Search results for: asphalt ridge
262 Getting to Know the Types of Asphalt, Its Manufacturing and Processing Methods and Its Application in Road Construction
Authors: Hamid Fallah
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Asphalt is generally a mixture of stone materials with continuous granulation and a binder, which is usually bitumen. Asphalt is made in different shapes according to its use. The most familiar type of asphalt is hot asphalt or hot asphalt concrete. Stone materials usually make up more than 90% of the asphalt mixture. Therefore, stone materials have a significant impact on the quality of the resulting asphalt. According to the method of application and mixing, asphalt is divided into three categories: hot asphalt, protective asphalt, and cold asphalt. Cold mix asphalt is a mixture of stone materials and mixed bitumen or bitumen emulsion whose raw materials are mixed at ambient temperature. In some types of cold asphalt, the bitumen may be heated as necessary, but other materials are mixed with the bitumen without heating. Protective asphalts are used to make the roadbed impermeable, increase its abrasion and sliding resistance, and also temporarily improve the existing asphalt and concrete surfaces. This type of paving is very economical compared to hot asphalt due to the speed and ease of implementation and the limited need for asphalt machines and equipment. The present article, which is prepared in descriptive library form, introduces asphalt, its types, characteristics, and its application.Keywords: asphalt, type of asphalt, asphalt concrete, sulfur concrete, bitumen in asphalt, sulfur, stone materials
Procedia PDF Downloads 57261 Characteristics of Asphalt Mixtures with Cocoa Shell Ash as Filler
Authors: Muhammad Nur Hidayat, Muksalmina, Chairul Fajar
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An alternative to improve the quality of asphalt as a pavement material is to use modified asphalt with the addition of cocoa shell ash as a filler. This research aims to determine the effect of asphalt mixture and cocoa shell ash after testing the physical properties of asphalt. The method used was experimental by testing the physical properties of asphalt. The results showed that the optimum asphalt content of the cocoa husk ash mixture was 2%, with an asphalt penetration value of 60.03 mm. The result of the asphalt softening point test was 51.0°C. Asphalt ductility test results in 144 cm. Asphalt specific gravity test result 1.076 gr/ml. Asphalt weight loss test results in 0.0183%. In conclusion, cocoa shell ash has an effect on asphalt characteristics, namely increasing stability, flexibility and fatigue resistance.Keywords: cocoa husk ash, asphalt characteristics, physical properties testing, filler
Procedia PDF Downloads 24260 Physicochemical Characterization of Asphalt Ridge Froth Bitumen
Authors: Nader Nciri, Suil Song, Namho Kim, Namjun Cho
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Properties and compositions of bitumen and bitumen-derived liquids have significant influences on the selection of recovery, upgrading and refining processes. Optimal process conditions can often be directly related to these properties. The end uses of bitumen and bitumen products are thus related to their compositions. Because it is not possible to conduct a complete analysis of the molecular structure of bitumen, characterization must be made in other terms. The present paper focuses on physico-chemical analysis of two different types of bitumens. These bitumen samples were chosen based on: the original crude oil (sand oil and crude petroleum), and mode of process. The aim of this study is to determine both the manufacturing effect on chemical species and the chemical organization as a function of the type of bitumen sample. In order to obtain information on bitumen chemistry, elemental analysis (C, H, N, S, and O), heavy metal (Ni, V) concentrations, IATROSCAN chromatography (thin layer chromatography-flame ionization detection), FTIR spectroscopy, and 1H NMR spectroscopy have all been used. The characterization includes information about the major compound types (saturates, aromatics, resins and asphaltenes) which can be compared with similar data for other bitumens, more importantly, can be correlated with data from petroleum samples for which refining characteristics are known. Examination of Asphalt Ridge froth bitumen showed that it differed significantly from representative petroleum pitches, principally in their nonhydrocarbon content, heavy metal content and aromatic compounds. When possible, properties and composition were related to recovery and refining processes. This information is important because of the effects that composition has on recovery and processing reactions.Keywords: froth bitumen, oil sand, asphalt ridge, petroleum pitch, thin layer chromatography-flame ionization detection, infrared spectroscopy, 1H nuclear magnetic resonance spectroscopy
Procedia PDF Downloads 419259 Age and Sex Identification among Egyptian Population Using Fingerprint Ridge Density
Authors: Nazih Ramadan, Manal Mohy-Eldine, Amani Hanoon, Alaa Shehab
