Optimum Asphalt Research Articles

Asphalt Concrete Mixtures with Coal Bottom Ash as Fine Aggregate Substitution and Crumb Rubber as Asphalt Substitution

Abstract This research conducting the substitution of coal bottom ash and crumb rubber in asphalt concrete wearing course (AC-WC) mixtures. The objective is to help reduce waste materials and obtaining Marshall parameters that meet the requirements for asphalt mixtures. The percentage variations used for the substitution were 6%, 9%, and 12% coal bottom ash and 5%, 8%, and 11% crumb rubber. In Marshall test used varies asphalt content, the optimum asphalt contents (OAC) obtained were 5.85%, 6.03%, and 6.2%. Then, the OAC was used in asphalt concrete mixtures with coal bottom ash as fine aggregate substitution. The best results were obtained at the combination of 6% coal bottom ash and 5.85% asphalt content. Consequently, the combination was used in the mixtures by adding crumb rubber as the substitution of the asphalt. The results shows that the Marshall parameters obtained by all percentages of crumb rubber substitution have fulfilled the requirements with the highest stability of 1928.16 kg. The durability test on asphalt concrete mixtures with 6% coal bottom ash as fine aggregate substitution and 11% crumb rubber as asphalt substitution with 5.85% asphalt content obtained 92.82%, so that the requirement of ≥90% of the Bina Marga 2018 Specifications Revision 2 (2020) have been fulfilled.

Performance of Road Pavement Using AC-WC Mixture with Glycerin Oleochemical Waste Substitution Material Based on Marshall Testing and IRI Value.

Abstract By the end of 2021, PT Pertamina was the sole oil asphalt producer in Indonesia, with a production capacity of 350,000 tons per year. However, domestic asphalt demand exceeds this supply, leading to 75% of asphalt still being imported. To reduce imports, Glycerin Pitch (GP), a waste product from the oleochemical industry and classified as a Toxic and Hazardous Substance (B3), can be used as a substitute for asphalt. Indonesia produces 650,000 tons of glycerol annually, with 3% resulting in GP. Tests on GP with inorganic content <10% and >10% were conducted. Rheology tests showed penetration values of 62.83 and 60.4 (0.1 mm), softening points of 60.5°C and 56.5°C, kinematic viscosities of 1197 cSt and 903 cSt, ductility >100 cm for both, and specific gravities of 1.074 g/cc and 1.054 g/cc. Aggregate tests revealed an abrasion value of 16.71%, flat and elongated particles at 7.52% (split) and 8.49% (screen), and material passing sieve No. 200 at 0.87% (coarse) and 9.49% (fine). The asphalt mixture design showed an aggregate gradation of 12% split, 44% screen, 41% stone dust, and 3% filler. The optimum GP content was 27% for GP1 and 14.2% for GP2, with an optimum asphalt content of 6%. Mixing and compaction temperatures were 130°C and 150°C for ACWC+GP1 and 150°C for ACWC+GP2. The Marshall Quotient was 211 Kg/mm for ACWC+GP1 and 316 Kg/mm for ACWC+GP2. Field tests on two segments (Pen 60/70 + GP1 and GP2) showed an International Roughness Index (IRI) of 3.21 and 2.89, respectively, classified as good. These findings suggest that GP is a viable substitute in asphalt mixtures, reducing import dependence while efficiently utilizing oleochemical waste.

Study on the Effect of SBS/HVA/CRM Composite-Modified Asphalt on the Performance of Recycled Asphalt Mixtures.

