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Heavy traffic reduces the strength characteristics of asphalt concrete, causes peeling on the pavement. Crushed stone-mastic asphalt concrete is designed for the device of the upper layers of the coating on roads with high traffic intensity. The use of polymerasfalt concrete on a modified binder can lead to an improvement in the physical and mechanical characteristics of asphalt concrete and increase its re-sistance to climatic influences. The main aspects of improving the quality of crushed stone-mastic as-phalt concrete (SMA) due to the use of a binder modified with sevilen (SEVA) are discussed. The effect of bitumen containing sevilen with 22 and 29 % vinyl acetate groups on the properties of crushed stone-mastic asphalt concrete has been investigated. Analysis of the results showes that the use of modified binders has a positive effect on the entire complex of physical and mechanical parameters of polymer asphalt concrete. An increase in the strength of the samples at 20 and 50 °C, a decrease in this indicator at 0 °C is established. The indicators of water and heat resistance, shear resistance and crack resistance are also improved, which should have a positive effect on the durability of the road surface. Rational concentrations of polymer additives and the amount of vinyl acetate groups in its composition have been established. The adhesion of the binder to the mineral part of the asphalt con-crete mixture is estimated. The index of sensitivity to temperature differences of asphalt concrete sam-ples is considered due to the fact that asphalt concrete is a material that reacts to temperature fluctua-tions in the external environment. The analysis of the results of the tests carried out demonstrates that the use of modified binders has a positive effect on the entire complex of physical and mechanical pa-rameters of polymer asphalt concrete.

Introduction. Transport times of hot asphalt from its production facility to the road section of laying depends of the distance of the asphalt mixing plants location, also in urban conditions it depends from the intensity of traffic flows, the number of traffic jams on the way of the dump truck.Problems. At the present stage, a sharp decrease of road pavement quality and durability occurs due to an increase of the number of heavy vehicles, an increase of axle loads on the pavement and an increase in the speed limit, due to use of outdated technologies that not correspond to the existing loads by their technical characteristics.Purpose. To analyze the modern technology of crushed stone — mastic asphalt transportation in order to determine the shortcomings in its application.Materials and methods. Analysis of information sources, including foreign sources regarding transportation technologiesResults.Possible consequences of non-observance of the correct transportation technology and their elimination have been determined.Conclusions. During the transportation of crushed stone — mastic asphalt mixture, the temperature and fractional segregation (dissection) of the hot mixture occurs. The main factors that cause it are following: ambient temperature, air humidity, wind speed, bulk filling, transport times, pavement flatness during transportation. To prevent the segregation appearance, it is need to increase the loading rate of the dump truck bulk, using heat-insulating elements during transportation (awnings, metal covers, etc.), also as thorough cleaning of the dump truck bulk surface from any residuals of bituminous and other materials before each loading of crushed stone-mastic asphalt.Keywords: crushed stone-mastic asphalt, temperature segregation, transportation technology.

Rutting is an important problem in Russia today. One of the ways to improve the properties of asphalt concrete mixtures and reduce wear on road surfaces is to modify the binder with polymer additives. The aim of the work was to test the selected compositions of MMAC mixtures containing bitumen modified with the addition of sevilene and rubber for rutting resistance, which make it possible to predict the formation of plastic rut. It was revealed that when using sevilen in its composition, with an increase in the concentration of vinyl acetate, the depth of the track increases in comparison with the industrial polymer-bitumen binder. It is shown that with the introduction of a complex additive based on sevilen and rubber into the binder composition, its rutting decreases and the service life of the road surface increases, which indicates a high elasticity of the complex-modified binder. In this work, the calculation of the service life of the coating before the formation of a critical rut requiring repair of the coating is carried out. It was found that in terms of the slope of the rutting curve and the proportional depth of the rut, the compositions with sevilene and rubber are not inferior to traditional industrial PBB.

One of the main reasons for reducing the service life of road asphalt pavements (the appearance and development of damage in the form of ruts, various kinds of plastic deformations, potholes, cracks, etc.) is the low quality of the used oil bitumen. The physicomechanical properties of road bitumen are subject to stricter requirements, especially for organic binders used for the production of crushed stone mastic asphalt (SMA), therefore, in authors’ view, the development of bitumen binders with enhanced physicomechanical properties is one of the key and most urgent tasks in road construction. This problem is solved by introducing various modifiers into the binder. This article presents the results of a study of bitumen modified by introducing technical sulfur into the composition. The effect of binder modification on the physicomechanical properties of road asphalt concrete is shown on the example of crushed stone mastic asphalt (SMA-20) relative to base samples made to control the dynamics of changes in the properties of composites made using sulfur-raising technologies. For a comprehensive assessment of the effectiveness of modifying crushed stone mastic asphalt concrete based on various binders, a generalized quality criterion is calculated, taking into account the calculated particular quality criteria and various values of the weight coefficients. The comparison and analysis of the obtained efficiency criteria is made.

