Evaluation of the moisture damage susceptibility and the rutting resistance of natural bitumen mixture: An experimental investigation

As a hydrocarbon-rich byproduct of petroleum systems, natural solid bitumen demonstrates dual dissolution and adsorption functionalities toward liquid hydrocarbons. Elucidating these adsorption mechanisms provides critical insights into hydrocarbon expulsion dynamics during bitumen secondary cracking and informs strategies for fluidity modulation. This molecular-scale investigation systematically examines interfacial binding mechanisms governing bitumen-hydrocarbon interactions. Building upon atomistically resolved models, semi-flexible docking simulations were conducted across hydrocarbon compound classes and thermal maturation stages. Quantitative analysis of binding Gibbs free energy differentials between saturated and aromatic hydrocarbons revealed distinct interaction modalities governing solid-liquid organic interfaces. These interfacial interactions exhibit four governing parameters: hydrocarbon type, molecular weight, methyl group density at organic interfaces, and condensation degree. High molecular weight polycyclic aromatic hydrocarbons with elevated condensation degrees and their derivatives display enhanced binding affinities, contrasting with the weak retention observed for light hydrocarbons, small cycloalkanes, and low-weight aromatic species.

With the continuous advancement of green mining initiatives in China, dust control during coal mining has become a critical issue for occupational health and ecological environmental safety. In response to the issues of coal dust pollution generated during coal mining and the inefficiencies of water spray dust suppression, this study investigates the fundamental mechanism by which multi-component surfactants synergistically form a stable adsorption layer on bituminous coal surfaces. The research employs macro-scale surface tension measurements, dynamic contact angle analysis, XPS spectroscopy, SEM for microstructural morphology, and molecular dynamics simulations. The results identify the optimal formulation as a 1:1 volume ratio mixture of 0.2% SDS and 0.1% CDEA. The synergistic effect of hydrogen bonding and electrostatic interactions first promotes the formation of a complex between the sulfate group of SDS and the amide group of CDEA. This complex then packs more efficiently, leading to an increased molecular density at the interface. The surface tension of the system is reduced to 35.23 mN/m, while the adhesion work and immersion work of the solution on the bituminous coal surface reach their maximum values. The spreading work is -0.48 mN/m, closest to the threshold of spontaneous spreading. This research offers theoretical support for developing a new generation of high-performance and environmentally friendly dust suppressants.

Abstract Abstract: Flexible pavements with bituminous surfacing are widely used in India. Exponential increase in traffic, overloading of commercial vehicles and variations in temperatures have shown some limitations of conventional bitumen performance. Flexible pavements can be defined as the one consisting of a mixture of asphaltic or bituminous material and aggregates placed on a bed of compacted granular material of appropriate quality in layers over sub-grade. Bituminous surfacing develops distress symptoms like cracking, rutting, raveling, undulations, shoving etc, are been reported in flexible pavements. Bitumen modified with Styrene Butadiene Rubber (SBR) which is one of the most effective polymer additive offers a combination performance related to physical properties of the bitumen. SBR is an elastomer which is an important sort of synthetic rubber whose molecule structure primarily consists of organic compound Styrene and Butadiene chain. It plays an active role in improving the visco-elastic properties bitumen and also changes rheological behavior of bitumen by increasing the resistance of mixture against permanent deformations. This paper presents the experimental study on modification of Bitumen by the replacement of bitumen by SBR latex at 0, 3, 5, 7, 9% by the weight of bitumen. Various tests on bitumen like penetration test, softening point, viscosity test and ductility test are conducted on addition of SBR latex with bitumen and results are compared. Marshall Stability test is the one of the important test conducted to decide the performance of the bituminous mix. So, Marshall Stability test is conducted for various percentages of SBR latex and optimum % is determined. The properties of the mix evaluated by Marshall test are stability, flow, air voids (Va), volume of mineral aggregates (VMA) and void filled with bitumen (VFB). From this test optimum content of SBR to be added to bitumen is obtained. SBR latex is an easily available product and also economical. Keywords: Bitumen, SBR latex, Marshal Stability test, visco-elastic.

