Optimum Asphalt Research Articles

Effect of Latex Rubber as Asphalt Additive to the Characteristics of AC-WC Mixture

Quality improvement can be achieved by making innovations in the development of rubber asphalt material. This research was conducted to determine the effect of adding natural rubber as an additive to the wear-resistant Laston mixture (AC-WC). This study made 33 total samples, which were divided into 18 conventional asphalt mixtures and 15 rubber asphalt mixtures, with normal asphalt variations ranging from 5.5% - 8% and for rubber with variations of 5% - 7% of optimum asphalt weight, respectively each with an interval (0.5 %). It was mixed using a wet process. Based on the 2018 General Highways Specifications, Optimum Asphalt Content (OAC) was obtained at 7.5% and Optimum Rubber Content (ORC) at 6%. The test results for the stability and melting values of normal asphalt were 1786.22 kg and 3.56 mm, while the tests for the stability and melting values for rubber asphalt were 1181.22 kg and 3.6 mm. It can be interpreted that adding this rubber content increases the stability of the value 2x greater than the point where the stability value falls on the normal asphalt content variation of 8%.

Rutting Prediction of Asphalt Mixtures Containing Treated and Untreated Recycled Concrete Aggregate

Rutting is a crucial element of the mechanical performance characteristics of asphalt mixtures, which was the primary target of this study. The task involved substituting various portions of virgin coarse aggregate with recycled concrete aggregate materials that had been treated or left untreated at rates ranging from 25 to 100%, with a constant increase of 25%. The treatment process of recycled concrete aggregate involved soaking in acetic acid, followed by a mechanical process for a short time inside a Los Angeles machine without the balls. This research utilized two primary tests: the standard Marshall test to identify the optimal asphalt contents and the volumetric characteristics of asphalt mixtures. The other one was the wheel tracking test, which involved manufacturing 11 slabs with a dimension of 30 x 40 × 5 cm and testing them under repeated wheel loads of 700 N at 55°C to investigate rutting resistance. The results demonstrate that using RCA had a negative impact on rutting resistance, where rut depth increased by 21.64% when using 100% pre-soaked treated RCA.

Marshall Performance Analysis Of Eggshells And Cement As Filler In Asphalt Concrete Mixtures (AC - WC)

Roads are transportation infrastructure whose needs in Indonesia continue to increase, along with the increasing number of vehicles. Road construction is a construction that receives traffic loads, therefore it is expected that a road pavement layer must have a strong pavement construction and be able to receive loads from traffic users. AC-WC (Black-top Concrete - Wearing Course) asphalt layer is a road pavement construction consisting of asphalt composition, coarse aggregate, fine aggregate and filler. Fillers in asphalt mixtures function to increase the binding power of AC-WC asphalt, so as to improve mixture stability and fillers can fill the voids between aggregate particles, filler commonly used is stone ash. This research will be conducted with the addition of broiler eggshell filler and porland cement in the Asphalt Concrete wearing Course (AC-WC) mixture. The research was conducted with an experimental method conducted in the Civil Engineering laboratory of Abdurrab University. The specification used in this study is Public Road Revision 2 Year 2018, The optimum asphalt content (KAO) used was 6.5%. Based on the results of the study, the largest marshall stability and melting value is found in the 100% cement filler variation, which is 1772.7 Kg and the value of flow value (melting) 3.77 mm while the largest marshall quotient (MQ) value is found in the 25% eggshell filler variation, 75% cement, which is 529.2 Kg/mm.

Pemanfaatan Batu Sungai Mappak Kabupaten Tana Toraja Dalam Campuran Laston Lapisan Antara

This research aims to find out how the aggregate characteristics of the Mappak River in Tana Toraja Regency can be used as a pavement material for asphalt mixtures. The method used is the conventional marshall method to obtain the properties of the mixture and marshall immersion to obtain residual marshall stability from the optimum asphalt content mixture. The results of the study indicated that the aggregate characteristics of the Mappak River stone in Tana Toraja Regency with an aggregate wear value of 21.6% met the specifications as a road pavement layer material for Mixed Laston Intermediate Layers with Optimum Asphalt Content of 6.20%, with the mixed properties of Laston Intermediate Layers, namely Density, Stability, flow, VIM, VMA, VFB and Marshall Quentient have met the Specifications of Bina Marga 2018. Through Marshall Immersion testing the Laston Intermediate Layers mixture with Optimum Asphalt Content of 6.20% obtained Remaining Marshall Stability of 95.07%, which means that it meets the Specifications Bina Marga 2018, namely at least 90%..