Mastic asphalt is a type of pavement material that has good fluidity and is self-levelling at construction temperature for the bridge deck. There are highly accurate methods and indexes for evaluating fluidity and high-temperature deformation resistance for mastic asphalt-design and construction-control systems. The fatigue cracking is one of the main failure forms of bridge deck pavement. Therefore, the method used to evaluate the fatigue properties of pavement materials is also essential. The anti-deformation capability of the mastic asphalt must be increased, that results in poor fatigue performance and consequent failure of the bridge deck pavement to avoid the rutting of bridge deck pavement. In this study, a simple method is put forward for evaluating mastic asphalt fatigue performance. Impact toughness is defined as the area under the load-displacement curve of a three-point bending beam specimen under impact load to evaluate the fatigue performance of mastic asphalt. The four-point bending beam fatigue test is used to verify the rationality of the impact toughness test method. The results showed that there is a good correlation between the impacts toughness index of mastic asphalt produced under different mixing conditions and the accumulative dissipative energy and fatigue life demonstrated by the four-point bending beam test. Therefore, to evaluate the fatigue performance of mastic asphalt by impact toughness test. Fatigue performance and rut resistance are two ways to evaluate road performance of asphalt mixtures, but they are mutually restrictive. The results show that impact toughness and dynamic stability are inversely correlated. As the impact toughness increases, dynamic stability decreases. Therefore, balancing the fatigue performance and high-temperature rutting resistance of mastic asphalt in the design and quality control is very important.

High-quality and durable asphalt pavement ensures safe and comfortable traffic, optimal logistics costs, territory attractiveness to construction investments, and industrial development. With constantly increasing loads on road pavements, it is necessary to improve the asphalt quality by introducing additives into the mixture, design methodology, scientific justification for the selection and preparation of raw materials. The paper proposes the development algorithm of crushed-stone and mastic asphalt modified by the new stabilizing additive, which consists of 90 % of cellulose fiber from waste paper, 5 % rubber powder, and 5 % bitumen. The optimal particle size distribution of the mineral component in the crushed-stone and mastic asphalt is considered to be 73% of crushed stone with fractions of 15–20, 10–15 and 5–10 mm, 16 % of dolomite sand from crushing screenings, 11 % of mineral powder, 0.4 % of stabilizing additive and 5.5 % of bitumen. The compressive strength of the developed composition is 2.3 times higher than that meeting the requirements of GOST 31015–2002 for the climatic zone II. The research results are confirmed by pilot-industrial tests in constructing the road pavement in Tyumen.

Reclaimed asphalt pavement (RAP) arises from the demolition of asphalt road layers. The Optimal Recycling of Reclaimed Asphalt Pavements Project concerns the cold recycling of 100 % RAP without binder addition in base and subbase layers of low-traffic roads. In this context, a test program was performed with Rhine region materials to evaluate the impact of the mastic coating of untreated RAP. A source of reclaimed asphalts with 4.4 % of bitumen is tested before (RAP) and after binder extraction (RAP-BE) and then is compared to an unbound granular material (UGM) with a similar particle-size distribution. Repeated load triaxial tests were conducted at several frequencies to study the permanent and resilient behaviors. The results show that the RAP before binder extraction and the UGM present similar permanent behaviors, while the aggregates without binder reveal low strains. Concerning the resilient phase, the RAP and the RAP-BE show similar levels of strains, but the resilient moduli of the UGM are significantly lower than those of the RAP. From the experimental results, the nonlinear elastic Boyce model was fitted and brings out a highly anisotropic mechanical behavior of the RAP. Finally, the RAP shows a frequency-sensitive viscous behavior because of the bitumen in the mastic, while the effect of the frequency is negligible for the RAP-BE.

Viscoelastic characterisation of asphalt mixtures is an important component for modelling and performance prediction of flexible pavements. In this study, using spherical indentation testing for measuring the viscoelastic properties of asphalt is explored. Indentation testing may provide an interesting alternative to existing experimental techniques, as it is capable of characterising small material volumes. Thus, it may become a useful tool for the characterisation of thin asphalt layers and for the measurement of binder phase properties in-situ in asphalt mixtures. Spherical indentation tests are performed on two mastic asphalt (MA) mixtures, prepared with different mastic types. The shear relaxation moduli obtained from the indentation tests are compared with the ones measured with seismic and SuperPave Indirect Tensile (IDT) tests. A new statistical analysis methodology is proposed for viscoelastic characterisation of the mastic phase with the indentation tests performed on MA mixtures. The accuracy and sensitivity of the developed method are examined. QC 20211110

