using the DSR test device as well. Following, the paper gives recommendations in terms of the use of rubber-modified binders for asphalt pavements.

Damage in pavements is known to reduce over time when the material is left to rest, this phenomenon is identified as healing. It has been shown that healing has a large influence on pavement performance. However, as the healing mechanism is not fully understood, there is currently no accepted method available to assess the healing performance of an asphalt binder. Healing of cracks can be seen as the sum of two processes, cracked surfaces coming into contact (wetting) and strength gain of the contact area (intrinsic healing). This paper aims to increase the understanding of the process of two surfaces coming into contact. Healing of bitumen is assessed using a novel test method, which allows for controlled variation of the stress state during healing. This method consists of bringing two pieces of bitumen together and allowing them to heal under controlled conditions. The extent of healing is then assessed by testing the healed specimens in direct tension. The results, presented in this paper, show that the stress state at assembly and during healing has a significant impact on the extent of healing.

Moisture in bitumen and at the bitumen-aggregate interface affects the cohesive and adhesive properties of asphalt mixtures, which are critical for the service performance and durability of pavements. This paper aims to investigate the kinetics and thermodynamics of moisture transport in bitumen at various temperatures and relative humidity for different bitumen types. Transport models are introduced to study the moisture transport mechanisms. A parameter optimization approach combined with the finite element method is applied to simulate moisture transport behavior. Results show salient sorption increase at higher relative humidity levels (more than 70%), indicating the occurrence of clustering of water molecules in bitumen, which can lead to a significant decrease of the diffusion coefficient. Transport models show great quality in simulating experimental results, in which the S-Cluster model provides a detailed explanation of the moisture transport mechanisms and describes better the performance at high sorption levels. The diffusion coefficient, cluster size and activation energy were determined and were found to be linked to the bitumen chemical and structural properties. The transport kinetics and thermodynamics are expected to contribute to a comprehensive understanding of moisture transport behavior in bitumen and further of pavement moisture damage at complex and interacting environmental conditions.

Road degradation is an increasing problem for assets managers. Roads deteriorate mainly due to the combination of different factors, such as temperature, climate and traffic loads. This causes the asphalt to age and, consequently, the bituminous mixtures become more fragile and microcracks begin to appear. To eliminate these degradation effects, the most widely used performed actions are based on the renovation of the pavement to achieve an asphalt surface under acceptable conditions of use. In order to reduce the application of corrective measures when the asphalt pavement is already facing significant defects, it is important to perform regular preventive maintenance that minimise the renovation works of the pavement and improves the asphalt durability. This paper shows a method for the continuous rejuvenation of asphalt, by analysing the evolution of asphalt mixture stiffness and the resistance to cracking on asphalt mixtures with rejuvenator added after having been submitted to a laboratory ageing protocol (short and long-term ageing). The rejuvenator was added to the mixtures following either of these two procedures: first, directly added to the mixture and the second, saturated in porous aggregates, what the authors call encapsulated. Results from this study demonstrate the effectiveness of the second method (encapsulated rejuvenator) as an original solution to achieve long-term performance mixtures with reduced cracking. The authors acknowledge the financial support from a National project, REPARA v2.0, funded by the Centre for Industrial Technological Development (CDTI) of the Spanish Government within the programme supporting the Strategic National Consortiums for Technical Investigation (CIEN).

This paper investigates the properties of waste plastic film and carbon nanotubes modified asphalt mixes. The composed asphalt mixes have been evaluated for fatigue cracking and rutting. In this research, a total of 30 numbers of samples were prepared with different percentages of waste plastic films and carbon nanotubes from 0.1 to 0.4% and evaluated for dynamic stability and rutting using the wheel tracking machine. Results show that the addition of carbon nanotubes significantly increases the dynamic stability of asphalt and decreases the rutting up to a sufficient level as compared to plastic and conventional bitumen.