Evaluating the Moisture Susceptibility of Asphalt Mixtures Containing Aluminum Dross as a Filler

One of the most essential components of asphalt pavements is the filler. It serves two purposes. First, this fine-grained material (diameter less than 0.075 mm) improves the cohesiveness of aggregate with bitumen. Second, produce a dense mixture by filling the voids between the particles. Aluminum dross (AD), which is a by-product of aluminum re-melting, is formed all over the world. This material causes damage to humans and the environment; stockpiling AD in landfills is not the best solution. This research studies the possibility of replacing part of the conventional filler with aluminum dross. Three percent of dross was used, 10, 20, and 30% by filler weight. The MarshallMix design method was adopted to obtain the optimum asphalt content for the selected aggregate gradation. After that, the mixture was used to evaluate the moisture damage for controlandimproved mixtures. The compressive strength and tensile strength tests were used to estimate the moisture damage to the asphalt mixtures. It was observed that replacing a part of the limestone dust filler with aluminum dross would improve moisture damage resistance. This was approved since the maximum increase in tensile strength ratio (TSR)was found to be 13.42% at 20% of AD, and the maximum increase in the index of retained strength (IRS)was found to be 8.73% at the same AD percent.

Glycerin Pitch as a partial replacement of pen 60/70 in AC-WC mixture

Glycerin pitch is a glycerol refining product from the oleochemical industry with a processing cost of US$ 400/ton. In this research, GP is used as an alternative asphalt material to replace and reduce the use of imported asphalt. GP came from 13 Indonesian oleochemical companies and was categorized based on inorganic content with sample 1 being less than 10% with an optimum GP content of 27% and sample 2 being more than 10% with an optimum GP content of 14.2%. The primary objective of this study was to explore the potential of GP as a substitute for imported asphalt. The test results showed that the optimum asphalt content for GP in sample 1 was 6% which resulted in a density of 2.26 g/cm3, VIM 4.4%, VMA 18.77%, VFB 76.53%, stability 619 kg, flow 2.83 mm, MQ 211 kg/mm. In sample 2, optimum binder content was determined at 6.1%, resulting in density of 2.34 g/cm3, VIM 5%, VMA 15.68%, VFB 68.02%, stability 1092.3 kg, flow 3.45 mm, and MQ 316 mm. The optimized Gp content value of 27% and 14.2% Gp can reduce the amount of asphalt with Marshall test results with the best stability value in sample 2.

ANALISIS PENGARUH PENGGUNAAN KULIT KERANG SEBAGAI FILLER PADA CAMPURAN AC-WC UNTUK DESAIN PERANCANGAN RUNWAY

In the AC-WC mixture, the filler is the material that significantly influences the characteristics and quality of the asphalt concrete mixture. Fillers can come from environmentally friendly materials. One material that is often found is shell waste. The method used in this research is quantitative descriptive. Based on research conducted, the shells used to meet the requirements as filler with a percentage of passing sieve no. 200 was 75.12% and the gradation composition of the mixture for AC-WC was 2% for shell filler, 50% for stone ash, 33% for screening, and 15% for the split. Meanwhile, the asphalt used in the AC-WC mixture is PG 76 Asphalt. Based on the test results, it was found that the characteristics of PG 76 asphalt were not too flexible and tended to be stiff, resistant to hot temperatures, and had homogeneous properties. In testing the AC-WC mixture, Marshall’s results obtained an optimum asphalt content of 6.3% with a stability value of 2877 kg and a flow value of 2,716 mm. This shows that the use of shell filler can increase the stability value of the mixture, however, a high stability value accompanied by low flow indicates that the mixture has a stiff pavement and will be brittle. Meanwhile, for the runway pavement thickness design at Nusawiru Airport using the FAA method and FAARFIELD software, a total thickness of 14 inches was obtained with details of a Surface Course thickness of 4 inches, a Base Course thickness of 6 inches, and a Subbase Course thickness of 4 inches.