To investigate the feasibility of composite modification techniques in improving the performance of recycled asphalt mixtures, in this study, the high-viscosity agent (HVA) and crumb-rubber materials (CRM) were used to modify asphalt with a styrene-butadiene-styrene block copolymer (SBS), in order to prepare SBS-HVA and SBS-CRM composite-modified asphalts. The virgin asphalt mixtures, as well as three asphalt types of recycled asphalt mixtures with 50% reclaimed asphalt pavement (RAP) content, were designed. The optimal asphalt content of the four types of asphalt mixtures was analyzed, and the rutting test, the asphalt bond strength test, the moisture-induced sensitivity test, and the low-temperature cracking resistance test were conducted to investigate the performance of the four types of asphalt mixtures. The results showed that the higher the asphalt kinematic viscosity, the higher the optimum asphalt content of the asphalt mixtures under the same air voids. HVA significantly improves the adhesion between SBS-modified asphalt and aggregate under dry conditions, while SBS-CRM composite-modified asphalt performs similarly to SBS-modified asphalt. Before and after water immersion, the degree of pull-out strength decay between the asphalts and aggregates follows the sequence of SBS-CRM- > SBS- > SBS-HVA-modified asphalts. Additionally, the residual pull-out work follows the sequence of SBS-HVA- > SBS-CRM- > SBS-modified asphalt. SBS-CRM composite-modified asphalt can significantly improve the moisture sensitivity of recycled asphalt mixtures, as well as low-temperature cracking resistance, while SBS-CRM composite-modified asphalt only improves the low-temperature cracking resistance of recycled asphalt mixtures, and does not improve the moisture sensitivity. Based on the results, it is recommended to select the appropriate composite modification method based on the climate and loading conditions, to maximize the value of asphalt, and to achieve sustainable and durable pavement.

Analysis of Surface Texture of Asphalt Mixture with Sand Circle Method

A road is usually defined as an infrastructure connecting a zone to other zones. As service and safety are essential for vehicle users, any conditions related to the pavement, including surface texture, are considered. The importance of this matter is that many researchers or practitioners are concerned with the quality of asphalt mixtures, whether structural or functional, which affect the safety and security of road users, mainly related to the texture of the pavement surface. This research aims to determine the texture depth (MTD, Mean Texture Depth). The research method used is the circle sand method, which is tested using the Sand Patch tool. The asphalt mixture type uses AC-WC with a composition of 39% coarse aggregate, 54.5% fine aggregate, and 6.5% filler. Optimum Asphalt Content of 6.28% and Density of 2.28 were obtained, and texture depth of 0.549 mm was more significant than 0.45 mm (Bina Marga 2010 revision 3). The conclusion is based on the design composition of the aggregate mix in the AC-WC asphalt mixture, which has a safe texture.

Experimental Investigation of Indirect Tensile Strength of Hot Mix Asphalt with Varying Hydrated Lime Content at Low Temperatures and Prediction with Soft-Computing Models

If asphalt pavements are exposed to cold weather conditions and high humidity for long periods of time, cracking of the pavement is an inevitable consequence. In such cases, it would be a good decision to focus on the filler material, which plays an important role in the performance variation in the hot asphalt mixtures used in the pavement. Although the use of hydrated lime as a filler material in hot asphalt mixtures is a common method frequently recommended to eliminate the adverse effects of low temperature and to keep moisture sensitivity under control in asphalt pavements, the sensitivity of the quantities of the material cannot be ignored. Therefore, in this study, an amount of filler in the mixture was replaced with hydrated lime (HL) filler additive at different rates of 0%, 1%, 2%, 3% and 4%. These asphalt briquettes, designed according to the Marshall method, have optimum asphalt contents for samples with specified HL content. In this study, where the temperature effect was examined at five different levels of −10 °C, −5 °C, 0 °C, 5 °C and 25 °C, the samples were produced in two different groups, conditioned and unconditioned, in order to examine the effect of water. The indirect tensile strength (ITS) test was applied on the produced samples. Experimental study showed that HL additive strengthened the material at low temperatures and made it more resistant to cold weather conditions and humidity. In the second part of the study, two different prediction models with varying configurations were introduced using nonlinear regression and feed-forward neural networks (FFNNs) and the best prediction performance among these was investigated. Examination of the performance measures of the prediction models indicated that ITS can be accurately predicted using both methods. As a result of comparing the developed models with the experimental data, the model provides significant contributions to the evaluation of the relationship between the ITS values obtained with the specified conditioning, temperature changes and HL contents.