Nach den aktuellen Regierungsprogrammen, soll Österreich bis zum Jahr 2040 klimaneutral werden. Klimaneutralität bedeutet, dass insgesamt weniger CO2 emittiert als aufgenommen bzw. gebunden werden kann. Vor diesem Hintergrund ist vor allem die Baubranche gefordert, Maßnahmen für mehr Nachhaltigkeit zu treffen, um die CO2-Emissionen in Zukunft zu reduzieren und die nationalen und internationalen Klimaziele zu erreichen. Die Asphaltproduktion als Teilbereich der Baubranche steht somit ebenfalls vor der Herausforderung, ihre CO2-Emissionen zu reduzieren und ein Bewusstsein für den Klimaschutz zu schaffen. Die gegenständliche Arbeit beschäftigt sich mit der Untersuchung und Analyse von Maßnahmen zur Reduktion der CO2-Emissionen bei der Asphaltproduktion. Ziel ist es, die Nachhaltigkeitspotentiale bei der Asphaltproduktion aufzuzeigen und unterschiedliche Maßnahmen zu untersuchen, mit welchen der Ausstoß von Treibhausgasen bei der Asphaltproduktion verringert werden kann. Einleitend werden die Randbedingungen der Untersuchungen erläutert sowie die Systemgrenzen festgelegt. Anschließend wird auf den Baustoff Asphalt, die Asphaltproduktion sowie auf die aktuellen Normen und Richtlinien im Zusammenhang mit der Asphaltproduktion eingegangen. Im zweiten Teil der Arbeit wird die Umweltwirkung der konventionellen Asphaltproduktion ermittelt. Auf Basis der gewonnenen Daten wurden folgende Maßnahmen untersucht, um die CO2-Emissionen bei der konventionellen Asphaltproduktion zu reduzieren: - Zugabe von Asphaltrecycling - Reduktion der Feuchtigkeit des Gesteins - Art des Energieträgers - Auslastung der Asphaltmischanlage Abschließend findet sich eine Darstellung der Ergebnisse mit Schlussfolgerung auf Basis der vorangegangenen Untersuchungen. According to the current government programmes, Austria is to become climate neutral by 2040. Climate neutrality means that in total less CO2 is emitted than can be absorbed or bound. Against this background, the construction industry in particular is called upon to take measures for more sustainability in order to reduce CO2 emissions in the future and to achieve the national and international climate targets. Asphalt production, as a sub-sector of the construction industry, is thus also faced with the challenge of reducing its CO2 emissions and creating awareness for climate protection. This study deals with the investigation and analysis of measures to reduce CO2 emissions in asphalt production. The aim is to show the sustainability potentials in asphalt production and to examine different measures with which the emission of greenhouse gases in asphalt production can be reduced. At the beginning, the boundary conditions of the investigations are explained and the system boundaries are defined. Then, the building material asphalt, asphalt production and the current standards and guidelines with regard asphalt production are discussed. In the second part of the paper, the environmental impact of conventional asphalt production is determined. Based on the data obtained, the following measures were investigated to reduce CO2 emissions in conventional asphalt production: - Addition of asphalt recycling - Reduction of the moisture content of the aggregate - Type of energy source - Utilisation of the asphalt mixing plant Finally, there is a presentation of the results with a conclusion based on the previous investigations. Abweichender Titel laut Übersetzung der Verfasserin/des Verfassers Masterarbeit Wien, FH Campus Wien 2022

The ageing of bitumen has received great attention both from a chemical and rheological perspective due to its direct impact on asphalt performance. However, open questions with respect to the convergence of the synchronous ageing changes in rheology and chemistry of bitumen still exist. This paper addresses these alterations of chemistry and rheology and attempts to establish a link via fitting rheological equations fed by fundamental chemical information. To that end, three binders of different type were used in four different laboratory ageing states. A number of spectroscopic techniques and rheological testing were employed to derive corresponding chemical and rheological parameters. In parallel, various statistical methods (Bivariate analysis, Wilcoxon test, Factor analysis) assisted in identifying relationships among the chemo-rheological parameters and simplifying the number of variables. The results of this study demonstrate that chemistry and rheology are following similar changes when considering laboratory ageing following the fast-rate phase of a dual oxidation scheme and short-term lab ageing. Finally, this work manages to establish a linking framework for a number of newly-introduced rheological parameters. All in all, the results of this study might be particularly interesting for future interventions in the chemical composition of bitumen, considering its effect on performance.