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Background and Aims: The study of fingerprints is widely used in providing a clue regarding identity. Age and gender identification from fingerprints is an important step in forensic anthropology in order to minimize the list of suspects search. The aim of this study was to determine finger ridge density and patterns among Egyptians, and to estimate age and gender using ridge densities. Materials and Methods: This study was conducted on 177 randomly-selected healthy Egyptian subjects (90 males and 87 females). They were divided into three age groups; Group (a): from 6-< 12 years, group (b) from 12-< 18 years and group (c) ≥ 18 years. Bilateral digital prints, from every subject, were obtained by the inking procedure. Ridge count per 25 mm² was determined together with assessment of ridge pattern type. Statistical analysis was done with references to different age and sex groups. Results: There was a statistical significant difference in ridge density between the different age groups; where younger ages had significantly higher ridge density than older ages. Females proved to have significantly higher ridge density than males. Also, there was a statistically significant negative correlation between age and ridge density. Ulnar loops were the most frequent pattern among Egyptians then whorls then arches then radial loops. Finally, different regression models were constructed to estimate age and gender from fingerprints ridge density. Conclusion: fingerprint ridge density can be used to identify both age and sex of subjects. Further studies are recommended on different populations, larger samples or using different methods of fingerprint recording and finger ridge counting.Keywords: age, sex identification, Egyptian population, fingerprints, ridge density
Procedia PDF Downloads 355258 Optimization of Carbon Nanotube Content of Asphalt Nanocomposites with Regard to Resistance to Permanent Deformation
Authors: João V. Staub de Melo, Glicério Trichês, Liseane P. Thives
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This paper presents the results of the development of asphalt nanocomposites containing carbon nanotubes (CNTs) with high resistance to permanent deformation, aiming to increase the performance of asphalt surfaces in relation to the rutting problem. Asphalt nanocomposites were prepared with the addition of different proportions of CNTs (1%, 2% and 3%) in relation to the weight of asphalt binder. The base binder used was a conventional binder (50-70 penetration) classified as PG 58-22. The optimum percentage of CNT addition in the asphalt binder (base) was determined through the evaluation of the rheological and empirical characteristics of the nanocomposites produced. In order to evaluate the contribution and the effects of the nanocomposite (optimized) in relation to the rutting, the conventional and nanomodified asphalt mixtures were tested in a French traffic simulator (Orniéreur). The results obtained demonstrate the efficient contribution of the asphalt nanocomposite containing CNTs to the resistance to permanent deformation of the asphalt mixture.Keywords: asphalt nanocomposites, asphalt mixtures, carbon nanotubes, nanotechnology, permanent deformation
Procedia PDF Downloads 279257 Review of Research on Waste Plastic Modified Asphalt
Authors: Song Xinze, Cai Kejian
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To further explore the application of waste plastics in asphalt pavement, this paper begins with the classification and characteristics of waste plastics. It then provides a state-of-the-art review of the preparation methods and processes of waste plastic modifiers, waste plastic-modified asphalt, and waste plastic-modified asphalt mixtures. The paper also analyzes the factors influencing the compatibility between waste plastics and asphalt and summarizes the performance evaluation indicators for waste plastic-modified asphalt and its mixtures. It explores the research approaches and findings of domestic and international scholars and presents examples of waste plastics applications in pavement engineering. The author believes that there is a basic consensus that waste plastics can improve the high-temperature performance of asphalt. The use of cracking processes to solve the storage stability of waste plastic polymer-modified asphalt is the key to promoting its application. Additionally, the author anticipates that future research will concentrate on optimizing the recycling, processing, screening, and preparation of waste plastics, along with developing composite plastic modifiers to improve their compatibility and long-term performance in asphalt pavements.Keywords: waste plastics, asphalt pavement, asphalt performance, asphalt modification
Procedia PDF Downloads 29256 Estimation of Coefficients of Ridge and Principal Components Regressions with Multicollinear Data
Authors: Rajeshwar Singh
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The presence of multicollinearity is common in handling with several explanatory variables simultaneously due to exhibiting a linear relationship among them. A great problem arises in understanding the impact of explanatory variables on the dependent variable. Thus, the method of least squares estimation gives inexact estimates. In this case, it is advised to detect its presence first before proceeding further. Using the ridge regression degree of its occurrence is reduced but principal components regression gives good estimates in this situation. This paper discusses well-known techniques of the ridge and principal components regressions and applies to get the estimates of coefficients by both techniques. In addition to it, this paper also discusses the conflicting claim on the discovery of the method of ridge regression based on available documents.Keywords: conflicting claim on credit of discovery of ridge regression, multicollinearity, principal components and ridge regressions, variance inflation factor
Procedia PDF Downloads 410255 Effect of Rubber Tyre and Plastic Wastes Use in Asphalt Concrete Pavement
Authors: F. Onyango, Salim R. Wanjala, M. Ndege, L. Masu
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Asphalt concrete pavements have a short life cycle, failing mainly due to temperature changes, traffic loading and ageing. Modified asphalt mixtures provide the technology to produce a bituminous binder with improved viscoelastic properties which remain in balance over a wider temperature range and loading conditions. In this research, 60/70 penetration grade asphalt binder was modified by adding 2, 4, 6, 8, and 10 percent by weight of asphalt binder following the wet process and the mineral aggregate was modified by adding 1, 2, 3, 4, and 5 percent crumb rubber by volume of the mineral aggregate following the dry process. The LDPE modified asphalt binder Rheological properties were evaluated. The laboratory results showed an increase in viscosity, softening point and stiffness of the binder. The modified asphalt was then used in preparing asphalt mixtures by Marshall Mix design procedure. The Marshall stability values for mixes containing 2% crumb rubber and 4% LDPE were found to be 30% higher than the conventional asphalt concrete mix.Keywords: crumb rubber, dry process, hot mix asphalt, wet process