Effect of Using Fine Volcanic Ash Instead of Crushed Basalt Filler in Hot Mix Asphalt

Numerous studies over the years have demonstrated the significance and impact of filler in influencing the physical and mechanical properties of Hot Mix Asphalts (HMAs). To overcome such issues, as environmentally friendly alternatives, several different materials for construction have been proposed. This led to an investigation into the potential use of fine volcanic ash (FVA) as a hot mix asphalt filler alternative. In order to prepare bituminous concrete mix sample with conventional basalt filler (BF) as control mix. The Marshall Mix design approach was used to calculate the effective bitumen content. A total of 15 bituminous concrete mix specimens with bitumen content of 4%, 4.5%, 5%, 5.5%, and 6% were created, and the optimum asphalt content was 5.24 %. The impacts of five different (FVA) samples with filler contents of 15%, 30%, 45%, and 60% by weight were compared with respect to bituminous concrete performance. The Marshall stability of a total of 30 samples with varying amounts of (FVA) were investigated. The outcomes were compared with a conventional bituminous concrete mixture. The results showed that fine volcanic ash may substitute 30% of the basalt filler at a bitumen content of 5.24%, 13.84 KN Marshall stability value, 4.0% air voids, 74.77% VFB, 2.380 g/cm3 bulk density and 3.54 mm flow. Therefore, the combination of 30% Fine Volcanic Ash by weight of Basalt Filler satisfies the ASTM Specifications, while the remaining VA content satisfies the basic requirements of the ASTM Specifications.

Mechanical Performance of a Hot Mix Asphalt Modified with Biochar Obtained from Oil Palm Mesocarp Fiber

A recently used material that shows environmental and technical advantages for use as an asphalt binder modifier is biochar (BC). Different biomasses can be converted into BC by pyrolysis. One agro-industrial biomass that is abundant in copious quantities is oil palm mesocarp fiber (OPMF) obtained from African palm cultivation. In the present study, the use of a BC obtained from OPMF (BC-OPMF) as a modifier of asphalt binder (AC type) to produce a hot mix asphalt (HMA) was evaluated. This type of BC has not been investigated or reported in the reference literature as a binder and/or asphalt mix modifier. Initially, AC was modified with BC in three ratios (BC/AC = 5, 10, and 15%, with respect to mass) to perform penetration, softening point, and rotational viscosity tests; rheological characterization at high and intermediate temperatures; and scanning electron microscope (SEM) visualization. Based on this experimental phase, BC/AC = 10% was chosen to manufacture the modified HMA. Resistance parameters under monotonic loading (stability—S, flow—F, S/F ratio of the Marshall test, and indirect tensile strength in dry—ITSD and wet—ITSC conditions) and cyclic loading (resilient modulus, permanent deformation, and fatigue resistance under stress-controlled conditions) were evaluated on the control HMA (AC unmodified) and the modified HMA. Additionally, the tensile strength ratio (TSR) was calculated to evaluate the resistance to moisture damage. Abrasion and raveling resistance were evaluated by performing Cantabro tests. BC-OPMF is shown to be a sustainable and promising material for modifying asphalt binders for those seeking to increase stiffness and rutting resistance in high-temperature climates, resistance to moisture damage, raveling, and fatigue without increasing the optimum asphalt binder content (OAC), changing the volumetric composition of the HMA or increasing the manufacturing and construction temperatures.