The use of solar energy to partially satisfy the demand for heat in the bitumen industry constitutes an enormous step towards industrial decarbonization. This paper investigates the effect of thermal fluctuations caused by solar energy usage in bitumen storage in the region of Rabat, Morocco. We studied different temperature ranges and storage periods, covering the most common scenarios in this region. This work inspected the impact of these studied conditions on the performance of 35/50 bitumen. After the simulation of fluctuations through thermal storage, we simulated short-term and long-term aging using RTFO and PAV tests, respectively. In addition to the needle penetration at 25 °C and the determination of softening point tests, we used a dynamic shear rheometer (DSR) and Fourier-transform infrared spectroscopy (FTIR) to assess the rheological and chemical evolutions of the samples. We found that thermal fluctuations enhanced the rheological performance of the binders by improving their rutting and fatigue cracking resistance. We observed that longer storage durations (three months) under thermal fluctuations made bitumen more prone to oxidation in the long term. We conclude that solar energy usage in bitumen storage is not detrimental as long as we avoid long storage periods (more than one month), especially when the maximum storage temperature is higher than 165 °C.

This paper studies the possibility of minimizing energy consumption during 35/50 bitumen storage. Similarly to most bitumen companies, the company with which we collaborated uses fossil fuel to maintain bitumen tanks at 150 °C. The main objective is to optimize energy usage. To achieve this purpose, we tested two new storage processes. One is based on dynamic temperature storage between 140 and 160 °C, and the other on room temperature conditions. This work evaluates the effect of these storage conditions on the quality of 35/50 bitumen, and studies the energy aspect to calculate the energy profit for every storage method. After storage, we have studied short-term and long-term ageing using the Rolling Thin Film Oven (RTFOT) and the Pressure Ageing Vessel (PAV) tests, respectively. We characterized the samples using needle penetration at 25 °C, the softening point, and Attenuated Total Reflectance-Fourier Transform Infrared (ATR-FTIR) spectroscopy. We observed that the change in physical properties is negligible after the tested storage processes. Chemically, both the storage conditions affected the oxidative behavior acceptably, the carbonyl index was the same in the long term. We conclude that we can store 35/50 bitumen at room temperature conditions, which follow us to save more than three times the energy needs compared to the standard configurations.

In this paper, a conventional road bitumen with penetration grade 100–130 is compounded with tar in order to obtain bitumen with improved low temperature resistance. The low temperature (at −24 °C, −30 °C and −36 °C) resistance of the virgin bitumen and the compounded one is evaluated by testing on a bending beam rheometer. It was found that the optimum compounding (20% of tar by weight) decreases the stiffness essentially (from 18% to 34%), i.e., it increases the low temperature resistance of the bitumen. The stiffness decreases in the compounded bitumen can be explained by quantitative variations in its group chemical composition and molecular fragments. Group chemical composition has been determined by the method of absorption chromatography, and the fragments of molecules are identified by NMR-spectroscopy.

Disposal of plastic waste in the environment is considered to be a big problem because it is very low in biodegradability and its presence is large. Chocolate,chocolate,chips,handbags,cold drink bottles and other plastic packaging can cause major environmental and economic problems. They consume a lot of energy and other natural resources and exhaust the environment in various ways. In recent years,the use of industrial waste to replace a part of conventional concrete aggregate is being studied. Most of Indian plastic recycling occurred. Up to 60% of industrial and municipal plastic waste is recycled and available from various sources. The Indians release large quantities of plastic waste with enormous economic value. Therefore,the recycling of plastic waste plays an important role in job creation. The "Maale" village located in the Pune district proposes a 2.8 kilometer road suggestion to use the asphalt blend. Building asphalt mixed plastic roads in the village can reduce the plastic waste generated i n the village. The adhesion properties of bitumen can be changed by mixing with plastic waste. It can be used for building purposes. In this paper,we propose construction of asphalt mixed plastic roads addressing the problem of non - biodegradable waste in Pune's "MAALE" village https://www.ijiert.org/paper-details?paper_id=141120