Procedia PDF Downloads 363254 Evaluation of Ultrasonic Techniques for the Estimation of Air Voids in Asphalt Concrete
Authors: Majid Zargar, Frank Bullen, Ron Ayers
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One of the important factors in the design of asphalt concrete mixes is the accurate measurement of air voids and their variable distribution. Both can have significant impact on long and short term fatigue and creep behaviour under traffic. While some simple methods exist for overall evaluation of air voids, measuring air void distribution in asphalt concrete is very complex, involving expensive techniques such as X-ray methodologies. The research reported in the paper investigated the use of non-destructive ultrasonic techniques as an alternative to estimate the amount of air voids and their distribution within asphalt samples. Seventy-four Standard AC–14 asphalt samples made with three types of bitumen; Multigrade, PMB and C320 were analysed using ultrasonic techniques. The results have illustrated that ultrasonic testing has the potential of being a rapid, accurate and cost-effective method of estimating air void distribution in asphalt.Keywords: asphalt concrete, air voids, ultrasonic, mechanical behaviour
Procedia PDF Downloads 340253 Investigating the Properties of Asphalt and Asphalt Mixture Based on the Effect of Waste Toner
Authors: Prince Igor Itoua, Daquan Sun, Shihui Shen
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This study aimed at investigating the properties of asphalt and mix asphalt based on the effects of waste toner sources (WT1 and WT2) with 8% dosage waste toner powders (WT). The test results included penetration, softening points, ductility, G*sinδ, G*/sinδ, Ideal cracking test(IDEAL-CT), and Ideal shear rutting test(IDEAL-RT). The results showed that the base binder with WT2 had a significantly higher viscosity value compared to the WT1 modified binder, and thus, higher energy for mixing and compaction is needed. Fur-thermore, the results of penetration, softening points, G*sinδ, and G*/sinδ were all affected by waste toner type. In terms of asphalt mixture, the IDEAL-RT test revealed that the addition of waste toner improved the rutting resistance of the asphalt mixture regardless of toner type. Further, CTindex values for waste toner-modified asphalt mixtures show no significant difference. Above all, WT-modified asphalt mixtures produced by the wet process have better rutting performance.Keywords: waste toner, waste toner modified asphalt, asphalt mixture properties, IDEAL-RT test, IDEAL-CT test
Procedia PDF Downloads 76252 A Study on Fatigue Performance of Asphalt Using AMPT
Authors: Yuan Jie Kelvin Lu, Amin Chegenizadeh
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Asphalt pavement itself is a mixture made up of mainly aggregates, binders, and fillers that acts as a composition used for pavement construction. An experimental program was setup to determine the fatigue performance test of Asphalt with three different grades of conventional binders. Asphalt specimen has achieved the maximum optimum bulk density and air voids with a consistent bulk density of 2.3 t/m3, with an air void of 5% ± 0.5, before loading into the Asphalt Mixture Performance Tested (AMPT) for fatigue test. The number of cycles is defined as the point where phase angle drops, which is caused by the formation of cracks due to the increasing micro cracks when asphalt is undergoing repeated cycles of loading. Thus, the data collected are analyzed using the drop of phase angle as failure criteria. Based in the data analyzed, it is evident that the fatigue life of asphalt lies on the grade of binder. The result obtained shows that all specimens do experience a drop in phase angle due to macro cracks in the asphalt specimen.Keywords: asphalt binder, AMPT, CX test, simplified – viscoelastic continuum damage (S-VECD)
Procedia PDF Downloads 346251 Comparison of Rheological Properties for Polymer Modified Asphalt Produced in Riyadh
Authors: Ali M. Babalghaith, Hamad A. Alsoliman, Abdulrahman S. Al-Suhaibani
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Flexible pavement made with neat asphalt binder is not enough to resist heavy traffic loads as well as harsh environmental condition found in Riyadh region. Therefore, there is a need to modify asphalt binder with polymers to satisfy such conditions. There are several types of polymers that are used to modify asphalt binder. The objective of this paper is to compare the rheological properties of six polymer modified asphalt binders (Lucolast7010, Anglomak2144, Paveflex140, SBS KTR401, EE-2 and Crumb rubber) obtained from asphalt manufacturer plants. The rheological properties of polymer modified asphalt binders were tested using conventional tests such as penetration, softening point and viscosity; and SHRP tests such as dynamic shear rheometer and bending beam rheometer. The results have indicated that the polymer modified asphalt binders have lower penetration and higher softening point than neat asphalt indicating an improvement in stiffness of asphalt binder, and as a result, more resistant to rutting. Moreover, the dynamic shear rheometer results have shown that all modifiers used in this study improved the binder properties and satisfied the Superpave specifications except SBS KTR401 which failed to satisfy the rutting parameter (G*/sinδ).Keywords: polymer modified asphalt, rheological properties, SBS, crumb rubber, EE-2
Procedia PDF Downloads 279250 Laboratory Evaluation of Rutting and Fatigue Damage Resistance of Asphalt Mixtures Modified with Carbon Nano Tubes
Authors: Ali Zain Ul Abadeen, Arshad Hussain