Improvement Marshall Properties of Hot Mix Asphalt Concrete Using Polyphosphoric Acid

Modified asphalt is considered one of the alternatives to address the problems of deficiencies in traditional asphalt concrete, as modified asphalt addresses many of the issues that appear on the pavement layers in asphalt concrete, resulting from heavy traffic and vehicles loaded with loads that exceed the design loads and the large fluctuations in the daily and seasonal temperatures of asphalt concrete. The current study examined the role of polyphosphoric acid (PPA) as a modified material for virgin asphalt when it was added in different proportions (1%, 2%, 3%, 4%) of the asphalt weight. The experimental program includes the volumetric characteristics associated with the Marshall test, the physical properties, and the FTIR spectroscopy examination of virgin asphalt and polyphosphoric acid (PPA) modified asphalt. This study showed that mixtures with modified asphalt using polyphosphoric acid (PPA) by 3% achieved the typical Marshall properties at the optimal asphalt content of 4.8%, recording a 10% decrease in the optimum asphalt content for the mixtures made with virgin (unmodified) asphalt, whose proportion was 4.9% is the optimum asphalt content. PPA is available in the local markets and is considered cheaper than polymers. It is also regarded as economical as it reduces the optimum content of asphalt.

Performance Characteristics of Micro Rubber SIR 20 in Asphalt Mixtures

The development of innovative SIR 20 rubber materials in asphalt mixtures has been carried out by many previous researchers. However, there are still difficulties in the mixing process. Therefore, in this study, SIR 20 rubber was used in micro form to facilitate the mixing process. This research aims to evaluate the impact of incorporating Micro Rubber (MR) SIR 20 as a replacement for asphalt in the AC-WC mixture. The methodology involved testing the morphological characteristics of MR SIR 20 using a Scanning Electron Microscope (SEM) and EDS analysis, followed by assessing the mixture’s properties through the Marshall test. MR SIR 20 was used in proportions of 7%, 9%, and 11%. The Marshall test results indicated that adding MR SIR 20 enhances the Marshall characteristics of the AC-WC asphalt mixture compared to conventional mixtures. Additionally, increasing the MR SIR 20 content in the asphalt reduces the required optimum asphalt content relative to conventional mixtures.

Experimental Investigation of Mechanical and Electromagnetic Performance of Asphalt Concrete Containing Different Ratios of Graphite Powder as a Filler to be Potentially Used as Part of Wireless Electric Roads

This study experimentally investigates the usability of asphalt concrete pavement containing five different ratios of graphite powder (0%, 1.25%, 2.5%, 3.75% and 5% by weight of the aggregate blend or 0%, 25%, 50%, 75% and 100% of the filler content) as a filler to be potentially used as part of wireless electric roads (ER). As part of the study, first, optimum asphalt binder content for the asphalt mixes without graphite powder was determined as 5%. Then, using the determined optimum asphalt binder content, asphalt mixes containing five different ratios of graphite powder as a filler were prepared and their mechanical and volumetric properties based on Marshall mix design methodology were evaluated. As graphite powder ratios in the asphalt mixes increased, their Marshall stability, flow, voids filled with asphalt and unit weight test results mostly decreased but their air content and voids in mineral aggregate test results increased. Possible reasons for this could be: (1) lower bulk specific gravity of graphite powder, (2) higher asphalt absorbance, (3) having greater surface area compared to that of limestone filler, and (4) weak bonds between sheet-like graphite layers. Furthermore, another batch of asphalt mixes containing five different ratios of graphite powder were prepared and tested in the frequency range of 3–18 GHz for their electromagnetic permittivity properties. It was observed in this study that, except for the specimens with 100% graphite powder ratios, transmission magnitudes of all specimens were above 50% up to 8 GHz, indicating that they had comparably high transmission magnitudes so as comparably low tangent loss values. In the frequency range of 3–13 GHz, transmission magnitudes of the specimens with 25% and 50% graphite powder ratios were consistently higher than that having no graphite powder, the ones with 25% powder ratios had the highest transmission magnitudes in most of the cases in this frequency range. Considering the mechanical, volumetric and electromagnetic property test results of the asphalt mixes with five different ratios of graphite powder, it can be concluded that the use of 25% graphite powder ratio (corresponding to 1.25% of the aggregate blend used in the mixes), has a comparably lower negative effect on mechanical and volumetric properties of asphalt mixes and has a positive effect on electromagnetic permittivity properties of asphalt mixes. Asphalt mixes produced with this graphite powder ratio can be considered to be used as part of wireless ER.