CHARACTERISTICS OF YALIMO PAPUA KINANG JINGKION POWDER AS FILLER IN HRS-WC MIXTURE

<span lang="EN-US">Kinang Jingkion is the name of a region in Yalimo Regency, Papua, which has unique material deposits with specifications that make it suitable for use as aggregate in road pavement, including as filler in powder form. Jan Ukago, one of the first researchers on this aggregate, named the material after the region or location, so the material from the Kinang Jingkion region is now called Kinang Jingkion material. The high construction costs in the Yalimo region and generally in the Papua Mountains are caused by logistics, where materials such as cement and asphalt are mobilized using airplanes. With the alternative of using local filler material, it will eliminate long and expensive mobilization. The testing method was carried out according to the 2018 General Specifications Revision 2, Directorate General of Highways and Indonesian National Standard (SNI) for each test, including asphalt, coarse and fine aggregates, and Kinang Jingkion material. The Optimum Asphalt Content (OAC) obtained from Kinang Jingkion Filler was 6.85%. The Marshall characteristic test results for Kinang Jingkion Filler at OAC of 6.85% showed a stability value of 1194.40 Kg, MQ of 460.2 Kg/mm, VIM of 2.68%, and VFB of 80.16</span>

Fiber Showdown: A Comparative Analysis of Glass vs. Polypropylene Fibers in Hot-Mix Asphalt Fracture Resistance

Cracks in asphalt mixtures compromise the structural integrity of roads, increase maintenance costs, and shorten pavement lifespan. These cracks allow for water infiltration, accelerating pavement deterioration and jeopardizing vehicle safety. This research aims to evaluate the impact of synthetic fibers, specifically glass fiber (GF) and polypropylene fiber (PPF), on the crack resistance of Hot-Mix Asphalt (HMA). An optimal asphalt binder content of 5% was used in all sample designs. Using the dry mixing technique, GFs and PPFs were incorporated into the HMA at dosages of 0.50%, 1.00%, and 1.50% by weight of the aggregate. The effects of these fibers on the mechanical fracture properties of the HMA were assessed using Semi-Circular Bending (SCB), Indirect Tensile Asphalt Cracking Tests (IDEAL-CTs), and Three-Point Bending (3-PB) tests. This study focused on fracture parameters such as fracture work, peak load, fracture energy, and crack indices, including the Flexibility Index (FI) and Crack Resistance Index (CRI). The results from the SCB and IDEAL-CT tests showed that increasing GF content from 0.5% to 1.5% significantly enhances the flexibility and crack resistance of HMA, with FI, CRI, and CT Index values increasing by 247.5%, 55%, and 101.35%, respectively. Conversely, increasing PPF content increases the mixture’s stiffness and reduces its crack resistance. The PP-1 mixture exhibited higher FI and CT Index values, with increases of 31.1% and 10%, respectively, compared to the PP-0.5 mixture, based on SCB and IDEAL-CT test results. The SCB, IDEAL-CT, and 3-PB test results concluded that fibers significantly influence the fracture properties of bituminous mixtures, with a 1% reinforcement dosage of both PPFs and GFs being optimal for enhancing performance across various applications.

Identifying the effect of adding coconut coir on the characteristics of the top layer of pure natural buton asphalt concrete wearing course (AC-WC)

Buton Asphalt is natural asphalt originating from Buton Island (Indonesia), with the potential deposit amount reaching up to 662 million tons. This substantial domestic mining potential must be utilized for domestic road needs and to boost the country's economy. However, Buton asphalt's utilization is minimal compared with imported oil asphalt, which reached a usage rate of up to 94 % in 2022. Therefore, as a form of a solution-oriented policy, Buton asphalt is included as one of the 21 commodities in the Strategic Roadmap for Downstream Investment in Indonesia, followed by various supportive regulations for developing this Buton asphalt product. One of the leading products the government targets is natural pure Buton asphalt. This product consists of >99 % bitumen content after extraction, also called Pure Buton Asphalt. The idea was to modify pure Buton asphalt with coconut coir to increase the Marshall Stability and Dynamic Stability values to make the asphalt mixture more resistant to vehicle loads and rutting. The tests were conducted to determine the optimum asphalt content (OAC) of the mixtures, Marshall's Stability comparison, and the dynamic stability test using a Wheel Tracking Machine to identify the comparison of permanent deformation. This study analyzed the Marshall characteristics and dynamic stability characteristics with variations in coconut coir content of 0.5 %, 0.75 %, and 1 % by weight of asphalt and variations in coconut coir length of 0.5 cm, 1 cm, and 1.5 cm. Based on the results of this study, the optimum asphalt content in this study is 6.76 %, where pure Buton Asphalt modified with coconut coir has an increase in Marshall's stability value and dynamic stability value compared to pure Buton asphalt without additional coconut coir

