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Wyniki wyszukiwania dla: RHEOLOGICAL PROPERTIES OF ASPHALT
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Laboratory Determination of Burger's Model Parameters for Visco-elastic Analysis of Road Pavement Materials
PublikacjaBurger's Model is one of those models that describes performance of asphalt mixtures. Its parameters can be used in road construction analysis based on visco-elastic properties in wide variety of temperatures using dedicated programs (e.g. Veroad) or in Finite Element Method (FEM). Parameters of Burger's Model can be used for example in prediction of low temperature cracking in low winter temperatures or permanent deformation...
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Verification of the new viscoelastic method of thermal stress calculation in asphalt layers of pavements
PublikacjaThe new viscoelastic method of thermal stress calculations in asphalt layers has been developed and published recently by the author. This paper presents verification of this method. The verification is based on the comparison of the results of calculations with results of testing of thermal stresses in Thermal Stress Restrained Specimen Test. The calculations of thermal stresses according to the new method were based on rheological...
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Comparison of elastic and viscoelastic analysis of asphalt pavement at high temperature
PublikacjaThere are many various rheological models which are used for modeling of asphalt layers in flexible pavement structures. It can be expected that the use of various models may affect different results of mechanical pavement calculations and analysis. The paper presents comparison of the use of Burgers’ and Huet-Sayegh’s viscoelastic models and Hooke’s elastic model to calculate pavement deflections and strains at the bottom of asphalt...
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Modelling of Asphalt Mixes under Long Time Creep at Low Temperatures
PublikacjaProper description of asphalt mixtures behavior under long time load is one of the most important factors in analyses of strain and stress relations at low temperatures both from traffic and environmental loads. For example different models of thermal stress accumulation require different approaches of description of asphalt concrete. But in all cases it is required to describe its behavior under long time loading, which in some...
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Testing of low temperature behaviour of asphalt mixtures in bending creep test
PublikacjaThe paper presents a method of bending beam test and its importance for evaluation of asphalt mixtures behaviour at low temperatures. Two types of asphalt mixtures: asphalt concrete AC with normal paving grade bitumen and stone mastic asphalt SMA with SBS-modified bitumen were tested. Long-term oven ageing (LTOA) test was also used in the laboratory according to SHRP procedure. The Burgers model was applied and rheological parameters...
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Stiffness of cold-recycled mixtures under variable deformation conditions in the IT-CY test
PublikacjaStiffness modulus belongs to the most important properties describing the cold-recycled mixtures (CRM) in terms of their usability in road pavement structures. Previous research proved that this property is strongly dependent on the scheme and conditions of the test (temperature and time of loading) and the time that has passed since the compaction of the specimen or pavement layer. It is a result of the influence of two different...
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Advancing sustainable hybrid bitumen systems: A compatibilization solution by functionalized polyolefins for enhanced crumb rubber content in bitumen
PublikacjaPolymer waste pollution has a profound effect on the environment and, consequently, on the lifestyle of hu- mankind. The massive production and disposal of cross-linked polymers clearly exemplify the challenges of recycling. Increasing efforts are being undertaken to introduce recycled polymers, especially crumb rubber (CR), into asphalt formulations. Due to the rather poor processability and phase separation associated with CR- modified...
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Sestaveni Smerne Krivky Modulu Tuhosti Pro Zkoumani Nizkotrplotnich Vlastnosti (Developing of Stiffness Master Curve for Analysis of Low Temperature Properties)
PublikacjaV prispevku je predstaven novy postup pro sestrojeni smernych tuhostnich krivek. Nizkoteplotni vlastnosti asfaltove smesi byly stanoveny za vyuziti zkousky dotvarovani pri tribodovem ohybu. Motivem tohoto vyzkumu je skutecnost, ze metody hodnoceni nizkoteplotniho chovani asfaltovych smesi, nove zavedenych v Polsku, nejsou dostatecne. V zaveru jsou prezentovany smerne krivky tuhosti beznych asfaltovych smesi vyuzivanych v Polsku.