Mastic asphalt is a material which in Sweden mainly is used as coating for bridges, parking decks, courtyards and terraces. Mastic asphalt is a material built-up by a combination of bitumen (a type of binder), well-graded aggregate (consists of both coarse and fine ballast), filler, sand and sometimes also fine graded macadam. Mastic asphalt is described as a material which in Sweden have potential to expand further. At the same time, it is becoming increasingly popular to construct buildings with solid timber frames. In 2019, the Swedish market for forestry and algaculture was analyzed, after which cross-laminated timber proved to be the construction-material that increases most in popularity. In constructions, mastic asphalt and timber may be combined. In Växjö Sweden for example, a parking deck called Limnologen is constructed with both timber frames and mastic asphalt as pavement. Another example were mastic asphalt and timber have been combined is an enormous car park built in Studen, Switzerland, which have 2142 parking lots. The aim of this master thesis was to develop a temperature-dependent thermal conductivity (for mastic asphalt BPGJA-11) which resulted in temperature development curves that correlated well with the results presented in Ellinor Sanned’s bachelor thesis “Insulation of timber with concrete and cast asphalt”. Sanned performed laboratory work were two different samples of mastic asphalt was tested in a cone calorimeter. The cone calorimeter was set to 51 kW/m2 and Sanned measured the temperature development beneath the mastic asphalt. The thermal conductivities for mastic asphalt were, in this master thesis, developed by using inverse calculation in the finite element program TASEF (Temperature Analysis in Structures Exposed to Fire). To form a reliable setup in TASEF, a sensitivity analysis was initially conducted. Information regarding thermal properties of mastic asphalt at elevated temperatures was in general considered challenging to find. Due to this, assumptions of the parameters set in TASEF had to be made. The thermal conductivities were developed at 0 ℃, 300 ℃ and 660 ℃. The results indicates that the thermal conductivity of the mastic asphalt (BPGJA-11) tested by Sanned decreases between 0 ℃ and 300 ℃, and then more or less stabilizes. The presented thermal conductivities should however be used with great caution. The reason for this is due to uncertainties in the experimental cone calorimeter results, uncertainties within the setup in TASEF as well as within the specific method used. In particular the application on materials which both melts and boils (such as mastic asphalt) should be made with great care. To increase the reliability of the results, more research and laboratory work should therefore be performed within the area. The method used within this master thesis (inverse calculation using TASEF) is simple and cost effective when determining the thermal conductivity. Mastic asphalt (som i denna sammanfattning benämns som gjutasfalt) är ett material som i Sverige huvudsakligen används som beläggning för broar, parkeringshus, gårdsplaner och terrasser. Gjutasfalt är ett material som är byggt upp av en kombination av bitumen (en typ av bindemedel), välgraderat stenmaterial (består av både grov och fin ballast), filler, sand och ibland även finmakadam. Gjutasfalt beskrivs som ett material som i Sverige har stor potential att expandera. Samtidigt blir det alltmer populärt att konstruera byggnader med solida träkonstruktioner. År 2019 analyserades den svenska marknaden för skog och lantbruk, varpå kors-laminerat trä visade sig vara det konstruktionsmaterial som ökar mest i popularitet. I konstruktioner kan gjutasfalt och trä kombineras. Parkeringshuset Limnologen i Växjö Sverige är ett exempel på en träkonstruktion som kombinerats med gjutasfalt som beläggning. Ett annat exempel är ett enormt parkeringshus i Studen, Schweiz, som har 2142 parkeringsplatser. Målet med denna masteruppsats var att bestämma den temperaturberoende termiska konduktiviteten (för gjutasfalt BPGJA-11) vilken resulterar i en temperaturutvecklingskurva som korrelerar väl med resultaten presenterade i Ellinor Sanneds examensarbete ”Isolering av trä med betong och gjutasfalt”. Sanned genomförde en laboration där två olika prov av gjutasfalt testades i en konkalorimeter. Konkalorimetern var inställd på 51 kW/m2 och Sanned uppmätte temperaturutvecklingen på undersidan av gjutasfalten. De termiska konduktiviteterna för gjutasfalt i denna masteruppsats arbetades fram genom ”inversberäkning” i det finita elementprogrammet TASEF (Temperature Analysis in Structures Exposed To Fire). För att bilda en tillförlitlig uppsättning i TASEF, genomfördes inledningsvis en känslighetsanalys. Information gällande termiska egenskaper av gjutasfalt vid förhöjda temperaturer var generellt sätt svåra att finna. För parametrarna som användes i TASEF gjordes därför antaganden. De termiska konduktiviteterna arbetades fram vid 0 ℃, 300 ℃ and 660 ℃. Resultaten indikerar att den termiska konduktiviteten för den gjutasfalt (BPGJA-11) som testades av Sanned minskar mellan 0 ℃ och 300 ℃, för att därefter mer eller mindre stabiliseras. De termiska konduktiviteterna som har presenteras bör dock användas med stor försiktighet. Anledningen till detta beror på osäkerhet för de resultat som presenterades av Sanned, osäkerheter för uppsättningen i TASEF samt för den specifika metod som används. Speciellt anbefalles försiktighet med att använda metoden för material som både smälter och kokar (såsom gjutasfalt). För att öka resultatens tillförlitlighet bör därför mer forskning och laboratoriearbete utföras inom området. Metoden som har använts inom denna masteruppsats (inversberäkning med TASEF) är enkel och kostnadseffektiv för att bestämma den termiska konduktiviteten.