Modeling and design optimization of the performance of stone matrix asphalt mixtures containing low-density polyethylene and waste engine oil using the response surface methodology

In recent years, the use of waste plastic materials such as low-density polyethylene (LDPE) to modify asphalt binders and enhance mixture performance has garnered significant attention. One major concern with using such materials is the higher production temperature required, which necessitates the use of a bitumen extender agent, such as waste engine oil (WEO), to reduce the viscosity and mixing temperature. Therefore, using these stabilizing additives can reduce the consumption of virgin binder, especially for Stone Matrix Asphalt (SMA) mixtures, which require higher asphalt content. This study aimed to optimize the design of SMA modified by LDPE and WEO to minimize the optimum asphalt content (OAC) and mixing temperature while maximizing SMA performance. To achieve this, Response Surface Methodology (RSM) was utilized to develop the necessary models for optimizing design and predicting performance. The selected independent variables (factors) for the design include LDPE content, WEO content, OAC, and mixing temperature. Meanwhile, the responses (dependent variables) consist of Marshall stability, rut depth, tensile strength ratio, and resilient modulus, which were used to determine the best mix design. The findings demonstrated that the suggested models for the output variables can predict performance with a higher level of confidence. The Analysis of variance (ANOVA) demonstrated that predictive models were significant and well-fitted, with a coefficient of determination (R2) of higher than 0.80, an adequate precision value of greater than 4, and a low p-value (less than 0.05). The error percentage between the RSM-predicted and actual values was less than 5 %, indicating that RSM-established models can accurately and efficiently predict the SMA performance. The best mix design of the SMA mixture modified by LDPE and WEO was found to be 10 % LDPE, 3.91 % WEO, 5.92 % OAC, and mixing temperature of 152.24°C with a combined desirability of 82.8 %.

Pemanfaatan Penambahan Limbah Inner-Tube Rubber dan Penggunaan Abu Cangkang Kemiri Sebagai Substitusi Filler pada Campuran AC-WC

Various problems that occur in asphalt damage in Indonesia have triggered new innovations to deal with existing problems, one of which is by improving the quality of asphalt by adding substances (additives) or substitutions to the aggregate composition. This study aims to determine the utilization of inner tube rubber waste and the use of candlenut shell ash as a substitute filler in the AC-WC mixture. This study is an experimental study. The manufacture of test objects using an AC-WC mixture with a total of 18 test objects was then tested using the Marshall method. The results of this study indicate that the use of inner-tube rubber waste and candlenut shell ash greatly affects the Marshall parameter value. With an Optimum Asphalt Content of 6%, the best variation content was obtained at 3% of inner tire rubber additives and 25% substitution of candlenut shell ash as filler with a density value of 2.341 gr/cm3, VMA 15.50%, VIM 4.36%, VFA 71.87%, stability 1730.79 kg, flow 3.36 mm and MQ 565.01 kg/mm ​​which meets the 2018 Bina Marga Specifications Revision 2.