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Strain-dependent behaviour of cold recycled material mixtures in cyclic compression tests
PublikacjaThe purpose of the study is to evaluate strain-dependent behaviour of Cold Recycled Material (CRM) mixtures using three frameworks typically applied for Hot Mix Asphalt (HMA): linear viscoelastic (LVE) limits; non-linearity directions; changes in rheological model parameters. To this aim, the complex modulus of three CRM mixtures with different bitumen-to-cement ratio (0.2, 0.6 and 1.8) was measured in cyclic compression mode,...
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Przegląd nanododatków stosowanych w warstwach asfaltowych nawierzchni drogowych
PublikacjaJednym z kierunków rozwoju technologii materiałowych jest nanotechnologia rozumiana jako dziedzina zajmująca się zastosowaniem nanododatków do wytwarzania nowych materiałów oraz ich wpływem na parametry modyfikowanych materiałów. W ostatnich latach nanotechnologia wkracza do technologii modyfikacji asfaltów stosowanych w nawierzchniach drogowych. W artykule przedstawiono stosowane obecnie w budownictwie drogowym nanododatki oraz...
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Sczepność międzywarstwowa w nowobudowanych nawierzchniach w Polsce
PublikacjaW artykule przedstawiono analizę wyników badań sczepności międzywarstwowej warstw asfaltowych przeprowadzonych na podstawie danych z monitoringu właściwości fizyko-mechanicznych warstw asfaltowych z lat 2012-2013. Monitoring prowadziły Laboratoria Drogowe oddziałów GDDKiA w ramach własnych badań kontrolnych podczas realizowanych inwestycji. Analizie poddano 7043 wyników badań sczepności międzywarstwowej badanych próbek, odwierconych...
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Wpływ zbrojenia polimerowymi włóknami rozproszonymi na wybrane właściwości mieszanek mineralno-asfaltowych
PublikacjaW artykule przedstawiono wybrane wyniki badań mieszanek mineralno-asfaltowych zbrojonych polimerowymi włóknami rozproszonymi. Ocenie poddano mieszankę włókien zbrojących aramidowo-poliolifenowych pod kątem wpływu ich zastosowania na właściwości niskotemperaturowe i odporności na deformacje trwałe mieszanek mineralno-asfaltowych. Właściwości niskotemperaturowe oceniano na podstawie testu zginania próbek belkowych oraz na podstawie...
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Influence of Asphalt Binder on the Compactability of Asphalt Mixtures Using Locking Point
PublikacjaCompaction is an important process for the asphalt mixture service life. A properly compacted mixture is crucial for long-lasting pavement. The objective of this study was to evaluate the influence of asphalt binders on the compactability of the asphalt mixtures by utilizing the concept of the locking point. To achieve this objective, two compaction methods (impact and gyration), different temperatures and asphalt content, and...
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Influence of Selected Warm Mix Asphalt Additives on Cracking Susceptibility of Asphalt Mixtures
PublikacjaWarm mix asphalt (WMA) has been widely accepted as a future asphalt paving technology. Besides clear advantages, there are still some concerns regarding durability and long-term performance of pavements made with this type of asphalt mixtures. One of the most important issues is low temperature behaviour of WMA because certain additives used for temperature reduction can aect bitumen properties. This paper presents the evaluation...
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Modification of thermal and rheological characteristics of bitumen by waste PET/GTR blends
PublikacjaWaste poly(ethylene terephthalate) (wPET)/ground tire rubber (GTR) blends with variable compositions were applied as low-cost modifiers into bitumen and their performance has been evaluated via morphological, thermal and rheological analyses. Depending on the weight ratio of wPET/GTR, dispersion of single/composite domains of waste polymers in the bitumen has promoted the interaction between bitumen and blend components. Fourier...