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Roads are considered as the national capital, and huge developmental budget is spent on its construction, maintenance, and rehabilitation. Due to proliferating traffic volume, heavier loads and challenging environmental factors, the need for high-performance asphalt pavement is increased. In this research, the asphalt mixture was modified with carbon nanotubes ranging from 0.2% to 2% of binder to study the effect of CNT modification on rutting potential and fatigue life of asphalt mixtures. During this study, the conventional and modified asphalt mixture was subjected to a uni-axial dynamic creep test and dry Hamburg wheel tracking test to study rutting resistance. Fatigue behavior of asphalt mixture was studied using a four-point bending test apparatus. The plateau value of asphalt mixture was taken as a measure of fatigue performance according to the ratio of dissipated energy approach. Results of these experiments showed that CNT modified asphalt mixtures had reduced rut depth and increased rutting and fatigue resistance at higher percentages of carbon nanotubes.Keywords: carbon nanotubes, fatigue, four point bending test, modified asphalt, rutting
Procedia PDF Downloads 135249 Study of Ladle Furnace Slag as Mineral Filler in Asphalt Concrete with Electric Arc Furnace Slag
Authors: W. J. Wang, D. F. Lin, L. Y. Chen, K. Y. Liu
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In this study, the ladle furnace slag was used as a mineral filler in asphalt concrete with electric arc furnace slag (EAF asphalt concrete) to investigate the effect on the engineering and thermal properties of asphalt cement mastics and EAF asphalt concrete, the lime was used as a comparison for mineral filler, and the usage percentage of mineral filler was set at 2%, 4%, 6%, and 8%. First of all, the engineering properties of the ladle furnace slag and lime were compared, and then the mineral filler was mixed with bitumen to form the asphalt cement mastics in order to analyze the influence of the ladle furnace slag on the properties of asphalt cement mastics, and lastly, the mineral filler was used in the EAF asphalt concrete to analyze its feasibility of using ladle furnace slag as a mineral filler. The study result shows that the ladle furnace slag and the lime have no obvious difference in their physical properties, and from the energy dispersive spectrometer (EDS) test results, we know that the lime and the ladle furnace slag have similar elemental composition, but the Ca found in the ladle furnace slag belongs to CaO, and the lime belongs to CaCO3, therefore the ladle furnace slag has the property of expansion. According to the test results, the viscosity of asphalt cement mastics will increase with the increase in the use of mineral filler. Since the ladle furnace slag has more CaO content, the viscosity of the asphalt cement mastics with ladle furnace slag will increase more than using lime as mineral filler in the asphalt cement mastics, and the use of ladle furnace slag only needs to be 2% in order to achieve the effect of anti-peeling which is 6% for lime. From the related test results of EAF asphalt concrete, it is known that the maximum stability value can be obtained when the use of mineral filler is about 5%. When the ladle furnace slag is used as the mineral filler, it can improve the stiffness, indirect tension strength, spalling resistance, and thermal insulation of EAF asphalt concrete, which also indicates that using the ladle furnace slag as the mineral filler of bitumen can help to improve the durability of the asphalt pavement.Keywords: ladle furnace slag, mineral filler, asphalt cement mastics, EAF asphalt concrete
Procedia PDF Downloads 74248 Recycled Asphalt Pavement with Warm Mix Additive for Sustainable Road Construction
Authors: Meor Othman Hamzah, Lillian Gungat, Nur Izzi Md. Yusoff, Jan Valentin
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The recent hike in raw materials costs and the quest for preservation of the environment has prompted asphalt industries to adopt greener road construction technology. This paper presents a study on such technology by means of asphalt recycling and use of warm mix asphalt (WMA) additive. It evaluates the effects of a WMA named RH-WMA on binder rheological properties and asphalt mixture performance. The recycled asphalt, obtained from local roads, was processed, fractionated, and incorporated with virgin aggregate and binder. For binder testing, the recycled asphalt was extracted and blended with virgin binder. The binder and mixtures specimen containing 30 % and 50 % recycled asphalt contents were mixed with 3 % RH-WMA. The rheological properties of the binder were evaluated based on fundamental, viscosity, and frequency sweep tests. Indirect tensile strength and resilient modulus tests were carried out to assess the mixture’s performances. The rheological properties and strength performance results showed that the addition of RH-WMA slightly reduced the binder and mixtures stiffness. The percentage of recycled asphalt increased the stiffness of binder and mixture, and thus improves the resistance to rutting. Therefore, the integration of recycled asphalt and RH-WMA can be an alternative material for road sustainable construction for countries in the tropics.Keywords: recycled asphalt, warm mix additive, rheological, mixture performance
Procedia PDF Downloads 508247 Development of Recycled-Modified Asphalt Using Basalt Aggregate
Authors: Dong Wook Lee, Seung Hyun Kim, Jeongho Oh