Study on the Combined Effect of Municipal Solid Waste Incineration Bottom Ash and Waste Shingle in Hot Mix Asphalt.

This study investigated the positive effect of the combined use of recycled asphalt shingles (RASs) and municipal solid waste incineration (MSWI) bottom ash (B.A.) in asphalt concrete, which contributes to enhanced sustainability in pavement engineering. In addition, unlike traditional approaches that employ individual recycling material in hot mix asphalt (HMA), the combined use of the two waste materials maximizes the mechanical performance of the asphalt mixture. The addition of RAS (with 30-40% aged binder) as an additive generally enhances the strength/stiffness of the asphalt mixture. The high porosity/absorption of MSWI BA results in an additional amount of liquid asphalt binder in the mixture. As an admixture, RAS could supply the additional asphalt binder in the mixture when MSWI BA is used as an aggregate replacement. This research was conducted in two phases: (1) to examine the effect of MSWI BA alone and its optimal asphalt content (OAC), and (2) to assess the combined effect of B.A. and RAS in HMA. Multiple laboratory testing methods were employed for the mechanical performance investigation, including the Marshall stability test, rutting test, and indirect tensile test. The testing results show that the 20% B.A. replacement exhibits the best performance and that it requires an additional asphalt binder of 1.1%. For the combined use of MSWI BA and RAS, 5% RAS shows the best mechanical performance. All mixtures that contain the B.A. and RAS show greater strength than the control specimen (regular HMA).

Evaluation of Properties of Asphalt Concrete Mixture Using Basalt Aggregate from Jeju Island

In this study, the engineering properties of basalt aggregate used for asphalt road pavement on Jeju Island were evaluated, and the characteristics of the asphalt mixtures used were evaluated to assess the suitability of Jeju Island basalt as road construction material. Chemical composition and surface morphology analysis of the basalt and granite aggregate, engineering characteristics analysis, and filler property evaluation were performed. Mix design was performed, and the basic properties of three asphalt mixtures for the surface, intermediate, and base layers were evaluated. Permanent deformation resistance was evaluated through a wheel tracking test, and moisture resistance was evaluated through a dynamic immersion test and a tensile strength ratio test. The optimum asphalt contents of the asphalt mixture using low-porosity basalt aggregate and high-porosity basalt aggregate were determined to be 5.7% and 5.9% in the surface layer, 5.3% and 5.4% in the intermediate layer, and 4.7% and 5.1% in the base layer, respectively. It was found that the basic properties of the asphalt mixtures satisfied Korean quality standards. The dynamic immersion test results of low-porosity basalt aggregate and high-porosity basalt aggregate were 20% and 10%, respectively, which fall far below the quality standard of 50%. The tensile strength ratios of the basalt asphalt mixtures for the intermediate layer were 0.69 and 0.40, and they were found to increase significantly to 0.87 and 0.80 after the application of a suitable anti-stripping agent. Therefore, it was concluded that in order to apply Jeju Island basalt to asphalt pavement, an appropriate anti-stripping material must be applied.

Industrial Waste As Filler And Pamekasan Aggregate In The Mixture Asphalt Concrete - Wearing Course In Terms Of Marshall Characteristics