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Influence of low-temperature physical hardening on stiffness and tensile strength of asphalt concrete and stone mastic asphalt
PublikacjaThis paper presents laboratory testing of stiffness modulus and indirect tensile strength of three asphalt concrete (AC) and three stone mastic asphalt (SMA) mixes after isothermal storage at temperature of -20oC, at different time intervals up to 16 days. The tests under repeated dynamic loading showed physical hardening of all tested mixes which was manifested by an evident increase of their stiffness moduli after isothermal...
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Assessment of Tensile Strength Reserve of Asphalt Mixtures at Low Temperatures
PublikacjaDuring winter conditions, low-temperature cracks develop at the surface of the asphalt pavement when tensile thermal stress induced in the asphalt layer during cooling equals and exceeds the tensile strength of the material. The paper presents the results of tensile strength reserve assessment of asphalt mixtures with neat and SBS-polymer modified bitumen application. The tensile strength reservewas calculated as difference between...
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Comparison of low-temperature cracks intensity on pavements with high modulus asphalt concrete and conventional asphalt concrete bases
PublikacjaHigh modulus asphalt concrete (HMAC) base courses provide very good resistance to rutting and fatigue but they can increase the risk of low-temperature cracking as compared with conventional asphalt concrete (AC). The article presents the comparison of these two road materials in terms of low-temperature cracking. The statistical method based on the ordered logistic regression model was used. The analysis was based on results of...
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Influence of selected WMA additives on viscoelastic behaviour of asphalt mixes and pavements
PublikacjaWarm mix asphalt additives are effective in decreasing production, laying and compaction temperatures of asphalt mixes. However, there are still questions concerning influence of warm mix additives on properties of asphalt mixes and pavement performance. This paper presents results of the comprehensive research of viscoelastic behaviour of asphalt mixes and pavement structures with layers made with warm mix asphalt additives at...
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Equivalent temperature for design of asphalt pavements in Poland
PublikacjaThe paper presents application of equivalent temperature for design of asphalt pavements. The calculation methods of equivalent temperature: the Shell method, the French method, the methods that use the AASHTO and the Asphalt Institute fatigue criteria were presented. The results of calculations of equivalent temperature for Polish climatic conditions were presented and discussed. It was shown that different asphalt pavement design...
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Evaluation of thermal cracking probability for asphalt concretes with high percentage of RAP
PublikacjaThe paper presents determination of the probability of thermal cracking of asphalt mixtures with different reclaimed asphalt pavement (RAP) content on the basis of laboratory tests and analytical evaluation using thermal stress development method. Probability was evaluated taking into consideration: the type and gradation of the mixture and the quality and content of RAP. Thermal stresses were determined using two models: elastic and...
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Effect of modified soybeen oil amount on rheological characteriza-tion of polyurethane pre-polymers
PublikacjaPolyurethanes (Pu’s) are the polymeric materials which have got urethane groups in the structure. The properties of Pu’s depend both on the method of preparation and monomers used. Polyurethanes are produced by two methods known as one step or two step method called as “pre-polymers method”, especially for the case of segmented polyurethanes (SPU’s). These materials are thermoplastic block copolymers of the (AB)n type consisting...
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The Impact of Homogeneity of High Modulus Asphalt Concrete Layer on Low-Temperature Cracking
PublikacjaDuring winter season of 2012 numerous transverse cracks developed in high-modulus asphalt concrete (HMAC) base of newly constructed motorway. Pavement cracked both in transverse joint locations and in the area between them. Research which was conducted during investigation of the causes and mechanisms of cracking consisted of: field examination, laboratory testing of specimens cored out of the existing pavement, computational analyses...
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Development and application of asphalt binder relaxation test in different dynamic shear rheometers
PublikacjaIn this study, a novel relaxation test is proposed to evaluate asphalt binder low temperature properties using a Dynamic Shear Rheometer (DSR) with parallel plates of 4 mm in diameter. Three rheometers from three different manufacturers are used to analyze seven asphalt binders. Different material parameters are derived which are useful to evaluate and discriminate different asphalt binders. Test results of all three instruments...