Organo-modified nanoclay has got considerable attention in recent years to improve the performance of asphalt binders. However, various aspects such as rutting performance using Multiple Stress Creep Recovery (MSCR) test, fatigue performance using Linear Amplitude Sweep (LAS) test and ageing resistivity potential using advanced rheological parameter are still unexplored for better rheological characterisation. The present study deals with rutting, ageing resistivity potential and fatigue performance of asphalt binder (AC-10) modified with organo-modified nanoclay (CL-30B). Different percentages (0, 2, 4 and 6% by weight of binder) of CL-30B were mixed with AC-10 using a high-shear mixer. Different rheological studies, such as Brookfield viscosity, Superpave performance grading, time-temperature sweep, MSCR and LAS tests, were conducted on CL-30B-modified asphalt binders. Effects of CL-30B on performance were observed to be predominant in intermediate to high-temperature range as obtained from the master curve. The ageing resistivity of asphalt binder increased with the addition of CL-30B. The Superpave rutting parameter (G*/Sin delta) increased and non-recoverable creep compliance (J(nr)) estimated from MSCR decreased with inclusion of CL-30B, indicating a better rutting performance of asphalt binders. The number of cycles to fatigue estimated from the LAS test showed improvement in fatigue performance of asphalt binder with addition of CL-30B. The high-temperature performance grade of CL-30B-modified binder was found to be higher compared to virgin binder. The relationship between J(nr) and G*/Sin delta, and recovery (R) and storage modulus (G') parameters are presented in this paper. In addition, ranking of asphalt binder based on various parameters (i.e. G*/Sin delta, AI, J(nr), R, N-f) is discussed in this paper.

In this paper, an attempt was made (through theoretical analysis) to solve the problem of fatigue life and strength of an asphalt material modified with crumb rubber. The authors used the developed earlier idea of the possibility of micro-cracks propagation retardation and their arrest in heterogeneous systems (Kaplan and Chekunaev (2010)). In this paper, the authors calculated size of crumb rubber particles significantly slowing down rate of microcracks conversion into macrocracks. It was shown that the most optimal size of bitumen modifier particles (crumb rubber) is ultra-small (200 - 600 nm).

The use of steel slag, as an alternative to natural aggregate, contributes to sustainable development. Potential dimensional instability of the slag aggregate is a concern for use in construction, especially in hot climates. This paper investigates the potential use of steel slag aggregate to replace imported aggregate in hot mix asphalt in Qatar. Laboratory expansion tests and a weathering trial were conducted to assess the long-term expansion properties of the slag. Asphalt mixtures were developed in the laboratory with steel slag aggregate of different sizes and content, and selected mixtures were trialled in a full-scale road section. Field performance was evaluated immediately after construction and after three years in service. Whilst the slag mineralogy indicated the presence of unhydrated lime, the laboratory test and weathering trial confirmed low susceptibility to expansive reactions. Increasing the slag content resulted in higher optimum bitumen content. Coarse slag aggregate was more effective than fine slag aggregate in achieving the Marshall Mix design requirements. The field performance showed improved resistance of the slag asphalt to deformation, with no adverse effect on moisture susceptibility or bitumen ageing compared to the control mix.

This paper focuses on the examination of interdependence of thickness of bitumen sheets and strength characteristics of their mechanically fastened joints. Bitumen sheets with two different thicknesses, which are to be used as single-layer mechanically fastened waterproofing membranes, were chosen as samples for experimental measurements. The aforementioned dependence has still not been explicitly documented. The aim of this paper is to confirm or refute the hypothesis that a relationship exists between different thicknesses of bitumen sheets and strength of their joints. The formulation of the results was based on statistical evaluation of laboratory measurement data. Použití jednovrstvého mechanicky kotveného systému spočívá především v dodržení základních požadavků a dále technologických předpisů stanovených výrobcem. Pro jednovrstvé systémy z asfaltových pásů se používají vysoce kvalitní asfaltové pásy s celkovou tloušťkou min. 5,0 mm. Vyjímečně se lze setkat s asfaltovými pásy určenými pro jednovrstvé systémy, které mají tloušťku pouze 4,0 mm. Z hlediska zajištění dlouhodobé trvanlivosti a hydroizolační bezpečnosti je však jejich aplikace diskutabilní. Asfaltová krycí hmota musí být dostatečně kvalitní, aby zajistila dobrou svařitelnost a dlouhodobou flexibilitu. Pásy jsou nejčastěji vyztuženy spřaženou nosnou vložkou z PES rouna vyztuženého skleněnými vlákny. Kritickým místem spojů je přítomnost kotevního prvku jako místa, kde jsou zachyceny silové účinky vyvolané sáním větru. Plnoplošné natavení dostatečné šířky spoje je základní požadavek pro zajištění hydroizolační schopnost systému a přenesení silových účinků vyvolané sáním větru.