Mastic asphalt (MA) has been particularly popular in recent years for bridge pavements due to many advantages such as easy application, good waterproofing properties, and high durability. However, the drawback of mastic asphalt in comparison to other asphalt mixtures is its lower resistance to permanent deformation. Trinidad Lake Asphalt (TLA) is often applied to make mastic asphalt resistant to permanent deformation. Practical experience demonstrates that serious failures may occur if MA pavement design and materials selection is not taken into account sufficiently. Therefore in this study, the influence of two parameters: zero shear viscosity (ZSV) of TLA-modified binder and mastic composition described by the filler–binder ratio, on the permanent deformation resistance of the MA mixture was evaluated. The primary purpose of determining the ZSV of the TLA-modified binders was to evaluate the rutting potential of the binders. The permanent deformation (rutting) resistance of the MA mixtures was evaluated based on static and dynamic indentation tests. The optimum content of TLA in the base bitumen and the optimum filler–binder ratio in the MA mixture were obtained based on multiple performance evaluations for modified binder, mastic and MA mixtures, i.e., 20% and 4.0, respectively.

Subject: a rapid increase in the traffic intensity and freight traffic on motor roads leads to premature destruction of road surfaces. At the same time, the actual service life of asphalt-concrete pavements rarely exceeds 4-5 years and in most cases is only 2-3 years. Most intensively defects and fractures appear on asphalt-concrete pavements in the early spring. Nowadays the overhaul intervals for the road surface coverings are significantly lower than those given by the regulatory requirements. One of the main reasons for this phenomenon is the use of obsolete technologies based on traditional materials whose properties are inadequate to resist stresses and deformations arising in the coating. This is especially evident in the climatic conditions of the south of the European part of Russia, where the upper layers of the roadway experience a much wider range of temperatures. Tighter requirements for the initial road-building materials and timely repair of the coatings allow us to increase the service life of motor roads. Research objectives: the aim of the study is to develop a new type of asphalt-concrete, such as porous-mastic one. Materials and methods: the work was carried out based on observations and published sources, a method of theoretical study and analysis. Results: the domestic and foreign experience of using the given asphalt concrete for the top layer of the coating was considered. The technology of preparation and laying of a porous-mastic asphalt-concrete mixture is presented and its advantages and disadvantages are shown. Conclusions: increasing the longevity of highways is an important and urgent task and it can be solved, in particular, due to the wide use of new technologies and non-traditional building materials that allow us to improve the quality of asphalt-concrete pavement and prolong its overhaul intervals.

Problem. The temperature of mastic as-phalts mixing is significantly higher than the one for hot asphalt mixtures. It is due using of high viscous bitumens as a mixture component and realizing the main advantage of mastic asphalt – its ability to flow and compact with its own weight at high tempera-ture. There is no uniform way to assign the process temperatures for mastic asphalt. Goal. To find the process temperatures for mastic asphalt with bitumen binders differ by viscosity as a researching on tem-perature influence and influence of binder concentra-tion on properties of mastic asphalt is a goal of this research work. Methodology. The mastic asphalt mixtures and asphalt concrete with conventional pavement bitumen 70/100 (penetration is 85 dmm) and high viscous bitumen (penetration is 38 dmm) are chosen for research. The mineral aggregates contain 42 % of crushed granite 5-10 mm, 33 % of granite screening and 33 % of limestone powder. The properties of mastic asphalts are evaluated with EN 12697-20:2003, SOU 42.1-37641918-106:2013 and DSTU EN 13108-6:2018. Results. It was found a significant influence of amount and viscosity of bitu-men and a temperature on workability of mastic as-phalt mixture and on properties of mastic asphalt concrete. Originality. The comparative analysis of workability of mastic asphalt mixture and properties of mastic asphalt concrete with bitumens differ in viscosity is a scientific originality of presented re-search. Practical value. Due to research results it is not reasonable to assign the temperature that sup-plies viscosity of 0.5 Pa•s as a temperature of mixing of mastic asphalt. The temperature conditions of mastic asphalt mixing are much higher (200 – 240 °C). To evaluate workability and find a minimal acceptable temperature of mixture it is possible to use the thickness of the mixture layer after spreading as an indicator. With this the acceptable workability of the mastic asphalt mixture can be characterized by thickness of its layer 30 mm or less after spreading.