Abstract - The growing demand for road infrastructure has intensified the need for sustainable and resource-efficient construction practices. Conventional flexible pavements predominantly depend on non-renewable materials such as natural aggregates and bitumen, whose large-scale extraction leads to environmental degradation. At the same time, the rapid accumulation of plastic waste and quarry dust has emerged as a major ecological concern due to improper disposal practices. Addressing these dual challenges, the present study explores an innovative and environmentally responsible approach by utilizing shredded waste plastic as a partial replacement for bitumen and quarry dust as a supplementary mineral filler in bituminous mixes. The materials were selected considering their physical, chemical, and environmental attributes, along with their wide availability. A comprehensive laboratory program—including Marshall Stability, California Bearing Ratio (CBR), moisture susceptibility, and volumetric property analyses—was conducted to evaluate the performance of modified mixes with varying proportions of waste plastic and quarry dust. The experimental results demonstrate that incorporating waste plastic significantly enhances the binding capacity, stiffness, and rutting resistance of the pavement mix, contributing to improved strength and durability. Quarry dust, when used as a filler, effectively increases mix density, reduces air voids, and enhances the overall stability of the bituminous layer. The modified mixes exhibited superior load-bearing capacity, greater resistance to moisture-induced damage, and improved structural performance compared to conventional mixes. Overall, the integration of waste plastic and quarry dust promotes sustainable pavement construction by reducing environmental pollution, minimizing reliance on natural resources, and supporting the principles of green engineering and circular economy in civil infrastructure. Key Words: Flexible pavement, waste plastic modification, quarry dust filler, Marshall Stability, CBR, moisture susceptibility, sustainable pavement materials, bituminous mix design, rutting resistance, green engineering.

The wettability of bituminous coal surfaces in the presenceofnonionic surfactants was investigated to understand the underlyingmechanisms of surfactant interaction. Using raw coal from the Pingdingshanmining area, this study employed comprehensive characterization techniques,including proximate analysis, FTIR, 13C NMR, and XPS toexplore the structural parameters of the bituminous coal. These techniquesprovided insights into the surface functional groups, elemental composition,and carbon skeleton, which facilitated the construction of a macromolecularstructural model. Wettability experiments, such as sedimentation time,Zeta potential, and surface free energy measurements, were conductedto evaluate the effect of nonionic surfactants (JFC-E, X-100) on coaldust wettability. The combination of laboratory experiments and molecularsimulations with self-developed coal macromolecular model enableda deeper understanding of the molecular-scale interactions betweenthe surfactants and coal. The results demonstrated that Pingdingshanbituminous coal is primarily composed of hydrophobic aromatic hydrocarbons,with benzene, naphthalene, and anthracene as the key aromatic units.Surfactant adsorption was found to significantly alter the coal’ssurface free energy, enhancing the polar component, with X-100 exhibitingoptimal performance. Molecular simulations revealed that X-100’shydrophilic moiety contains more oxygen-containing functional groupsthan JFC-E, providing additional hydrophilic sites. Furthermore, X-100’sbenzene ring structure strengthens π–π interactionswith the coal surface, leading to a more stable adsorption configurationthat facilitates water molecule adsorption. This study provides technicalguidance and methodological insights for scientifically efficientdust suppression in mining operations.

To date, there has been continued demand for more effective, less expensive, and accessible coating systems for durable corrosion and wear protection of auto-bodies, with a research need to meet the demands. The rationale behind this study was to create a high-quality, low-cost bituminous paint for use in protecting the underparts of automobile chassis against corrosion and wear, particularly in Nigeria. Five paint blends containing various proportions of 70–100% Agbabu natural bitumen, 02–5% kerosene, 0–8.5% cobalt, 0–1% pigment, and 0–2.1% lead drier were produced and characterized by their basic physicochemical properties. The blends were brush-coated to a 1.78-mm average thickness on plate samples of mild steel, a commonly and widely applied but highly corrosion-susceptible chassis material type. Corrosion and wear tests performed on the steel samples under 1.78-mm-thick hard-dried coatings of the paint blends revealed that the blend with 75% bitumen, 15% kerosene, 8% cobalt, 0.6% pigment, and 1.4% lead drier content could perform exceptionally well in protecting the steel at the coating thickness. X-ray fluorescence and scanning electron microscopy analyses of that paint blend were conducted to understand its distinct chemical compositions and microstructural homogeneity level. The 1.78-mm-thick coatings of that paint blend's adhesion adequacy to the steel was also investigated. Analyses of the collected data revealed that the blend contained 25 different chemical species that are benign to steel corrosion, had a more or less uniform microstructure demonstrating its homogeneity, had minimal interangular boundaries indicating minimal ingress of corrosion-causing agents to the steel underneath its coatings, and its hard-dried thin coatings would have excellent adhesion to any ferrous chassis material.