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Crack Resistance of Asphalt Concrete Subjected to Environmental Factors
PublikacjaThe paper presents an analysis of the influence of environmental factors on the cracking susceptibility of asphalt concrete resulting in a change in the durability of asphalt pavement. In order to assess the phenomenon, laboratory tests were carried out taking into account the destructive effects of moisture, freeze-thaw cycle and long-term ageing. The influence of both factors occurring simultaneously was also verified. Due to...
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Asphalt Overlay Enhancement with Fatigue High-Performing Multiaxial Geocomposite
PublikacjaThe use of gecomposite incorporating multiaxial geogrid and non-woven fabric of high bitumen retention in asphalt overlays results in the increase of life of the designed pavement structure. Such an approach can offer an opportunity to increase the fatigue life (higher traffic capacity) without the need to increase asphalt overlay thickness or to reduce the thickness of asphalt overlay without reduction of pavement life eventually....
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A mathematical model of rheological behavior of novel bio-based isocyanate-terminated polyurethane prepolymers
PublikacjaIn this paper, the results of rheological study on isocyanate-terminated polyurethane prepolymers, containing modified soybean oil residues incorporated into the chemical structure are described. Isocyanate-terminated prepolymers were synthesized from 4,4′-diphenylmethane diisocyanate and the mixture of hydroxylated soybean oil and commercial polyether. The measurements were performed by using rotary rheometer R/S-CPS+ (Brookfield,...
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The Effect of Water and Frost on Fatigue Life of Asphalt Concrete
PublikacjaThis paper presents testing of fatigue life of asphalt concrete that has been subjected to action of water and frost. Simulation of water and frost action was based on the original AASHTO T283 method and its modification. The original method was modified in such a way that instead of a single freeze-thaw cycle, 50 and 150 cycles were applied. Fatigue life was measured in the indirect tensile fatigue test in the Nottingham asphalt...
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Comparison of calculated and measured thermal stresses in asphalt concrete
PublikacjaThe paper presents the comparison of calculated and measured thermal stresses induced in restrained asphalt concrete specimens by cooling. Thermal stresses were measured in the Thermal Stress Restrained Specimen Test. The calculations of thermal stresses were performed with the use of a theoretical formula based on the temperature dependent stiffness modulus. The novel approach applied in this paper was that the stiffness modulus...
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Influence of bitumen type on cracking resistance of asphalt mixtures used in pavement overlays
PublikacjaCracking is one of the predominant distresses occurring in flexible pavements, especially in old pavements that were rehabilitated with an asphalt overlay. In such cases asphalt mixtures should be designed to ensure high resistance to reflective cracking because new asphalt layers are exposed to existing cracks of the old pavement. The nature of these cracks can be various (transverse, longitudinal as well as crazy cracking). One...
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Numerical simulation of asphalt mixtures fracture using continuum models
PublikacjaThe paper considers numerical models of fracture processes of semi-circular asphalt mixture specimens subjected to three-point bending. Parameter calibration of the asphalt mixture constitutive models requires advanced, complex experimental test procedures. The highly non-homogeneous material is numerically modelled by a quasicontinuum model. The computational parameters are averaged data of the components, i.e. asphalt, aggregate...
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Durability of Asphalt Concrete Subjected to Deteriorating Effects of Water and Frost
PublikacjaThe paper presents testing of the detrimental effects of water and frost on asphalt pavements. It included laboratory testing of 5 fatigue life of asphalt concrete that was subjected to action of water and frost and field testing of damages caused by water and frost on 6 existing asphalt pavements, such as stripping, raveling, and potholes. Laboratory simulation of water and frost action was based on the 7 original AASHTO T283...