This study aims to determine the effect of latex addition to the durability of the Split Mastic Asphalt (SMA) pavement mixture in order to increase its durability when the road is flooded. Durability test conducted where the sample was immersed in water for 0, 24, 48, 72, 96 hours, with latex variations of 1.5%, 2%, 2.5%, 3%, 3.5%. From the results of the study it was found that the durability of asphalt mixture without latex was higher than that of SMA with latex. The durability indexes were 6.740%, 10.648, 11.717, 13.884, 14.766 and 9.991 for 0%, 1.5%, 2%, 2.5%, 3%, 3.5% latex in the mixture respectively. The higher the index the lower the strength. In addition, the longer the soaking time the lower the strength. However, as the latex in the mixture increases, the stability was also increase achieved at 3% latex. The SMA pavement mixture with the addition of latex does not increase its durability but can increase its stability value. So, it is recommended that SMA pavement mixture with latex is only for pavement where the water level is not high.

Mastic asphalt (MA) has been recognized as one of the most deformation-resistant and thus durable materials for bridge pavement. The performance properties of MA are highly dependent on the physical and rheological properties of the binder applied in the MA mixture. To modify the binder properties to obtain the expected performance of the MA mixture, Trinidad Lake Asphalt (TLA) is often applied. In this study, the TLA-modified binders to be used in mastic asphalt bridge pavement systems were evaluated to develop the optimum material combination using conventional and performance-related testing. Physical and rheological tests were carried out on TLA-modified binders with the different modifier content in the range of 10–50% on a weight basis. The tests revealed that the TLA modifier addition to the 35/50 base bitumen should be close to the value of 20%. Higher concentrations of TLA may make the binder very stiff and could induce low-temperature cracks in mastic asphalt.

The article shows the results of fatigue life tests of macadam and mastic asphalt concrete made with use of a bituminous binder of various PG marks. The optimal compositions of the samples of macadam and mastic asphalt concrete characterized by close residual porosity to exclude its effect on the physical and mechanical properties and indicators of fatigue life are selected. A Cooper CRT-SA4PT-BB-16 testing machine was used to evaluate the fatigue life of macadam and mastic asphalt concrete, testing beam specimens for four-point bending. The following test protocol was used in the work: a loading frequency of 10 Hz, a test temperature of + 20 ° C, a decrease in the rigidity of the samples to 50% of the initial value and the number of cycles was recorded. Based on the analysis of the obtained dependences: strength indicators, mixture stiffness and fatigue life, it is shown that there is no linear relationship between the mark of bitumen binder and the fatigue life of a road composite made on its basis, therefore, focus on PG mark of bitumen to design the composites of durable asphalt concrete with predetermined properties is not enough.

Ülkemiz dalgalı ve dağlık topografik bir yapıya sahip olmasından dolayı; vadi kesimlerinde iki yükselti arası ve su geçişlerinde ulaşımın sağlanması için viyadük ve köprüler gibi yapılar önemli role sahiptir. Karayolu projelerinde amaç; yüksek maliyetli sanat yapılarının özellikle çelik köprülerin hizmet ömrünün verimli olması, kaplama tabakasında oluşacak kalıcı ve elastik deformasyonlara karşı en uygun kaplama tipinin seçilmesi ile sürüş kalitesinin ve trafik güvenliğinin en üst seviyede tutulmasıdır. Çelik köprülerde, trafik yüklerinin aşındırıcı etkileri ve tabliyedeki korozyona karşı korumak üzere genellikle mastik asfalt (harç) tipi kaplama tabakası kullanılmaktadır. Bu çalışmada; çelik köprülerde kullanılan üstyapı tiplerinin performanslarının değerlendirilmesi amacıyla; mastik asfalt kaplamalı, mastik asfalt üzeri taş mastik asfalt kaplamalı ve mastik asfalt üzeri modifiye bitümlü aşınma tabakası kaplamalı 3 farklı üstyapı tipinin performansları ölçülmüştür. Çelik tabliyeli köprü üstyapılarında kullanılan karışımlar, taş mastik ve modifiye aşınma tipi karışımlar için Marshall yöntemi ve mastik asfalt için ise ZTV Asphalt StB 07 yöntemi ile hazırlanmış ve karışımlara tekerlek izinde oturma ve yorulma deneyleri yapılarak performansları karşılaştırılmıştır. Our country has a rolling and mountainous terrain as topographicaly. The construction of viaduct and bridges play a significant role with regards to transportation for the route passing through two ridges and sea passages. The main purpose of road and bridge construction projects are to maximize the life expectancy of these high-cost structures and to ensure that the most suitable materials with high resistance against permanent deformations are chosen to improve quality of riding comfort and safety. Steel deck bridge, the mastic asphalt (mortar) type coating layer is used to protect the bridge deck against corrosion by both the corrosive effects of the traffic loads and the corrosion. In this study, the design of the mastic asphalt, stone mastic asphalt and modified bituminous asphalt mixture types used as coating layer in steel bridges. This asphalt mixture were prepared by Marshall and ZTV Asphalt methods and the performances of different bituminous binder types were evaluated by using the wheel traction and fatigue tests.