Evaluation of biosurfactant wettability on bituminous coal surface: An integrated experimental and molecular dynamics simulation study

This article explores effective technological approaches for processing natural bitumens found in the Zhylyoi district, based on their physicochemical properties and organic composition. Natural bitumens, as organic components of oil-bituminous rocks, represent a promising source of hydrocarbon raw materials. The study investigates the group chemical composition and distribution of functional groups in bitumens from the Jusalyssay, Kölzhan, and Tüpkaragan deposits. Results indicate significant concentrations of paraffin-naphthenic hydrocarbons, mono- and polycyclic aromatic compounds, resins, and asphaltenes. The relative proportions of these components play a decisive role in selecting appropriate processing methods. Three main technological pathways are proposed: physical (vacuum distillation, deasphalting, demetallization), thermal (coking, cracking), and catalytic (hydrotreatment). The article also substantiates the economic feasibility of locating processing plants near natural bitumen deposits. Processing schemes based on oil-bitumen and fuel-coke directions are presented, demonstrating their potential to expand product range and improve quality. The findings offer scientifically grounded strategies for the integrated processing of natural bitumens and their efficient industrial utilization.

Optimizing pavement maintenance and rehabilitation (M&R) strategies is essential, especially in developing countries with limited budgets. This study presents an integrated framework combining a deterioration prediction model and a genetic algorithm (GA)-based optimization model to plan cost-effective M&R strategies for flexible pavements, including asphalt concrete (AC) and double bituminous surface treatment (DBST). The GA schedules multi-year interventions by accounting for varied deterioration rates and budget constraints to maximize pavement performance. The optimization process involves generating a population of candidate solutions representing a set of selected road sections for maintenance, followed by fitness evaluation and solution evolution. A mixed Markov hazard (MMH) model is used to model uncertainty in pavement deterioration, simulating condition transitions influenced by pavement bearing capacity, traffic load, and environmental factors. The MMH model employs an exponential hazard function and Bayesian inference via Markov Chain Monte Carlo (MCMC) to estimate deterioration rates and life expectancies. A case study on Cambodia’s road network evaluates six budget scenarios (USD 12–27 million) over a 10-year period, identifying the USD 18 million budget as the most effective. The framework enables road agencies to access maintenance strategies under various financial and performance conditions, supporting data-driven, sustainable infrastructure management and optimal fund allocation.

Background: With light oil reserves depleting and the demand for lubricants steadily increasing, the development of alternative sources of hydrocarbon feedstock has become a pressing issue. Despite the technological complexity of processing, natural bitumens represent a promising raw material for the production of base oils, particularly in the Republic of Kazakhstan, where domestic industrial lubricant production is currently absent. Aim: To assess the possibility of obtaining base industrial and motor oils from oil fractions derived from the fuel oil of natural bitumen at the Karasaz-Taspas deposit. Materials and methods: on the study object was fuel oil obtained by atmospheric distillation of natural bitumen. Oil fractions with boiling temperature ranges of 350–400 °C and 400–460 °C were separated using vacuum distillation. Purification was carried out using bleaching clay. The physical and chemical characteristics of the fractions were determined before and after purification according to standard ASTM and GOST methods. Results: The obtained oil fractions are characterized by a high kinematic viscosity, a viscosity index of up to 110.7, and low sulfur content (0.45 wt.%). Their physical and chemical properties meet the requirements for base oils of groups I and II according to the American Petroleum Institute classification and are comparable to industrial oils of grades I-40A and I-50A. Dewaxing and the addition of additives are necessary to improve low-temperature performance. Conclusion: Natural bitumen from the Karasyaz-Taspas deposit is a promising raw material for producing high-quality base oils. The study confirms the feasibility of comprehensive processing of natural bitumen fuel oil to produce industrial and motor oils, contributing to the replenishment of the raw material base, the sustainable development of the oil industry, and the enhancement of the country’s energy security.