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With the strengthened regulation on the mandatory use of recycled aggregate, development of construction materials using recycled aggregate has recently increased. This study aimed to secure the performance of asphalt concrete mixture by developing recycled-modified asphalt using recycled basalt aggregate from the Jeju area. The strength of the basalt aggregate from the Jeju area used in this study was similar to that of general aggregate, while the specific surface area was larger due to the development of pores. Modified asphalt was developed using a general aggregate-recycled aggregate ratio of 7:3, and the results indicated that the Marshall stability increased by 27% compared to that of asphalt concrete mixture using only general aggregate, and the flow values showed similar levels. Also, the indirect tensile strength increased by 79%, and the toughness increased by more than 100%. In addition, the TSR for examining moisture resistance was 0.95 indicating that the reduction in the indirect tensile strength due to moisture was very low (5% level), and the developed recycled-modified asphalt could satisfy all the quality standards of asphalt concrete mixture.Keywords: asphalt concrete mixture, performance grade, recycled basalt aggregate, recycled-modified asphalt
Procedia PDF Downloads 351246 A Molecular-Level Study of Combining the Waste Polymer and High-Concentration Waste Cooking Oil as an Additive on Reclamation of Aged Asphalt Pavement
Authors: Qiuhao Chang, Liangliang Huang, Xingru Wu
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In the United States, over 90% of the roads are paved with asphalt. The aging of asphalt is the most serious problem that causes the deterioration of asphalt pavement. Waste cooking oils (WCOs) have been found they can restore the properties of aged asphalt and promote the reuse of aged asphalt pavement. In our previous study, it was found the optimal WCO concentration to restore the aged asphalt sample should be in the range of 10~15 wt% of the aged asphalt sample. After the WCO concentration exceeds 15 wt%, as the WCO concentration increases, some important properties of the asphalt sample can be weakened by the addition of WCO, such as cohesion energy density, surface free energy density, bulk modulus, shear modulus, etc. However, maximizing the utilization of WCO can create environmental and economic benefits. Therefore, in this study, a new idea about using the waste polymer is another additive to restore the WCO modified asphalt that contains a high concentration of WCO (15-25 wt%) is proposed, which has never been reported before. In this way, both waste polymer and WCO can be utilized. The molecular dynamics simulation is used to study the effect of waste polymer on properties of WCO modified asphalt and understand the corresponding mechanism at the molecular level. The radial distribution function, self-diffusion, cohesion energy density, surface free energy density, bulk modulus, shear modulus, adhesion energy between asphalt and aggregate are analyzed to validate the feasibility of combining the waste polymer and WCO to restore the aged asphalt. Finally, the optimal concentration of waste polymer and WCO are determined.Keywords: reclaim aged asphalt pavement, waste cooking oil, waste polymer, molecular dynamics simulation
Procedia PDF Downloads 208245 Thermo-Oxidative Degradation of Asphalt Modified with High Density Polyethylene and Engine Oil
Authors: Helder Shelton Abel Manguene, Giovanna Buonocore, Herminio Francisco Muiambo
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Paved roads are designed for 10-15 years of life. However, many asphalted roads suffer degradation before reaching their lifetime due to aging caused by load conditions and climatic factors. Oxidation is the main asphalt aging mechanism, which leads to a reduced bond between aggregate particles, increasing the potential for stripping and moisture damage, decreasing fatigue lifetime and reducing resistance to thermal cracking. To improve the performance of asphalt and mitigate these problems, modifiers such as polymers, oils and certain residues have been used. This work aims to study the influence of the addition of high-density polyethylene (HDPE) and engine oil on the thermal stability of asphalt in an oxidizing atmosphere. For the study, compositions containing asphalt, motor oil and HDPE were prepared, varying the concentration of the motor oil by 2.5%, 5%, 7.5% and 10% and keeping the HDPE concentration fixed at 5%. The results show that the pure asphalt sample is degraded in a single step that starts at approximately 311 ºC; All samples of modified asphalt except the one that contains 5% of motor oil have three degradation steps that start below the starting temperature of degradation of pure asphalt (about 250-300 ºC); The temperature of onset of degradation of the modified asphalt is shown to decrease as the concentration of the motor oil increases, suggesting a slight loss of thermal stability of the asphalt as the quantity of the motor oil increases.Keywords: Asphalt, DTG, engine oil, HDPE, TGA
Procedia PDF Downloads 205244 Effect of Nano-Alumina on the Mechanical Properties of Cold Recycled Asphalt
Authors: Shahab Hasani Nasab, Aran Aeini, Navid Kermanshahi
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In order to reduce road building costs and reduce environmental damage, recycled materials can be used instead of mineral materials in the production of asphalt mixtures. Today, in most parts of the world, cold recycled asphalt with bitumen emulsion, has acceptable results. However, Cold Recycled Asphalt have some deficiency such as stripping, thermal cracking, and rutting. This requires the addition of additives to reduce this deficiency of recycled pavement with emulsified asphalt. In this research, nano-alumina and emulsified asphalt were used to modify the properties of recycled asphalt mixtures according to the technical specifications and the operation of cold recycling. Marshall test methods, dynamic creep test, and resiliency modulus test has been used to obtain the nano-alumina’s effects on asphalt mixture properties. The results show that the addition of nano-alumina would reduce the Marshall stability in samples but increases the rutting resistance. The resiliency modulus increases significantly with this additive.Keywords: cold asphalt, cold recycling, nano-alumina, dynamic creep, bitumen emulsion
Procedia PDF Downloads 157243 Influence of the Quality Differences in the Same Type of Bitumen and Dosage Rate of Reclaimed Asphalt on Lifetime