Pengaruh Penambahan Cacahan Limbah Plastik HDPE (High Density Polyethylene) Sebagai Bahan Tambah Campuran Laston AC-WC (Asphalt Concrete-Wearing Course) Terhadap Karakteristik Marshall

In increase quality vulnerable roads in Indonesia damaged Because influenced by weather, water, load vehicle excess, and construction insufficient pavement​ fulfil requirements, required material add as much as you can increase strength and help repair construction road asphalt the Utilization material waste plastic in construction pavement become good alternative​ in in increase quality pavement road. Objective study This is For know How influence addition waste plastic type High Density Polyethylene (HDPE) against Marshall Laston AC-WC characteristics with variation rate HDPE plastic at 0%, 2%, 4%, and 6%. Marshall characteristics reviewed is mark density (density), VIM (void in mix), VMA (void mineral aggregate), VFA (void filled with asp halt), melting (flow), and stability. Method research used​ with method experiments in the laboratory and refers to Specification General Highways​ 2018. Research results shows the Marshall test on the mixture Laston AC-WC with addition rate HDPE plastic 0%, 2%, 4%, and 6% can be raise mark density (density), stability , VFA ( Void Filled with Asphalt), whereas For VIM (void in mix), VMA (Void Mineral Aggregate) and melt (flow) values experienced decline . Marshall parameter values obtained​​ fulfil standard Specification General Highways​ 2018. Percentage​ rate optimum asphalt (KAO) obtained is 6.0%, Marshall test of variation material plus waste plastic best value​ For density, melting (flow), stability, VIM , VMA, and VFA, namely at levels waste plastic 2%.

Analisis Pengaruh Serbuk Besi Sebagai Substitusi Agregat Halus pada Lataston Lapis Aus (HRS-WC) Terhadap Kinerja Jalan Beraspal

Damage to flexible pavements is still commonly found in Indonesia. As technology develops, there is some research regarding using iron powder as an alternative replacement material for asphalt mixtures. This research used iron powder waste as a substitute for fine aggregate in Hot Rolled Sheet–Wearing Course with levels of 0%,15%,30%, and 45%. The purpose of this research to determine the Optimum Asphalt Content (OAC) and optimum percentage of iron powder waste addition as a substitute for fine aggregate to the indicator of Marshall test based on The General Specification of Bina Marga 2018 (Revision 2). Based on Marshall testing that has been carried out, the OAC values are 7,5% with an average of stability 2040,46 kg, flow 3,40 mm, MQ 600,24 kg/mm, voids in mix 4,69%, voids in mineral aggregate 18,30%, and voids filled with asphalt 74,39%. While the optimum percentage of iron powder value is 13% with an average of stability 2091,90 kg, flow 3,17 mm, MQ 662,79 kg/mm, voids in mix 3,92%, voids in mineral aggregate 17,59%, and voids filled with asphalt 77,72%. The result met the General Specification of Bina Marga 2018 (Revision 2). The addition of iron powder as a substitute for fine aggregate in HRS-WC is can increase stability but reduce air voids in the asphalt mixture. This result makes the asphalt mixture more impermeable and plastic.

PERBANDINGAN NILAI KARAKTERISTIK MARSHALL UNTUK CAMPURAN AC-WC MENGGUNAKAN QUARRY AKANUNU DAN QUARRY HERA

Asphalt Concrete - Wearing Course (AC-WC) is a road construction layer consisting of coarse aggregate, fine aggregate, filler, and hard asphalt. This material is mixed, laid, and compacted at specific temperatures to form a durable and strong road surface layer. Enhancing road resilience against various factors causing damage is essential to maintain transportation systems and ensure even economic growth across regions. In this context, it's important to compare the physical and mechanical characteristics of AC-WC mixtures using materials from Quarry Akanunu and Quarry Hera. The aim of this study is to assess the performance of AC-WC mixtures from both quarries using the standard Marshall 2 x 75 blows testing method. The research findings indicate that using an optimal asphalt content of 5.85% from Quarry Akanunu, there are differences in Marshall characteristics compared to mixtures using materials from Quarry Hera. At an asphalt content of 5.85% from Quarry Akanunu, the differences in stability values reached 67.28 kg, flow 0.13 mm, VIM (Void in the Mix) 0.31%, VMA (Void in Mineral Aggregate) 0.14%, VFB (Void Filled with Bitumen) 1.22%, and Marshall Quotient (MQ) 31.43 Kg/mm. Meanwhile, using an optimal asphalt content of 5.90% from Quarry Hera, the differences in stability values reached 69.90 kg, flow 0.15 mm, VIM 0.31%, VMA 0.14%, VFA 1.22%, and MQ 33.12 Kg/mm. From this analysis, Quarry Hera shows slightly better performance in terms of stability and other Marshall characteristics compared to Quarry Akanunu, although both mixtures meet the specifications of Bina Marga 2018 revision 2.