The technological properties of mastic and sulfur-mastic asphalt concrete mixtures have been evaluated. The hypothesis has been confirmed that the compositions of mastic asphalt concrete mixtures with crystallization-coagulation structure have increased fracture resistance. Optimal technological modes of producing and paving are recommended.

The paper considers the use of crushed stone-mastic asphalt mixtures laid with a small thickness as protective layers of wear of roads. The General characteristics of mixtures and their components are given, the pros and cons, as well as the possibility of their application are given. As a mineral powder, it is recommended to use lime-containing waste (calcium oxide hydrate) of the chemical industry. The effective increase of shear resistance of the protective wear layer with the subsequent prevention of the formation of a track on the coating due to the use of lime-containing waste, which has a highly active structuring effect on bitumen with a slowdown in its aging in the asphalt binder, subject to the principles of sufficient water resistance and crack resistance of asphalt concrete. The replacement of mineral powder with lime-containing waste in the composition of crushed-mastic asphalt concrete with the same mass amount of other mineral components and bitumen indicates a significant increase in quality indicators.

U radu se analizira mogućnost upotrebe reciklirane poliuretanske pjene kao veziva/modifikatora za lijevani asfalt. Rezultati pokazuju da se tvrđi bitumen dobiva s povećanjem poliuretanske pjene do 5 % kada obradivost mješavine postaje nepovoljna. Proizvedena je mješavina lijevanog asfalta s 4 % poliuretanske pjene u bitumenu. Zabilježena je manja vrijednost dubine utiskivanja u usporedbi s uzorkom bez dodataka te je ustanovljeno da se modificirani lijevani asfalt može koristiti na cestama s teškim prometnim opterećenjem. Dobiveni rezultati pokazuju da postoje dobri izgledi za širu primjenu ovog otpadnog polimera., The aim of this paper is to analyse the suitability of recycled polyurethane (PU) foam as a binder modifier in mastic asphalts (MA). The results show that harder bitumen is achieved with an increasing percentage of PU, up to 5 %, when the workability of the sample becomes poor. A MA mix with a 4 % of PU in bitumen was manufactured. A lower indentation was observed when compared to a virgin sample, and it was established that the modified MA can be used on heavy-traffic roads. These results suggest a promising use of this waste polymer.

Pavement rutting is one of the peculiar and far impacting pavement distresses which being observed in flexible pavements. At present, the pavement surface at the bus shelter area appears to be challenging problem and requires maximum attention due to its severe distress, categorized as higher severity rutting. In order to ponder upon such high severity distress, some of the alternative solutions could stand as: Mastic Asphalt (MA), Use of Modified Bitumen, Stone Matrix Asphalt (SMA), White-topping, Glass Fiber Grid, Rigid Pavements and paver-blocks. Thus the overall objective of this study is to explore various alternatives of similar environments and arrive at optimum kind of alternative for Urban Flexible Pavements and also for BRTS Bus Shelters and to evaluate the damage analysis by the use of KENPAVE software of each alternative and compare the cost analysis.

This study aimed at investigating the effect of the floor type used in the walking area of cubicle housing systems and of access to pasture on claw dimensions and claw shape in dairy cows. Data were collected on 36 farms, 12 farms each fitted with mastic asphalt, slatted concrete or solid rubber flooring. With each floor type, cows on half of the farms had access to pasture in summer. The farms were visited three times at intervals of about 6 months and data were collected from 10 cows during each visit. Net growth of the claw horn was highest on rubber flooring and lowest on mastic asphalt. On all floor types, claw angles were larger after the winter period and smaller after the summer period. With regard to claw shape, floor type had an effect on the occurrence of flat, concave and overgrown claw soles. In conclusion, none of the investigated floor types was clearly superior to the others with regard to claw dimensions and claw shape, and access to pasture during summer (median 4 h per day) had only little influence on the investigated claw characteristics.