Authors: Pahirangan Sivapatham, , Esser Barbara
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The impacts of the asphalt mix design, the properties of aggregates and quality differences in the same type of bitumen, as well as the dosage rate of reclaimed asphalt on the relevant material parameter of the analytical pavement design method are not known. Due to that, in this study, the influence of the above mentioned characteristics on relevant material parameters has been determined and analyzed by means of the analytical pavement calculations method. Therefore, material parameters for several asphalt mixes for asphalt wearing course, asphalt binder course and asphalt base course have been determined. Thereby several bitumens of the same type from different producer’s have been used. In addition, asphalt base course materials with three different dosages of reclaimed asphalt have been produced and tested. As material parameter according to the German analytical pavement design guide(RDO Asphalt), the stiffness’s at different temperatures and fatigue behavior have been determined. The findings of asphalt base course materials produced with several pen graded bitumen from different producers and different dosages of reclaimed asphalt indicate the distinct impact on fatigue behaviors and mechanical properties. The calculated test results of the analytical pavement design method show significant differences in the lifetimes. The pavement design calculation is to carry out by means of the actual material parameter. The calculated lifetime of the asphalt base course materials differentiates by the factor 3.2. The determining test results of bitumen characteristics meet the requirement according to the German Standards. But, further investigations of bitumen in different aging conditions show significant differences in their quality. The fatigue behavior and stiffness of asphalt pavement improves with increasing dosage of reclaimed asphalt. Furthermore, the type of aggregates used shows no significant influences.Keywords: reclaimed asphalt pavement, quality differences in the bitumen, life time calculation, Asphalt mix with RAP
Procedia PDF Downloads 178242 The Influence of Moisture Conditioning on Hamburg Wheel Tracking Test Results
Authors: Hussain Al-Baghli
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The Hamburg Wheel Tracking Test (HWTT) was conducted to evaluate the resistance to moisture damage of two asphalt mixtures: an optimized rubberized asphalt mixture and an HMA mix with anti-stripping additives. The mixtures were subjected to varying numbers of moisture conditioning cycles and then tested for rutting depth. The results showed that the optimized rubberized asphalt mixture met the requirements for medium to heavy traffic in accordance with Kuwait's Ministry of Public Works specification. The number of moisture conditioning cycles did not significantly impact rutting development for the rubberized asphalt. The HMA asphalt samples showed a significant reduction in strength and did not satisfy the HWTT criteria after the moisture conditioning cycles.Keywords: rubberized asphalt, Hamburg wheel tracking, antistripping, moisture conditioning
Procedia PDF Downloads 68241 Environmental Potentials within the Production of Asphalt Mixtures
Authors: Florian Gschösser, Walter Purrer
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The paper shows examples for the (environmental) optimization of production processes for asphalt mixtures applied for typical road pavements in Austria and Switzerland. The conducted “from-cradle-to-gate” LCA firstly analyzes the production one cubic meter of asphalt and secondly all material production processes for exemplary highway pavements applied in Austria and Switzerland. It is shown that environmental impacts can be reduced by the application of reclaimed asphalt pavement (RAP) and by the optimization of specific production characteristics, e.g. the reduction of the initial moisture of the mineral aggregate and the reduction of the mixing temperature by the application of low-viscosity and foam bitumen. The results of the LCA study demonstrate reduction potentials per cubic meter asphalt of up to 57 % (Global Warming Potential–GWP) and 77 % (Ozone depletion–ODP). The analysis per square meter of asphalt pavement determined environmental potentials of up to 40 % (GWP) and 56 % (ODP).Keywords: asphalt mixtures, environmental potentials, life cycle assessment, material production
Procedia PDF Downloads 524240 Best Timing for Capturing Satellite Thermal Images, Asphalt, and Concrete Objects
Authors: Toufic Abd El-Latif Sadek
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The asphalt object represents the asphalted areas like roads, and the concrete object represents the concrete areas like concrete buildings. The efficient extraction of asphalt and concrete objects from one satellite thermal image occurred at a specific time, by preventing the gaps in times which give the close and same brightness values between asphalt and concrete, and among other objects. So that to achieve efficient extraction and then better analysis. Seven sample objects were used un this study, asphalt, concrete, metal, rock, dry soil, vegetation, and water. It has been found that, the best timing for capturing satellite thermal images to extract the two objects asphalt and concrete from one satellite thermal image, saving time and money, occurred at a specific time in different months. A table is deduced shows the optimal timing for capturing satellite thermal images to extract effectively these two objects.Keywords: asphalt, concrete, satellite thermal images, timing
Procedia PDF Downloads 313239 Synthesis of Telechelic Polymers for Asphalt Pavements
Authors: Paula C Arroyo, Norma A Sánchez, Mikhail Tlenkopatchev