Phase-Change/Salt-Based Slow-Release Composite Material for Anti-Icing and Snow-Melting

Currently, self-desiccating asphalt mixtures on roads mainly incorporate phase-change materials or salt-based slow-release agents individually for de-icing. However, pure phase-change material mixtures have limited anti-freezing efficiency and short heat-release duration, making them impractical for large-scale snow melting; meanwhile, salt-based slow-release agents suffer from rapid deterioration in de-icing performance. To address these issues encountered, herein, we introduce the phase-change/salt-based slow-release composite materials via the integration of these two materials and investigate their pavement and de-icing performance with the asphalt mixture. For the pavement performance, the optimal asphalt–aggregate ratio for the anti-icing asphalt mixture was found to be 5.1% For anti-bonding and de-icing performance, the electrical conductivity tests, bonding pull-off tests, and interfacial contact melting experiments were conducted. The results indicate that the latent heat of the TH-ME5 (phase-change material) can delay the decrease in environmental temperature and inhibit salt release from T-SEN (salt-based slow-release material), thereby extending the lifespan of the anti-icing asphalt mixture. These results demonstrate that the synergistic effect between the two components of the composite material not only enhance the snow-melting and de-icing performance of the asphalt pavement but also prolong the snow-melting time of the pavement in a low-temperature environment.

Performance evaluation of flexible pavement using polyethylene terephthalate (PET)

In this study, the benefits and feasibility of incorporating Polyethylene Terephthalate (PET) into Flexible pavement were evaluated. The study aims to identify new ideas on recycling plastic wastes and thereby improving overall sustainability. The Samples were prepared by adding PET with an increasing concentration level along with optimum asphalt content with a percentage by weight of 3.5%, 4.0%, 4.5%, 5.0%, 5.5% and 6%. Multiple tests were conducted on Natural aggregates including Resistance to degradation of aggregates by Abrasion and Impact, Specific Gravity and Abrasion of coarse aggregates, and Impact Value of Aggregates. Similarly, the tests conducted on asphalt include the specific gravity of semi-solid bituminous material, the ductility of bituminous material, the flash point and softening point of asphalt, and the penetration grade of bituminous material. Rutting potential of the optimum asphalt, Plastic mix Was evaluated by increasing the frequency of load cycles from 0 to 5000 cycles. Furthermore, the effect of asphalt and plastic content on the density, Flow, voids, and stability were also analysed. It was found that the addition of PET resulted in improved stability by more than 50% specifically 52%, while 70% improvement was observed in flow characteristics of Hot Mix Asphalt. However, a slight change in density was observed. The sample also showed a reduction in rut depth by more than 40% of the mix.

The Impacts of Red Mud on Road Performance and Aging Resistance of Asphalt Mixture