Utilization of hot mix asphalt in Pamekasan has increased due to the expansion of road networks for construction and maintenance purposes. The commonly used hot asphalt is AC-WC (Asphalt Concrete - Wearing Course), which serves as the hot asphalt layer for the pavement construction. Historically, the production of hot asphalt mix in Pamekasan involved obtaining materials from outside the Madura region, leading to high production costs. In response to this issue, there is a need for innovation in the composition of hot asphalt mix materials to enhance cost efficiency, especially considering the abundant quantity of materials available in Pamekasan. An innovative approach includes using crushed stone from Pamekasan as an aggregate in hot asphalt mix and incorporating waste materials such as Batumarmar limestone powder and fly ash as fillers. The utilization of local materials from Pamekasan and waste is expected to reduce production costs. For this purpose, 45 samples were created with different percentages, and the Marshall test method was employed to determine values such as density, flow, VMA (voids in mineral aggregate), VIM (voids in mineral aggregate filled with asphalt), VFA (voids filled with asphalt), and stability. Based on the test results, the Optimum Asphalt Content (OAC) was found in a mixture with 4% filler variation and 6% asphalt, yielding a density of 2.287, stability of 917 kg, flow of 3.467 mm, Marshall Quotient of 250.09 kg/mm, VIM of 3.67%, VMA of 15.18%, and VFB (voids filled with bitumen) of 77.68%. Another optimum mixture was identified with a 6.1% asphalt and 10% filler variation, resulting in a density of 2.280, stability of 1,127 kg, flow of 4.50 mm, Marshall Quotient of 250.45 kg/mm, VIM of 3.66%, VMA of 15.16%, and VFB of 76.70%. Additionally, a 6.2% asphalt and 10% filler variation produced a density of 2.285, stability of 1,061 kg, flow of 4.00 mm, Marshall Quotient of 365.28 kg/mm, VIM of 3.31%, VMA of 15.64%, and VFB of 78.84%.

Marshall Asphalt Mix and Superior Performance Asphalt Mix in Oman: A Comparative Study

The mix design procedure used in Superior Performance Asphalt Pavements (Super-pave) was created by the Strategic Highway Research Program (SHRP) in response to the limitations and empirical approach of Marshall methodology. This study aims to compare the Marshall asphalt mixture design method with the Super-pave asphalt mixture design procedures. Locally available aggregates commonly used in asphalt concrete mixtures in Oman were used. The asphalt mixtures were made with aggregate and asphalt-binder with a penetration grade of 60/70 and PG 64-10. Samples from two mixes were made accordingly. Volumetric properties analysis, flow, Marshall stability, and loss of Marshall stability tests were carried out. According to the study findings, the optimum asphalt composition was 4.5% when utilizing the Marshall methodology and 5.5% when using the Super-pave approach. Furthermore, the Super-pave specimens showed less loss of Marshall stability (22.22%) than the Marshall specimen (30.09%).

Evaluation of eco-friendly asphalt mixtures incorporating waste plastic aggregates and additives: Magnesium, fly ash, and steel slag

This research explores the applicability of waste plastic aggregate (WPA) in the development of environmentally friendly asphalt mixtures, contributing to resource conservation, waste recycling, and the prevention of environmental issues associated with landfilling and incineration. Through experimental analysis of durability and common characteristics, the research investigates the optimal asphalt content (OAC) for practical implementation, particularly in substituting natural aggregates with waste plastic aggregates in asphalt mixture production. It examines the feasibility of producing asphalt mixtures by incorporating WPA and focuses on preventing microplastic generation using WPA in lower pavement layers. Additive materials, including Magnesium, fly ash, and steel slag powder, were used to enhance the properties of the mixtures. The experimental variation ratios in this research were assessed through a meticulous mixture design process involving the incorporation of WPA at varying contents (0%, 3%, 5%, 7%, and 10%) in both base (BB-2) and middle (MC-1) asphalt layers, enabling a comprehensive evaluation of the performance and characteristics of the resulting asphalt mixtures in comparison to control mixtures. Various tests, including wheel tracking, deformation strength, dynamic stability, crack resistance, and water resistance, are conducted to evaluate the performance of the mixtures. The findings indicate that 5% WPA can be seamlessly integrated into the asphalt mixture without external issues, and it exhibits satisfactory performance during the manufacturing process. The utilization of waste plastic fine aggregate results in non-uniform voids, while mixtures with 7% WPA fail to meet water resistance requirements. Coarse aggregates show better resistance to plastic deformation than fine aggregates, and mixtures with 5% WPA incorporating waste plastic fine aggregate demonstrate the highest resistance. Overall, this research provides valuable insights into the utilization of waste plastic aggregate in asphalt mixtures, highlighting its potential to enhance sustainability and pave the way for resource-saving practices in road construction, with the use of additive materials further improving the mixture properties.