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The continuous growth in population has resulted in an increment in road construction. The road construction requires more lasting and resistant pavements. Among the different applications of polymers, the reinforcement of pavements throw the modification of asphalt has demonstrated to be an area of special interest for new polymers. The modified asphalt should exhibit a considerable good performance, good elastic properties and an increment in the performance grade (PG). Some of the current polymers used in asphalt are styrene butadiene styrene (SBS), poly(n-butyl methacrylate)-(glycidyl methacrylate) and ethylene-vinyl acetate EVA. The goal of this study was to synthesize low molecular weight (2,000 – 150,000 D) telechelic polymers to be applied at low concentrations in asphalt in order to modify its rheological properties and make it more resistant and durable. The telechelic polymers were obtained from different molar relationships between tensioned and functionalized olefins by ring opening metathesis polymerization (ROMP) and cross metathesis (CR). The synthesis was carried out under inert conditions with Grubbs second generation catalyst. The reaction efficiency was superior to 96% and telechelic polymers were characterized. The telechelic polymers were used to modify asphalt and the rheological properties of the modified asphalt were evaluated finding that at low concentrations (1%) the PG increased in one or two degrees.Keywords: asphalt polymers, metathesis polymers, telechelic polymers, modified asphalt
Procedia PDF Downloads 266238 Clinical Efficacy of Indigenous Software for Automatic Detection of Stages of Retinopathy of Prematurity (ROP)
Authors: Joshi Manisha, Shivaram, Anand Vinekar, Tanya Susan Mathews, Yeshaswini Nagaraj
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Retinopathy of prematurity (ROP) is abnormal blood vessel development in the retina of the eye in a premature infant. The principal object of the invention is to provide a technique for detecting demarcation line and ridge detection for a given ROP image that facilitates early detection of ROP in stage 1 and stage 2. The demarcation line is an indicator of Stage 1 of the ROP and the ridge is the hallmark of typically Stage 2 ROP. Thirty Retcam images of Asian Indian infants obtained during routine ROP screening have been used for the analysis. A graphical user interface has been developed to detect demarcation line/ridge and to extract ground truth. This novel algorithm uses multilevel vessel enhancement to enhance tubular structures in the digital ROP images. It has been observed that the orientation of the demarcation line/ridge is normal to the direction of the blood vessels, which is used for the identification of the ridge/ demarcation line. Quantitative analysis has been presented based on gold standard images marked by expert ophthalmologist. Image based analysis has been based on the length and the position of the detected ridge. In image based evaluation, average sensitivity and positive predictive value was found to be 92.30% and 85.71% respectively. In pixel based evaluation, average sensitivity, specificity, positive predictive value and negative predictive value achieved were 60.38%, 99.66%, 52.77% and 99.75% respectively.Keywords: ROP, ridge, multilevel vessel enhancement, biomedical
Procedia PDF Downloads 395237 Design of a Laboratory Test for InvestigatingPermanent Deformation of Asphalt
Authors: Esmaeil Ahmadinia, Frank Bullen, Ron Ayers
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Many concerns have been raised in recent years about the adequacy of existing creep test methods for evaluating rut-resistance of asphalt mixes. Many researchers believe the main reason for the creep tests being unable to duplicate field results is related to a lack of a realistic confinement for laboratory specimens. In-situ asphalt under axle loads is surrounded by a mass of asphalt, which provides stress-strain generated confinement. However, most existing creep tests are largely unconfined in their nature. It has been hypothesised that by providing a degree of confinement, representative of field conditions, in a creep test, it could be possible to establish a better correlation between the field and laboratory. In this study, a new methodology is explored where confinement for asphalt specimens is provided. The proposed methodology is founded on the current Australian test method, adapted to provide simulated field conditions through the provision of sample confinement.Keywords: asphalt mixture, creep test, confinements, permanent deformation
Procedia PDF Downloads 314236 Measurement of Asphalt Pavement Temperature to Find out the Proper Asphalt Binder Performance Grade to the Asphalt Mixtures in Southern Desert of Libya
Authors: Khlifa El Atrash, Gabriel Assaf
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Most developing countries use volumetric analysis in designing asphalt mixtures, which can also be upgraded in hot arid weather. However, in order to be effective, it should include many important aspects which are materials, environment, and method of construction. The overall intent of the work reported in this study is to test different asphalt mixtures while taking into consideration the environment, type and source of material, tools, equipment, and the construction method. In this study, several tests were conducted on many samples that were carefully prepared under the expected traffic loads and temperatures in a dry hot climate. Several asphalt concrete mixtures were designed using two different binders. These mixtures were analyzed under two types of tests - Complex Modulus and Rutting test - to evaluate the hot mix asphalt properties under the represented temperatures and traffic load in Libya. These factors play an important role to improve the pavement performances in a hot climate weather based on the properties of the asphalt mixture, climate, and traffic load. This research summarized some recommendations for making asphalt mixtures used in hot dry areas. Such asphalt mixtures should use asphalt binder which is less affected by pavement temperature change and traffic load. The properties of the mixture, such as durability, deformation, air voids and performance, largely depend on the type of materials, environment, and mixing method. These properties, in turn, affect the pavement performance. Therefore, this study is aimed to develop a method for designing an asphalt mixture that takes into account field loading, various stresses, and temperature spectrums.Keywords: volumetric analysis, pavement performances, hot climate, asphalt mixture, traffic load