Research subject. Bituminous sandstones of the Sheshmian horizon of the Ufimian stage in the Republic of Tatarstan.Aim. To identify relationships between lithological and petrophysical parameters for paleoreconstructions of the conditions of formation and redeposition of natural bitumen deposits.Materials and methods. The composition and internal structure of bituminous sandstones were studied by optical microscopy methods (petrographic description of thin sections) and thermogravimetry (quantitative parameters of oil saturation and carbonation), statistical processing of the results of granulometric and petrophysical analyses in Statistica 10 software.Results. The studied sandstones belong to the graywacke group. Statistical analysis of granulometric and filtration-capacity parameters of bituminous sandstones revealed relationships between certain fractions and the degree of bituminosity. Cluster and factor analysis of lithologic and petrophysical data made it possible to identify integral indicators that can be used to reconstruct the paleofacies of the Sheshmian sandstones. The important role of the Sheshma River valley in the reformation of bitumen deposits in the Neogene-Quaternary time under the influence of Coriolis force has been established. Presence of soda water with high (more than 1 g/l) content of hydrocarbonate-ion is a hydrochemical criterion for searching the deposits of natural bitumen. The present study complements the existing hypotheses of the formation of the Sheshmian bituminous sandstones of the South Tatar arch.Conclusion. Based on a combined analysis of geological data, lithological and petrophysical parameters, it is suggested that the most bitumen-saturated upper layer of sandstones was formed by eolian processes.

Low-temperature coal tar (LTCT) is the preferred rawmaterial forthe catalytic hydrogenation of coal tar. In order to study and popularizethe technology of preparing fuel oil by hydrogenation of LTCT, itis necessary to research its composition and structural characteristics.Heavy hydrogenated coal tar (HHCT) from a company in Xinjiang, whichis a mixture of hydrorefined tail oil distillate (>350 °C)andhydrotreated circulating tail oil (>350 °C). To make scientificand customized use of HHCT, the chemical composition and molecularstructure characteristics of HHCT and its subcomponents were investigatedby using elemental analysis (EA), infrared analysis (FT-IR), and nuclearmagnetic resonance (1H NMR and 13C NMR) throughfraction separation. Compared to other low-temperature coal tar (LTCT),the content of saturates (SA) in HHCT is 95.01 wt %, considerablyhigher than other LTCT samples, and the content of aromatics (AR),resins (RE), and asphaltenes (AS) is all much lower than other LTCTsamples. Compared with the basic properties, elemental content, andrefining performance of other crude oils, HHCT is good-quality oilwith relatively small density, high H/C ratio, fewer heteroatoms,and low metal impurities, and is easy to refine and process. FT-IRand NMR results show that HHCT and SA are primarily constituted oflong-chain n-alkanes possessing longer aliphaticchains and fewer branched chains. Aromatics are predominantly presentin AR and mainly encompass bicyclic and tricyclic aromatics. HHCTand other fractions contain a small quantity of aromatic structures.

Abstract In Canada, companies mining bitumen must restore landscapes to self‐sustaining boreal ecosystems. Residual hydrocarbons can be present in some reclaimed landforms, and their potential effect on vegetation is unclear. In this region, forests occur on natural surficial bitumen deposits, and vegetation persists on bitumen ore piles that have since been abandoned by industry. We investigated whether practitioners can leverage plant–soil interactions that enable vegetation to grow in bituminous soils to facilitate the establishment of tree seedlings on reclaimed sites containing residual hydrocarbons. We characterized soil fungal communities using Illumina Mi‐Seq sequencing across field sites with varying hydrocarbon levels, focusing on fungi due to their potential effects on seedling performance. We then used soil from these sites as inoculum in a growth chamber experiment, adding it to five substrates, in which we grew jack pine ( Pinus banksiana Lamb.) and trembling aspen ( Populus tremuloides Michx.). Three of those substrates were sympatric to the inoculum, and the other two were reclamation materials differing in hydrocarbon concentrations. The field sites differed in fungal community composition, and the abandoned ore pile had the most distinct fungal community. We found that substrate type affected aspen seedling growth independent of inoculum source. In contrast, the effect of substrate type on pine seedling growth depended on the source of inoculum. Specifically, inoculum from the abandoned ore pile increased pine growth by up to 128% in one of the reclamation substrates tested. However, this same inoculum decreased or had no effect on aspen seedling growth across the substrates. The low colonization of roots by mycorrhizal fungi suggests that other microbes may underlie seedling responses. Synthesis and applications . Soil inoculation improved tree seedling growth in some substrates containing bitumen, but the effect varied by species and inoculum source. Inoculum from extreme environments, such as the abandoned ore pile, may harbour microbes effective in supporting pine seedling growth in soils with residual hydrocarbons. Testing this inoculum source in field trials would be the next step in evaluating its use in promoting pine seedling establishment on reclaimed sites.

