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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.

Asphalt mastic is known to play an important role when determining the fatigue performance of asphalt mixture. Time sweep test using a Dynamic Shear Rheometer can be used. However, a long testing t...

A laboratory study was done on three bitumen of penetration grade 50/70 from three sources and three corresponding mastics made using these three base bitumen and one filler – Limestone. The tests ...

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.

The 55-km-long Hong Kong–Zhuhai–Macao Bridge (HZMB) is the world’s longest sea-crossing bridge, connecting Hong Kong with Zhuhai and Macao at the mouth of the Pearl River Estuary in China, comprising 22.9-km-long steel bridges. HZMB is the leading steel bridge in China, with top-level manufacturing and installation technology. This paper outlines the steel bridge construction experiences of HZMB to provide comparisons for the construction of other long sea-crossing steel bridges at home or abroad. The main considerations of construction constraints, scheme selection, structural and aesthetic design of HZMB are presented, and the following points related to new strategies in the steel bridge construction of HZMB are elaborated: (1) construction quality assurance, (2) automatic manufacturing technology, (3) large segment offshore installation, (4) eco-friendly paint (content limitation of volatile organic compounds) and new multifunctional inspection gantry, and (5) Guss Mastic Asphalt steel deck pavement system. The successful implementation of those strategies shows that the steel bridge construction of HZMB promotes improvement in the overall construction and management level of the Chinese bridge industry. The advanced experience of HZMB has opened up broad prospects for the design and construction of offshore bridge engineering in China.

Utilisation of recycled construction and demolition waste (CDW) within pavements is a beneficial substitution technique towards sustainability. Following this approach, this research investigates t...

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.

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.

The present study was carried out to evaluate effects of regular sized hydrated lime (RHL) and Nano-sized hydrated lime (NHL) on rutting resistance performance of asphalt mastic related to stiffnes...

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.

The long-term effects of SBS-modified binders and rejuvenators on the properties of high-RAP mixtures, especially the cracking resistance, have not been resolved. Therefore, this paper evaluates th...

Mastic asphalt (MA) is an important construction material mainly used for infrastructure pavements as well as industrial and garage floors. As mastic asphalt construction sites are often limited in space, the prevalent form of construction is by manual paving. Therefore, the emissions caused by mastic asphalt are not only relevant for the environment, but also highly relevant for workers' health. In this study, we examine four mastic asphalt mixtures in terms of their emissions and worker exposure at various construction temperatures, ranging from 195 °C to 245 °C. We conducted three laboratory studies and a field study to evaluate the emissions away from the construction site, emissions in close proximity to the construction site, direct worker exposure and, for the very first time, also the absolute emissions in mass PM10 a.d. per mass of MA. The experiments show that a big part (80 wt%) of the PM10 a.d. emissions consists of particles smaller than 0.8 μm a.d. and are therefore very health relevant. Furthermore, we could show consistently in all our experiments that decreasing the paving temperature by 50 °C (by using a MA mixture workable below 200 °C) leads to an emission reduction of up to 70%.

The present study evaluates effects of regular sized hydrated lime (RHL) and nano sized hydrated lime (NHL) on fatigue and bond strength of asphalt mastic. The asphalt mastics were produced in the laboratory using AC-30 binder with different combinations of basalt–RHL, and basalt–NHL fillers. The dosages of RHL and NHL were selected as 0%, 5%, 10%, 15%, and 20% by weight of asphalt binder, and the percentage of basalt filler was adjusted accordingly. Filler to binder (F/B) ratio was selected as 0.8 (by mass ratio) for all mastic sample preparation. The fatigue damage behavior (number of cycles to fatigue damage/failure) of asphalt mastic was evaluated using a linear amplitude sweep (LAS) test. Further, the interfacial bond strengths of asphalt mastic and aggregate samples were evaluated using the bitumen bond strength (BBS) test. Overall test results indicate that mineralogy, surface area, and interaction properties of RHL and NHL fillers have a significant effect on fatigue, bond strength, and moisture damage performance of asphalt mastic. The results from the LAS test showed that NHL filler predominantly enhanced the fatigue life of asphalt mastic as compared with RHL filler. BBS test results imply that the contribution of NHL filler is significant over RHL filler in improving the bond strength and moisture damage resistance of asphalt mastic. Overall asphalt mastic with 20% NHL filler had better fatigue life, bond strength, and moisture damage performance over mastic with other percentages of RHL or NHL fillers.

In this study, a modified asphalt based trackless tack coat material (TTCM) was prepared by adding styrene–butadiene–styrene, uintaite mastic asphalt, anti-rut asphalt master batch and Sasobit wax to 50# base asphalt (penetration grade). Mehcnaimcal properties like track resistance, shear strength, pull-off strength, and rheological as well as temperature performance of TTCM were studied. Results showed that the adhesive bond strength of TTCM was greater than cohesive forces within hot mix asphalt layer, track-free time was less than 1 min and it did not deteriorate upon contact with tyres at 60 °C. Furthermore, bonding mechanism of TTCM was proposed. Surface morphology and functional group characterization were achieved using SEM and FTIR, respectively. The present approach utilizing routine raw materials and ease of operation for the synthesis of novel modified asphalt based TTCM with enhanced performance can be effectively applied on industrial level production for practical applications.

This paper presents the self-healing results of asphalt mastic by the action of calcium-alginate capsules containing sunflower oil. The morphological, physical, thermal and mechanical properties of the capsules have been evaluated. Additionally, the effect of the capsule oil content and the healing temperature on the self-healing properties of asphalt mastic have been evaluated. It was proven that the capsules can resist the mixing and compaction processes and break inside the asphalt mastic due to mechanical loads, releasing the oil. Healing levels in the asphalt mastic samples with capsules were greater than samples without capsules. The healing level depended on the oil content of the capsules and temperature.