Multiscale modeling is becoming an increasingly useful method of evaluating the behaviors of asphalt concrete. Reasons for this increased interest include the fact that many of the critical behaviors of this material are affected by localized behaviors that cannot be completely captured using more traditional continuum approaches. Computational methods are popular for this type of evaluation because in principle they can directly account for many of the localized mechanisms. However, computational expense can be excessive, particularly if all of these localized mechanisms are accounted for rigorously. An alternative method of multiscale modeling relying on analytical models is developed and presented in this paper. The model is referred to as the microstructure association model because it accounts for the ways that the multiple scales within asphalt concrete associate together to yield the gross behaviors of the finished composite, asphalt concrete. This model is formed from the hypothesis that a...

V diplomski nalogi so predstavljena področja vgrajevanje lito asfaltne zmesi, ki se danes porablja v tujini in v Sloveniji in kakšna je njegova uporabnost, spremembe v daljšem časovnem obdobju in morebitne napake oziroma poškodbe, ki lahko nastanejo tekom let, in vzroki zanje. Na podlagi zbrane literature s tega področja sem v prvem delu naloge predstavila, kje se liti asfalt vgrajuje v tujini. Ker menim, da se v Sloveniji ne uporablja v tako širokem spektru, bodo v nadaljevanju predstavljena področja vgradnje in izkušenj pri nas. V osrednjem delu sem opisala izkušnje s postopkom proizvodnje in vgrajevanja, vključno s prevozom lito asfaltne zmesi. Vse to zahteva usklajeno oziroma povezano skupino ljudi. Tako delo poteka neprekinjeno, kar je zelo pomembno za kakovost izdelka, je hitro in nenazadnje tudi ekonomično. Na koncu naloge je na konkretnih primerih preverjen kakšen je izgled litega asfalta danes. The thesis presents the areas of installation of mastic asphalt mixture, which nowadays is used in Slovenia and abroad. It describes what is its utility, changes over time, any failure or damage that may arise over the years and the reasons for the changes. In the first part of the thesis subject I present where the mastic asphalt is installed abroad based on the collected literature. Because I believe that in Slovenia it is not applied in such a wide spectrum, I will present the areas of installation and experience in our country in the chapters that follow. In the central part I describe the experience of the production process and the installation, including transport of mastic asphalt mixture. All this requires a coordinated and integrated group of people. Such work is carried out continuously, which is very important for product quality. Such work is also fast and last but not least it is also economical. At the end of the thesis I describe specific cases on the terrain, which show the appearance of asphalt today.

This study assessed the slip resistance of different types of solid flooring in cattle housing using a range of technical tests and gait analysis. Dynamic and static coefficient of friction, skid resistance, and abrasiveness were tested on concrete flooring with a smooth finish, a grooved pattern, or a tamped pattern, acid-resistant mastic asphalt, soft rubber mats, and a worn slatted concrete floor. Coefficients of friction and skid resistance were tested under clean and slurry-soiled conditions. Linear kinematic variables were assessed in 40 cows with trackway measurements after the cows passed over the floors in a straight walk. All gait variables were assessed as deviations from those obtained on the slatted concrete floor, which was used as a baseline. The coefficient of friction tests divided the floors into 3 categories: concrete flooring, which had a low coefficient of friction (0.29-0.41); mastic asphalt flooring, which had medium values (0.38-0.45); and rubber mats, which had high values (0.49-0.57). The highest abrasion (g/10 m) was on the asphalt flooring (4.48), and the concrete flooring with a tamped pattern had significantly higher abrasiveness (2.77) than the other concrete floors (1.26-1.60). Lowest values on the skid-resistance tests (dry/wet) were for smooth concrete (79/35) and mastic asphalt (65/47), especially with a slurry layer on the surface. Gait analysis mainly differentiated floors with higher friction and abrasion by longer strides and better tracking. Step asymmetry was lower on floors with high skid-resistance values. The most secure cow gait, in almost every aspect, was observed on soft rubber mats. Relationships between gait variables and physical floor characteristics ranged from average to weak (partial correlations 0.54-0.16). Thus, none of the physical characteristics alone was informative enough to characterize slip resistance. With reference to gait analysis, the abrasiveness of the hard surfaces was more informative than the coefficient of friction, but the effect of pattern was better detected by skid-resistance measurements. Consequently, several physical characteristics are needed to objectively describe the slip resistance of cattle floors. Soft rubber mats gave better tracking than hard, solid floors, even with a grooved surface or a tamped pattern.

A laboratory investigation of the interactions between granites and asphalts based on rheology is described. In this study of asphalt-filler interactions, the rheological properties of asphalt mastics using different granite powders and different filler-asphalt ratios were measured using a dynamic shear rheometer. Statistically significant relations between the rheological properties of the granite-asphalt mastics and the moisture stability of granite-asphalt mixtures were found. Aggregate factors that influence the moisture stability of asphalt-aggregate mixtures were obtained, and the selection criteria for selecting granite aggregates for use in roads were developed; these could be useful as a reference for practical application.