In the current study, a breakthrough methodology has been utilized to deliver polymer composites based on polystyrene (PS) with enhanced optoelectronic properties. In this work, bitumen (BT), which is enriched with hydrocarbons and N/O elements extracted from natural rocks, has been employed to alter the optical band gap of the PS polymer. It was found that the optical parameters of PS improved significantly, which is crucial from the technological application viewpoint. The PS: BT films have been prepared utilizing a simple solution casting method. Fourier transforms infrared (FTIR), Raman spectroscopy, UV-absorption spectroscopy, and X-ray diffraction were used to investigate the effect of (BT) loading on the structural and optical properties of PS. The XRD analysis revealed that the addition of BT into PS improved the crystalline phase structure for the composite films. The D and G bands related to order and disorder structures were distinguished in the Raman spectra of the bitumen. The FTIR spectra demonstrated a shift and constriction of the PS-O-H stretching bands upon incorporating BT, indicating a robust interaction between BT and the polymer matrix. Furthermore, the FESEM images revealed rough surfaces in the composite films. Optical characterizations reveal that integrating BT into PS films enhanced their reflectance and diminished their transmittance of incident light at visible and ultraviolet wavelengths. The optical properties, including the absorption edge, refractive index, and dielectric constant, encompassing both the real and imaginary parts, were analyzed. The dielectric constant increased when comparing the composite samples to the pure polystyrene sample. The optical energy gap dropped from 4.34 to 1.14 as the BT doping concentration increased to 2 mL. The band edge width, which characterizes the tail-localized states, increases with higher BT concentration. The results of the present work will revolutionize the field of polymer composites for photonics and optoelectronics, especially non-linear optics and laser attenuation.

This study investigates how cycling speeds vary across infrastructure types using open data from Hamburg, Germany, collected between 2022 and 2024. By integrating bicycle network data, tracking app-based cycling speeds, land use, and topographic information, key determinants of cycling speed are identified through a gamma regression model. Results show that infrastructure type, surface conditions, and surrounding land use significantly affect speed. Dedicated cycling infrastructure promotes faster and more consistent speeds, especially on bituminous surfaces. Also, longer segments increase speeds. Urban or industrial areas tend to reduce speeds, while fields and forests lead to faster cycling speeds.

Purpose: The purpose of this study is to assess the performance of double bituminous surface treatment on the Malekhu–Dhading Beshi (MDB) Road in Nepal-Asia. Design/Methodology/Approach: The descriptive study was conducted to evaluate the compatibility of the road condition assessment method for analysing results and assessing road conditions between 2012 and 2021. The assessment method consists of the International Roughness Index (IRI), the Surface Distress Index (SDI) and the Pavement Serviceability Rating (PSR). The correlation between SDI and IRI, SDI and Average Annual Daily Traffic (AADT), IRI and AADT, SDI and Age of pavement, and IRI and Age of pavement were obtained from the correlation analysis. Research Limitation: The study lacked adequate data on the quality and availability of the performance of the road projects and the delays in the study area. Findings: The relation between IRI-Traffic and SDI-IRI is positive, with R2 values of 0.0713 and 0.6831, respectively. The relation between IRI and Traffic is poor, and the relation between SDI and IRI is good. The relation between SDI-Traffic and SDI-Age of pavement is logarithmic, with R2 values of 0.4786 and 0.4319, respectively, which is a moderate relationship. The relation between the Ages of pavement and IRI is polynomial with an R2 value of 0.2676, indicating a poor relationship. Pavements in this category (value of PSR between 1.00 and 2.00) have deteriorated to such an extent that they affect the speed of free-flow traffic. Practical Implication: Understanding performance characteristics enables the strategic timing of applications, the selection of appropriate treatment types, and the prediction of maintenance cycles. This leads to a more efficient allocation of public resources and extended pavement life cycles. Social Implication: Enhanced road surfaces facilitate emergency vehicle access, school bus transportation, and agricultural product movement, directly impacting quality of life and social equity. Originality/Value: This pavement deterioration model can be used for the forecast of future values of IRI. This model is the basis for the assessment of Double Bituminous Surface Treatment pavement.