Experimental Investigation of Mechanical and Electromagnetic Performance of Asphalt Concrete Containing Different Ratios of Graphite Powder as a Filler to be Potentially Used as Part of Wireless Electric Roads

This study experimentally investigates the usability of asphalt concrete pavement containing five different ratios of graphite powder (0%, 1.25%, 2.5%, 3.75% and 5% by weight of the aggregate blend or 0%, 25%, 50%, 75% and 100% of the filler content) as a filler to be potentially used as part of wireless electric roads (ER). As part of the study, first, optimum asphalt binder content for the asphalt mixes without graphite powder was determined as 5%. Then, using the determined optimum asphalt binder content, asphalt mixes containing five different ratios of graphite powder as a filler were prepared and their mechanical and volumetric properties based on Marshall mix design methodology were evaluated. As graphite powder ratios in the asphalt mixes increased, their Marshall stability, flow, voids filled with asphalt and unit weight test results mostly decreased but their air content and voids in mineral aggregate test results increased. Possible reasons for this could be: (1) lower bulk specific gravity of graphite powder, (2) higher asphalt absorbance, (3) having greater surface area compared to that of limestone filler, and (4) weak bonds between sheet-like graphite layers. Furthermore, another batch of asphalt mixes containing five different ratios of graphite powder were prepared and tested in the frequency range of 3–18 GHz for their electromagnetic permittivity properties. It was observed in this study that, except for the specimens with 100% graphite powder ratios, transmission magnitudes of all specimens were above 50% up to 8 GHz, indicating that they had comparably high transmission magnitudes so as comparably low tangent loss values. In the frequency range of 3–13 GHz, transmission magnitudes of the specimens with 25% and 50% graphite powder ratios were consistently higher than that having no graphite powder, the ones with 25% powder ratios had the highest transmission magnitudes in most of the cases in this frequency range. Considering the mechanical, volumetric and electromagnetic property test results of the asphalt mixes with five different ratios of graphite powder, it can be concluded that the use of 25% graphite powder ratio (corresponding to 1.25% of the aggregate blend used in the mixes), has a comparably lower negative effect on mechanical and volumetric properties of asphalt mixes and has a positive effect on electromagnetic permittivity properties of asphalt mixes. Asphalt mixes produced with this graphite powder ratio can be considered to be used as part of wireless ER.

ANALYSIS OF MARSHALL CHARACTERISTICS WITH FLY ASH MATERIAL FOR STONE DUST SUBSTITUTION AS FILLER IN HRS-WC MIXTURE

Lataston asphalt mix is a thin layer of asphalt concrete that is often used on light-traffic roads because it produces roads with good flexibility and durability. An economical way of doing this is to vary the asphalt mix, especially by modifying fillers, to improve the quality of the road pavement and asphalt mix. So, an alternative was found, namely the use of fly ash, residue from the Asam-Asam PLTU. The filler material for fly ash which will be varied with the filler for stone dust, plays a role in filling the voids between aggregate grains in the Hot Rolled Sheet-Wearing Course (HRS-WC) mixture with each predetermined composition. This study aims to determine the characteristics of the HRS-WC asphalt mixture with respect to the utilization rate of rock dust and fly ash fillers. To find out the characteristics of a HRS-WC mixture with mixed variations of the two fillers, the method that will be used is the Marshall Test by analyzing each characteristic of the parameters to be obtained in accordance with the 2018 Revised Highways Specifications II Year 2018 to make the mixture hot asphalt. The bitumen content used in this study was 4.5%, 5.0%, 5.5%, 6.0%, and 6.5%, with varying levels of fly ash and rock dust filler, namely 100%: 0%, 80%: 20%, 50%: 50%, 20%: 80%, and 0%: 100%. The results of the Marshall characteristic calculation analysis show that the asphalt mixture with lataston is very influential in the substitution of rock ash as a fly ash filler. Lataston asphalt mixture tends to be stiff and easily cracked because it has a high stability value of 1,615.38 kg and the lowest flow value of 4.10% in the 100% fly ash filler variation. At optimal asphalt content, the HRS-WC asphalt mixture for each variation in the range of fly ash and rock dust produces a decreased asphalt content because the water absorption capacity of rock dust is less than that of fly ash filler, so less asphalt is needed. In addition, the HRS-WC asphalt mixture also shows increasing durability, along with the replacement of rock dust filler with fly ash filler, which can be seen from the increased stability values, MQ values, and VFB values.