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Enhancing rheological muscle models with stochastic processes
PublikacjaPurpose: Biological musculoskeletal systems operate under variable conditions. Muscle stiffness, activation signals, and loads change during each movement. The presence of noise and different harmonic components in force production significantly influences the behaviour of the muscular system. Therefore, it is essential to consider these factors in numerical simulations. Methods: This study aims to develop a rheological mathematical...
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Effect of interlayer bonding quality of asphalt layers on pavement performance
PublikacjaThe quality of interlayer bonding at the interfaces between the asphalt layers in flexible pavements affects the overall pavement performance. Lack or partial lack of interlayer bonding between asphalt layers can cause pavement's premature failures such as rutting, slippage of the wearing course, cracking or simply a reduction in the calculated fatigue life of the pavement structure. This paper shows the case studies of investigation...
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Fracture susceptibility of high RAP content asphalt concrete in terms of aging
PublikacjaDue to the reduction of CO2 emissions during the production of asphalt mixtures and the decrease in the demand for mineral resources, the addition of reclaimed asphalt pavement (RAP) is becoming indispensable. The durability of asphalt pavements containing a high RAP content may be reduced due to a decrease in the cracking resistance of the material, especially under the influence of operational aging. The article presents the...
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Influence of compaction effectiveness on interlayer bonding of asphalt layers
PublikacjaThe paper presents the results of research on the interlayer bonding of asphalt layers compacted in the laboratory and in the field. To measure the interlayer bonding at a temperature of 20°C the Leutner test apparatus was used and load was applied at a rate of 50 mm/minute. Three types of interlayer interfaces were tested: no tack coat and tack coats made of two types of the pure bitumen emulsions. Four compaction techniques were...
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Field Evaluation of High Modulus Asphalt Concrete Resistance to Low-Temperature Cracking
PublikacjaHigh-modulus asphalt concrete has numerous advantages in comparison to conventional asphalt concrete, including increased resistance to permanent deformations and increased pavement fatigue life. However, previous studies have shown that the construction of road pavements with High Modulus Asphalt Concrete (HMAC) may significantly increase the risk of low-temperature cracking. Those observations were the motivation for the research...
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Evaluation of Thermal Stresses in Asphalt Layers in Comparison with TSRST Test Results
PublikacjaThe paper presents the results of calculations and laboratory determination of thermal stresses at low temperatures. The modified Hills and Brien's method was used to calculate the thermal stresses in asphalt layers of pavements and the results were compared against the values obtained at a laboratory with the Thermal Stress Restrained Specimen Test (TSRST) method. The laboratory investigations were conducted using plain grade...
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Reduction of noise and rolling resistance by horizontal grinding of asphalt pavements
PublikacjaGrinding of cement concrete pavements to reduce unevenness and noise is common since a long time. Grinding is then made with wheels equipped with diamond blades rotating in the vertical plane. This creates narrow vertical/longitudinal grooves in the pavement. It is not applied to asphalt pavements. In this paper an alternative type of grinding is studied. In this case plates with diamond heads rotate in the same plane as the pavement,...
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Rolling Resistance And Tire/Road Noise on Rubberized Asphalt Pavement In Poland
PublikacjaThe paper presents results of tire/road noise and rolling resistance measurements performed on stone-matrix asphalt (SMA) that contains rubberized asphalt developed and produced by the company in Poland. Bituminous binder was modified with polymer and additive of crumb rubber. First observations of asphalt mixture with the new kind of modified bitumen used on the field section are presented. Rolling resistance of passenger car...
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Rolling resistance and tyre/road noise on rubberised asphalt pavement in Poland
PublikacjaThe paper presents results of tyre/road noise and rolling resistance measurements performed on stone mastics asphalt (SMA) that contains rubberised asphalt, developed and produced by a refinery in Poland. Bituminous binder was modified with polymer and addition of crumb rubber. The first observations of asphalt mixture with the new kind of modified bitumen used on the field section are presented. Rolling resistance of passenger...