The vast majority of road infrastructure deformations are irreversible. They shorten the lifespan of flexible pavements and add to road safety concerns. Viscoelasticity is required for natural bitumen to function as a binder in pavements. However, when exposed to climate and heavy loads, natural bitumen's ability to undergo elastic deformation reduces. Consequently, road researchers have focused on modifying bitumen using polymers and nanomaterials to enhance pavement performance. Polymeric bitumen is extremely sensitive to Polypropylene (PP) dosage. Excessive use of PP leads to high viscosity. This study examines the impact of PP doses on the physical, rheological, and mechanical properties of Agbabu natural bitumen. The bitumen was dehydrated and analyzed for conventional characteristics using established techniques. The purified material was treated with PP at varying dosages (1.5 - 6 wt percent), and a binary mixture of bitumen and PP was optimized using D-Optima experimental design and response surface approach. The result shows that the mechanical properties, flash, and softening points of the raw bitumen were enhanced after modification. However, the penetration point of the modified bitumen decreases while viscosity increases as PP dosage increased from 2 to 3.75 wt percent. Therefore, the optimum dosage of 2.75 wt percent PP is recommended.

As conventional hydrocarbon resources become depleted, there is growing interest in developing unconventional sources of raw materials, such as natural bitumen (NB) and oil-bituminous rocks (OBR). This article presents the results of comprehensive scientific research into the physical and chemical properties and composition of the natural bitumen found in the Karasyaz-Taspas field in Mangistau, Kazakhstan, and the development of effective technological solutions for its processing. A comprehensive analysis of the elemental, group and fractional composition of the natural bitumen was carried out. On the basis of this analysis, the technological value of the natural bitumen as a raw material for obtaining a wide range of target products, such as fuel distillates, base oils and construction bitumen, was established. Based on experimental data, the effectiveness of extracting natural bitumen using a nitrite composition has been demonstrated, as has the potential of distillate and residual products. Distillate fractions were found to be suitable for use as components of motor fuels and lubricants, while residual products were found to be suitable for the production of road and construction bitumen. Technological solutions for the complex processing of natural bitumen have been developed and put forward. The results obtained confirm the potential for the integrated development of Kazakhstan’s oil-bituminous rock reserves as a valuable source of hydrocarbons, opening up opportunities to expand the raw material base and promote the development of the Republic of Kazakhstan’s petrochemical industry.

Asphalt is widely used in road pavement construction to bind aggregates. Road surface distress occurs when there is a sign of poor pavement performance. Therefore, asphalt modification is sometimes used to improve its performance. This study was carried out to investigate the use of Polyethylene Terephthalate (PET) to modify bitumen in Hot Mix Asphalt (HMA). The optimum bitumen content (OBC) for mixed design was determined, and the modified HMA was prepared by replacing the OBC with 2, 4, 6, 8, and 10% PET. The effect of PET on HMA was examined. The OBC was 6%. The addition of PET changed the penetration grade from 60/70 to 50/60 at 6% PET replacement, and an improvement in marshal stability was noticed as PET content increased. An increase in void in mix, and a reduction in the bulk density of the modified HMA were observed as PET content increased up to 6%. The modified HMA developed more resistant to deformation with an increase in Marshall Quotient as PET content increased up to 6%, and had more potential to resist moisture damage. This study revealed that HMA with bitumen modified with 6% PET waste is suitable for pavement construction.