Abstract Red mud as an asphalt modifier has been investigated in some studies, but few studies are further concerned about the effect of red mud on performance of asphalt mixture. In this study, the impact of red mud on road performance and aging endurance of asphalt mixtures was evaluated. Primarily, the optimal asphalt content was determined based on mechanical strength and volumetric properties. Then, the performance evaluations, including Marshall stability, low-temperature splitting, freeze-thaw splitting, indirect tensile fatigue, and thermal-oxidative aging, were executed. The outcomes demonstrate that in comparison with the base asphalt mixture, red mud asphalt mixture exhibits worse high-temperature stability and moisture resistance, and superior temperature shrinkage cracking resistance and fatigue performance. After the surface of red mud has been modified, the adhesion between asphalt mastics and aggregate is strengthened, and the distribution of red mud in asphalt mixture becomes more uniform, which intensifies the rigidity and road performance (except for low-temperature cracking resistance) of asphalt mixture. Furthermore, since red mud absorbs a portion of asphalt content, it can hinder the physical hardening and oxidation rate of asphalt mixture. The anti-aging ability of asphalt mixture is further reinforced by the incorporation of organic red mud.

Utilization of Palm Shell Ash as a Filler in Making AC-WC Type Porous Asphalt

The background to the research that will be carried out is that the large amount of standing water on the road pavement in each rainy season results in disturbances to motorists' comfort. This is due to impermeable road pavement and poor drainage along the road. Porous asphalt can increase rainwater absorption, thereby reducing puddles on the road surface. Porous asphalt is a new breakthrough in the world of road pavement to reduce the appearance of puddles of water when it rains. Porous asphalt is also designed to have high porosity so that water can flow through side channels and a waterproof base layer to prevent water from seeping into the subbase layer and road body so as to minimize puddles of water on the road surface which often occur after rain and disrupt the smooth flow of traffic. cross. Advances in road pavement technology have encouraged researchers to conduct research using palm shell ash (fly ash) as a filler in porous asphalt mixtures. The use of palm shell ash is expected to increase the stability value and have large cavities so that water can pass through the road surface, as well as to reduce palm oil waste in Indonesia. The objectives of this research are 1. To find out the optimum asphalt content value in porous asphalt mixtures, 2. To know the results of using palm shell ash at 0%, 1% and 2% as a filler for porous asphalt mixtures in flexible road pavement. The research method is Marshall and Permeability Testing. The tests that will be carried out on a laboratory scale use an AC-WC hot mix asphalt system with guidance, namely the basics of asphalt concrete road construction. The research results showed that by adding palm shell ash as a filler in making AC-WC type porous asphalt, it showed that the stability value was higher, while the permeability value was lower, meaning that the addition of palm shell ash to the porous asphalt mixture did not have a significant effect because it was smaller. air voids in the mixture. The addition of palm shell ash to the porous asphalt mixture increases the stability value which can increase the ability of road construction to accept loads, but the pavement layer is not permeable and water flows over the surface more slowly.

Optimization and pavement performance of buton-rock-asphalt modified asphalt mixture with basalt-fibre

To optimise the mechanical performance of a buton-rock-asphalt (BRA)- modified asphalt mixture with basalt-fibre (BF), the optimum contents of BF and BRA, as well as the optimal asphalt stone ratio were obtained using response surface methodology (RSM). The feasibility of the mixed-ratio optimised design method was verified via a Marshall stability test. The results indicated that the optimal BF, BRA and asphalt stone ratios were 0.324 %, 22.44 % and 5.23 %, respectively. Moreover, there were some deviations between the average and predicted values of each response index. However, the error range was less than 5 %. A pavement performance index paired comparison matrix calculation method was established, and the pavement performance of the BF-BRA modified asphalt mixture was evaluated using the analytic hierarchy process (AHP). The process comprised eight different content combinations of BF and BRA. The maximum values of dynamic stability, bending strain, immersion Marshall residual stability, and tensile strength ration of BF-BRA modified asphalt mixture were 6512 cycles/mm, 4091 με, 97.4 %, 96.2 % respectively. This indicated that the pavement performance of asphalt mixture can be improved effectively by adding BF and BRA. Additionally, the BF-BRA modified asphalt mixture, which scored highest in pavement performance as evaluated by AHP, aligned with results obtained through response surface methodology(RSM) optimization. This consistency indicates that the BF-BRA modified asphalt mixture derived from RSM exhibits the best pavement performance.