Drainage Performance of Long Longitudinal Slope and High Safety Permeable Asphalt Pavement

Permeable asphalt pavement refers to an asphalt mixture layer with an air void content of more than 18% and internal water permeability and drainage capabilities that can quickly drain away water on the road surface, improve rainy day travel safety, and improve ride comfort. This paper aims to explore the optimal asphalt mixture design for long longitudinal slope pavement (referred to as the FAM mixture). By using CT scanning technology to analyze the air void content of different rotated and compacted asphalt mixture specimens and extensively testing and evaluating the performance of permeable pavement mixtures, the following conclusions are drawn: Based on the research philosophy of functional integration, a new asphalt mixture gradation suitable for long longitudinal slope roads is proposed, with the optimal key factor composition being: 0.075 mm passing rate of 7%, 2.36 mm passing rate of 20%, 9.5 mm passing rate of 55%, and an oil-stone ratio of 4.8%. The FAM mixture was divided into three parts for air void analysis, with the upper part having a slightly higher air void content than the lower part. The air void distribution diagram of the FAM mixture is concave, with higher air void rate curves on both sides and a lower middle curve. Through dynamic modulus testing, the strength requirement for the road asphalt mixture in the pavement structure design was evaluated. It was found that at high temperature conditions (50 °C), the minimum dynamic modulus value of the FAM mixture was 323 MPa, with a peak value of 22,746 MPa at a temperature of −10 °C and a frequency of 25 HZ. The dynamic modulus value at high temperature conditions is lower than at low temperature conditions, while the dynamic modulus value at high frequency conditions is higher than at low frequency conditions. This study provides useful information and experimental data for the design of new asphalt mixtures for long longitudinal slope roads and has conducted in-depth research on the air void distribution and performance of the mixture, providing strong support for related research fields and practical applications.

EXPERIMENTS USING ABS PLASTIC SEEDS (ACRYLONITRILE BUTADIENE STYRENE) AS ADDITIONAL MATERIALS IN PORUS ASPHALT MIXTURE

Increasing the strength of the porous asphalt mixture in the field of road contraction, in this context, porous asphalt is often used as road pavement. ABS plastic pellets (Acrylonitrile Butadiene Styrene) have the same properties as asphalt, namely, thermoplastic has a penetration value equivalent to asphalt pen 60/70, plays an important role in road pavement adhesives as an alternative and has high strength and is resistant to deformation itself. The objective of the experiment was to determine the characteristics of Marshall on optimum asphalt content (KAO) and the effect of adding ABS plastic pellets on the performance of porous asphalt was reviewed based on the Marshall test, Cantabro Loss and Asphalt Flow Down. The research used experimental testing methods in the laboratory. The research was conducted with asphalt pen content of 60/70, namely 4%, 4.5%, 5%, 5.5% 6% and additional levels of ABS plastic pellets 0%, 2%, 4%, 6% and 8%. From the planned grade for the addition of ABS plastic pellets mentioned above, the optimum bitumen content is obtained, namely 6% with a VIM value at 6% content of 23.61%, for a VMA value of 27.20%, for a stability value of 924.95 kg and the flow value obtained was 3.23 mm while the MQ value was 311.15 kg/mm. with standard or parameters namely AAPA 2004(Australian Asphalt Pavement Association).

Micro-structural characteristics of asphalt mixture and its effect to mechanical performance based on two-stage mixing method

Conventional asphalt mixtures are prone to material separation during mixing, causing rutting, loosening, and cracking of the pavement. This study proposes a two-stage mixing method to address these problems. The theoretical asphalt film thickness is calculated, and a physical index of the mixture for aggregates with different specific surface areas is used to determine the optimal asphalt mixing ratio. The microstructural characteristics and mechanical properties of the mixtures are evaluated using digital image processing, laboratory experiments, and correlation analyses. The results show that the two-stage mixing process mixes the aggregate more thoroughly, resulting in a uniform asphalt film with sufficient contact between the asphalt particles, improving the mixture’s mechanical performance. The results of this study can be used to improve the design of asphalt mixtures and reduce the use of petroleum asphalt.