Weight and pressure distribution on the claw were studied in Swedish Holsteins housed in different flooring systems. A total of 127 cows housed in different sections of the experimental barn were used. Each section had different flooring in the walking and standing areas. There were rubber mats or abrasive mastic asphalt flooring on the alleys or a low-abrasive slatted concrete floor. Some sections had feed-stalls equipped with rubber mats; other sections did not. The vertical ground reaction force, contact area, and average contact pressure were determined on the left hind foot using the I-Scan system and analyzed with the F-scan system. These determinations were made in each of the following 3 zones of the claw: bulb, wall, and sole. Most of the weight on claws exposed to concrete floors was carried by the bulb (37.4 +/- 3.5 and 18.3 +/- 2.9% of weight exerted on the foot in the lateral and medial claw, respectively) and the wall zone (20.0 +/- 2.6 and 13.4 +/- 2.4% on lateral and medial claw, respectively). The weight and pressure distribution in cows kept on sections with rubber covered alleys but passing daily over the asphalt floor on their way to the milking parlor did not differ in any zones, except for lateral bulbs, compared with those exposed to slatted concrete alone. Still, the weight bearing of the sole zone in cows kept on rubber mats without access to asphalt was less than that of cows kept on concrete slatted floors (5.1 +/- 0.7 vs. 12.7 +/- 1.1% and 1.1 +/- 0.5 vs. 8.7 +/- 0.7% in lateral and medial claws, respectively). In cows kept on asphalt flooring without feed-stalls, most weight was exerted to the sole zone (36.2 +/- 2.9 and 22.2 +/- 1.8% in lateral and medial claws, respectively). Feed-stalls in combination with asphalt flooring yielded a decreased total contact area (30.1 +/- 1.2 cm(2)) compared with asphalt floors without feed-stalls (35.7 +/- 1.2 cm(2)). The largest total contact area was obtained on the asphalt floor without feed-stalls, resulting in a lower contact pressure (39.8 +/- 2.3 N/cm(2)) than in claws exposed to concrete (66.0 +/- 2.7 N/ cm(2)) or rubber mats (56.7 +/- 1.7 N/cm(2)). In conclusion, housing with abrasive floors resulted in claws with increased contact area at the sole surface and therefore, decreased contact pressure, but reduced the weight-bearing role of the strongest part of the claw capsule, the claw wall.

The temperatures of pavement of servicing road reach 60 degrees Celsius in summertime. The stiffness of asphalt mixture is often measured by resilient modulus test or uniaxial compression test at normal temperature. But, measurement method at high temperature is not defined. And shape of specimen also influences measured values in such condition. In this research, the measurement of asphalt mixture at high temperature using uniaxial compression test is investigated. As a result, the measurement method and the shape of specimen are proposed and the stiffness characteristics of dense grade asphalt concrete, porous asphalt concrete, stone matrix asphalt concrete and mastic asphalt concrete are measured.

Temperature reduction of mastic asphalt (MA) mixtures can decrease costs and energy demand, as well as health-relevant emissions of particulate matter throughout the life cycle. A state-of-the-art method for temperature reduction is wax modification of the bituminous binder to reduce its viscosity. In this paper, the results of an extensive study. On mechanical performance, particulate matter emission and life-cycle analysis of temperature-reduced MA are presented. Therefore, a reference MA is compared to three temperature-reduced MAs: a state-of-the-art reduction by modification with amide wax (AW) and an alternative method of substituting crushed aggregates by rounded ones. For both methods, a temperature reduction of 30°C can be realised. In addition, a combination of both methods, wax modification and use of rounded aggregates, is investigated. For this combination a reduction of 50°C is possible. The results show that the resistance to permanent deformation is not decreased by using rounded aggregates and that it can be doubled by employing AW regardless of the aggregate shape. Resistance to low-temperature cracking is not affected by any of the studied methods for temperature reduction. Emission analysis reveals that more than 80% of the emitted particulates are below 2.5 µm a.d. (aerodynamic diameter). From a life-cycle perspective, a main benefit of temperature-reduced MAs is the significant decrease in particulate emissions by up to 80% in case of 50°C temperature reduction. Also, up to 20% of production process energy can be saved when the mixing temperature is reduced by 50°C. Application of a wax additive reduces process energy costs, but increases the total life-cycle costs. Based on the considered scenarios, the application of additives is controversial and the substitution of crushed aggregates by rounded aggregates seems to be beneficial.

Currently, in the UK, there is considerable interest in the fact that a German bituminous surfacing mixture known as stone mastic asphalt may possess levels of in-service performance that resist the growing incidence of premature failure experienced by traditional materials such as hot rolled asphalt, A high stone content grading requires the use of a stabilizing additive to ensure long-term performance. The most common type of additive is cellulose fibre, This paper assesses the effect that the addition of differing types of this fibre has on measurable bituminous mix properties.