The paper presents the proposition of special assessment of low temperature requirements for bitumens in the region of Central and Eastern Europe where there is a moderate transitional area from sea to the continental type of climate. The results of the research program conducted on the road neat bitumens, Styrene-Butadiene-Styrene polymer and polymer-rubber modified bitumen, and multigrade bitumen types were presented and discussed. Based on the Superior Performing Asphalt Pavements Performance Grade procedure for low temperatures, climatic zones in Poland were developed and compared to analogous zones for other countries from the Central and Eastern Europe region as Estonia and Belarus. The results of functional Performance Grade tests and European standard test of bituminous binders were analysed. It was concluded that some of the bitumens were not meet the performance requirements in the range of low temperatures by Superior Performing Asphalt Pavements Superpave specification and the low-temperature properties of those bitumens should be improved.

The quantification of moisture susceptibility has been a major concern for researchers as it adversely affects the performance of asphalt pavements. Several methods have been developed to assess bond strength using asphalt mixtures in loose and compacted state. These tests lack in their ability to study fundamental properties that affect the bond between bitumen and aggregate. In this context, more fundamental techniques have been developed such as pull-off stub tests and direct tension tests. The first group only measures the maximum pull-off strength and second group has problems related to use of consistent binder film thickness and operational difficulties in test itself. This paper presents a new test to evaluate bond strength, in an attempt, to solve problems associated with traditional direct tension tests. The aim is achieved through a review of existing techniques, development of a gap assembly, fabrication of direct tension test moulds, development of Compression Pull-Off Test (CPOT) and evaluation of its results. The key parameters for bitumen and mastics were evaluated. The CPOT shows promising results for use of this technique to study cohesive as well as adhesive bond strength of binder.

Bitumen is one of the basic building materials that is mainly used in road construction. Nowadays, we can observe increased requirements for the quality of bituminous binders, which are due to increased traffic loads, changing climate conditions, and decreasing crude oil stocks. Besides “traditional” (empirical) tests (softening point, penetration), new types of tests have been developed that can better describe the quality and behavior of bitumen binders. Their composition can also be a significant part of the properties themselves. Therefore, the elemental and group composition of bitumen must also be observed. The use of the viscosity temperature susceptibility (VTS) test appears to be well suited to evaluate the properties of bitumen binders. The VTS parameter is directly dependent on the viscosity of bitumen, but it is necessary to say that VTS can be significantly affected by the composition of the bitumen. The paper is focused on determining the dependencies between the VTS and the bitumen’s composition, respectively, to find out how the composition influences the VTS.

Measurements of total organic content and extractable bitumen for a number of different grade oil sands were used to obtain the extraction efficiency of several common bench-scale bitumen recovery techniques. The hot-water process was inefficient for feeds of moderate to high fines content. Soxhlet extraction and spherical agglomeration were found to be of similar efficiency for most grades of feed. For these two processes the efficiency is limited by the mineral fines content, probably because of surface absorption of bitumen components.

El objetivo de este artículo es estudiar la influencia del polvo de neumático en la mejora de la cohesión proporcionada por la adición del polvo de neumático al betún mediante el método UCL. El método UCL es un procedimiento desarrollado para caracterizar ligantes bituminosos, basado en la evaluación de la cohesión dada por una cantidad determinada de un betún o un mástico bituminoso a unos áridos de granulometría establecida (mezcla patrón). Se ha empleado este método porque permite valorar al mismo tiempo los dos procedimientos de incorporación del polvo de neumático al betún: vía seca y vía húmeda. El procedimiento seco se lleva a cabo añadiendo el polvo de neumático a la mezcla como si fuera un filler, de modo que el polvo de neumático y el ligante se mezclan durante la fabricación, extendido y compactación de la mezcla. En el procedimiento húmedo, hay una mezcla previa del ligante con el polvo de neumático, por lo que aquél seaña de a la mezcla cuando ya ha sido modificado. También se ha estudiado la influencia de los tiempos de digestión. Se comparan los dos procedimientos, seco con y sin digestión, y húmedo. El segundo presenta una clara ventaja,especialmente cuando los ligantes son fabricados con dispersión microscópica.