Procedia PDF Downloads 302235 The Effect of Nanoclay on Long Term Performance of Asphalt Concrete Pavement
Authors: A. Khodadadi, Hasani, Salehi
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The advantages of using modified asphalt binders are widely recognized—primarily, improved rutting resistance, reduced fatigue cracking and less cold-temperature cracking. Nanoclays are known to enhance the properties of many polymers. Nanoclays are used to improve modulus and tensile strength, flame resistance and thermal and structural properties of many materials. This paper intends to investigate the application and development of nano-technological concepts for bituminous materials and asphalt pavements. The application of nano clay on the fatigue life of asphalt pavement have not been yet thoroughly understood. In this research, two type of highway asphalt materials, dense Marshall specimens, with 2% nano clay and without nano clay, were employed for the fatigue behavior of the asphalt pavement.The effect of nano additive on the performance of flexible pavements has been investigated through the indirect tensile test for the samples prepared with 2% nano clay and without nano clay in four stress levels from 200–500 kPa. The primary results indicated samples with 2% nano clay have almost double or even more fatigue life in most of stress levels.Keywords: Nano clay, Asphalt, fatigue life, pavement
Procedia PDF Downloads 445234 Microstructure of Virgin and Aged Asphalts by Small-Angle X-Ray Scattering
Authors: Dong Tang, Yongli Zhao
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The study of the microstructure of asphalt is of great importance for the analysis of its macroscopic properties. However, the peculiarities of the chemical composition of the asphalt itself and the limitations of existing direct imaging techniques have caused researchers to face many obstacles in studying the microstructure of asphalt. The advantage of small-angle X-ray scattering (SAXS) is that it allows quantitative determination of the internal structure of opaque materials and is suitable for analyzing the microstructure of materials. Therefore, the SAXS technique was used to study the evolution of microstructures on the nanoscale during asphalt aging. And the reasons for the change in scattering contrast during asphalt aging were also explained with the help of Fourier transform infrared spectroscopy (FTIR). SAXS experimental results show that the SAXS curves of asphalt are similar to the scattering curves of scattering objects with two-level structures. The Porod curve for asphalt shows that there is no obvious interface between the micelles and the surrounding mediums, and there is only a fluctuation of the hot electron density between the two. The Beaucage model fit SAXS patterns shows that the scattering coefficient P of the asphaltene clusters as well as the size of the micelles, gradually increase with the aging of the asphalt. Furthermore, aggregation exists between the micelles of asphalt and becomes more pronounced with increasing aging. During asphalt aging, the electron density difference between the micelles and the surrounding mediums gradually increases, leading to an increase in the scattering contrast of the asphalt. Under long-term aging conditions due to the gradual transition from maltenes to asphaltenes, the electron density difference between the micelles and the surrounding mediums decreases, resulting in a decrease in the scattering contrast of asphalt SAXS. Finally, this paper correlates the macroscopic properties of asphalt with microstructural parameters, and the results show that the high-temperature rutting resistance of asphalt is enhanced and the low-temperature cracking resistance decreases due to the aggregation of micelles and the generation of new micelles. These results are useful for understanding the relationship between changes in microstructure and changes in properties during asphalt aging and provide theoretical guidance for the regeneration of aged asphalt.Keywords: asphalt, Beaucage model, microstructure, SAXS
Procedia PDF Downloads 73233 Physical and Rheological Properties of Asphalt Modified with Cellulose Date Palm Fibers
Authors: Howaidi M. Al-Otaibi, Abdulrahman S. Al-Suhaibani, Hamad A. Alsoliman
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Fibers are extensively used in civil engineering applications for many years. In this study, empty fruit bunch of date palm trees were used to produce cellulose fiber that were used as additives in the asphalt binder. Two sizes (coarse and fine) of cellulose fibers were pre-blended in PG64-22 binder with various contents of 1.5%, 3%, 4.5%, 6%, and 7.5% by weight of asphalt binder. The physical and rheological properties of fiber modified asphalt binders were tested by using conventional tests such as penetration, softening point and viscosity; and SHRP test such as dynamic shear rheometer. The results indicated that the fiber modified asphalt binders were higher in softening point, viscosity, and complex shear modulus, and lower in penetration compared to pure asphalt. The fiber modified binders showed an improvement in rheological properties since it was possible to raise the control binder (pure asphalt) PG from 64 to 70 by adding 6% (by weight) of either fine or coarse fibers. Such improvement in stiffness of fiber modified binder is expected to improve pavement resistance to rutting.Keywords: cellulose date palm fiber, fiber modified asphalt, physical properties, rheological properties
Procedia PDF Downloads 320