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Advanced fatigue and rutting characterisation of Polish asphalt mixtures based on the VECD model and viscoplastic shift model
PublikacjaThe advanced asphalt mixture performance-related specifications (AM-PRS) recently developed in USA can allow an optimisation of the design process of asphalt pavements thanks to the possibility to fully take into account the intrinsic material properties. In this study, four typical Polish mixtures, i.e. a Stone Mastic Asphalt (SMA) for wearing course, two mixtures for binder course with neat bitumen or Polymer modified Bitumen...
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Rheological Problems of Technical Fabirc
PublikacjaW pracy przedstawiono wyniki identyfikacji modeli Chaboche'a i Schapery dla tkaniny technicznej Panama.
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Evaluation of Asphalt Mixture Low-Temperature Performance in Bending Beam Creep Test
PublikacjaLow-temperature cracking is one of the most common road pavement distress types in Poland. While bitumen performance can be evaluated in detail using bending beam rheometer (BBR) or dynamic shear rheometer (DSR) tests, none of the normalized test methods gives a comprehensive representation of low-temperature performance of the asphalt mixtures. This article presents the Bending Beam Creep test performed at temperatures from −20...
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The best porous asphalt pavement in Sweden so far
PublikacjaIn 2010 a double-layer porous asphalt concrete (DPAC) pavement was constructed in various versions on the E4 motorway through the Swedish city Huskvarna. As a result of a court decision the Swedish Transport Administration had to reduce noise emission by applying a low noise road surface that would reduce A-weighted noise levels by 5 dB, as an average. Earlier experience in Sweden indicated that it was possible to obtain a high...
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Thermal stabilization and permanent deformation resistance of LWA/PCM-modified asphalt road surfaces
PublikacjaThis paper presents the results of attempts at reducing the problem of solar overheating of asphalt road pavement surfaces, resulting in weakening and accelerated destruction of the aforementioned structures. To protect pavement surfaces against periodic overheating, standard asphalt mixture AC 16 W 35/50, used for binder course, has been modified by replacing one of the aggregate fractions from the mineral mixture with lightweight...
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Rheological characteristics of oligomeric semiproducts gained via chemical degradation of polyurethane foam using crude glycerin in the presence of different catalysts
PublikacjaPolyurethane (PU) recycling is a topic of growing interest due to the increasing amount of polyurethane waste. The main purpose of polyurethane chemical recycling is to recover the starting polyol. In this study, a method of polyurethane thermochemical recycling, glycerolysis by means of crude glycerin, is proposed. This work presents a comparative study of commercial catalysts used in order to accelerate the decomposition process,...
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The statistical impact of experimental result scatter of asphalt mixtures on their numerical modelling
PublikacjaThe paper presents selected test results of asphalt mixture conducted in low temperatures. The obtained parameters are highly diverse. It concerns ultimate breaking loads, stiffness parameters related to Young's modulus but also the fracture course. Statistical analysis upon the results makes it possible to relevantly estimate the material-defining parameter values. Such a random approach leads to the mean values of breaking and...
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Verification of the criteria for evaluation of water and frost resistance of asphalt concrete
PublikacjaThe paper presents the results of field investigation - condition survey of existing pavements and the results of laboratory tests on water and frost resistance of samples cored from the these pavements. The purpose of testing was to verify the criteria for evaluation of the resistance of asphalt concrete to the action of water and frost by way of comparing the results of field and laboratory tests, followed by evaluation of their...
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Consideration of Pseudo Strain Energy in Determination of Fatigue Life and Microdamage Healing of Asphalt Mastics
PublikacjaRest periods between cyclic loads can lead to recovery of damage and extension of fatigue life. This phenomenon is referred to as healing. Healing is clearly observed in bituminous materials, such as asphalt mastics, which belong to the components of asphalt mixtures. Due to the nature of road pavement traffic loading, which is characterized by series of intermittent pulses with rest periods, consideration of healing is necessary...