applsci-logo

Journal Browser

Journal Browser

Recent Advances in Asphalt Materials and Their Applications

A special issue of Applied Sciences (ISSN 2076-3417). This special issue belongs to the section "Civil Engineering".

Deadline for manuscript submissions: 20 June 2025 | Viewed by 4491

Special Issue Editor


E-Mail Website
Guest Editor
Department of Civil and Environmental Engineering, Michigan State University, East Lansing, MI, USA
Interests: pavement management preservation evaluation and design
Special Issues, Collections and Topics in MDPI journals

Special Issue Information

Dear Colleagues,

Granular layers, comprising unbound aggregates, are placed on top of the subgrade to provide stability, drainage, and support to a pavement system. Given the range of aggregate types available for a pavement’s granular layer construction, an appropriate choice depends on various factors such as availability, intended use, material properties, short- and long-term performance requirements, environmental issues, sustainability, and cost-effectiveness. Much research in the past has focused on gaining a better understanding of the mentioned factors, with a particular view to virgin aggregate (VA). It has enabled transportation agencies to establish standards and guidelines for pavement construction in different regions and facilitates further studies for refined insights.

Recycled concrete aggregate (RCA) is a type of aggregate produced after the dismantling of concrete pavement and structures. Though recent studies have demonstrated that RCA exhibits superior strength to VA when used in granular layers of pavements, further investigation is needed to address the hydrophilic nature and slow hydration process of cementitious materials. In contrast, reclaimed asphalt pavement (RAP) aggregates display hydrophobic characteristics; however, the asphalt coating of the aggregate may cause softening in warm climates and resultantly prove counterproductive for use in pavements.

The use of steel slag in the unbound layers has also been a research topic in the recent past. Where it offers improved strength and durability, potential environmental concerns, including the leachate of heavy metal contamination, need to be addressed further. Crushed brick is another recycled material that can replace VA in sub-base layers. It may stabilize a pavement system in some cases, but further durability analyses are needed to ensure its effectiveness.

The research community has recently devoted much attention to mechanical methods with which to support unbound material in granular layers. Studies are presenting the benefits of using geosynthetics in pavement construction. In this context, future research may propose different designs and installation techniques with which to reduce financial costs and enhance performance. Studies may also focus on comparing the available types of materials and consider incorporating newer technologies.

Future research may emphasize developing testing protocols, suggesting construction procedures, creating optimum gradation tools, proposing blends of different materials, and assessing long-term performance regarding alternate aggregate types. It can also incorporate techniques to stabilize granular layers, e.g., lime-related additives, salts, and plastic fines; however, studies regarding chemical stabilization techniques must always consider environmental aspects and requisite solutions, as the possible leaching of harmful elements can pollute the surrounding environment.

Prof. Dr. Syed Waqar Haider
Guest Editor

Manuscript Submission Information

Manuscripts should be submitted online at www.mdpi.com by registering and logging in to this website. Once you are registered, click here to go to the submission form. Manuscripts can be submitted until the deadline. All submissions that pass pre-check are peer-reviewed. Accepted papers will be published continuously in the journal (as soon as accepted) and will be listed together on the special issue website. Research articles, review articles as well as short communications are invited. For planned papers, a title and short abstract (about 100 words) can be sent to the Editorial Office for announcement on this website.

Submitted manuscripts should not have been published previously, nor be under consideration for publication elsewhere (except conference proceedings papers). All manuscripts are thoroughly refereed through a single-blind peer-review process. A guide for authors and other relevant information for submission of manuscripts is available on the Instructions for Authors page. Applied Sciences is an international peer-reviewed open access semimonthly journal published by MDPI.

Please visit the Instructions for Authors page before submitting a manuscript. The Article Processing Charge (APC) for publication in this open access journal is 2400 CHF (Swiss Francs). Submitted papers should be well formatted and use good English. Authors may use MDPI's English editing service prior to publication or during author revisions.

Keywords

  • unbound materials
  • asphalt
  • recycled concrete aggregates
  • aggregate base
  • sub-base
  • stabilization
  • durability
  • moduli

Benefits of Publishing in a Special Issue

  • Ease of navigation: Grouping papers by topic helps scholars navigate broad scope journals more efficiently.
  • Greater discoverability: Special Issues support the reach and impact of scientific research. Articles in Special Issues are more discoverable and cited more frequently.
  • Expansion of research network: Special Issues facilitate connections among authors, fostering scientific collaborations.
  • External promotion: Articles in Special Issues are often promoted through the journal's social media, increasing their visibility.
  • e-Book format: Special Issues with more than 10 articles can be published as dedicated e-books, ensuring wide and rapid dissemination.

Further information on MDPI's Special Issue policies can be found here.

Published Papers (3 papers)

Order results
Result details
Select all
Export citation of selected articles as:

Research

Jump to: Review

15 pages, 2137 KiB  
Article
Ecological Concrete-Based Modular System for Heavy Metal Removal in Riparian Transition Zones: Design, Optimization and Performance Evaluation
by Guangbing Liu, Da Ke, Hasnain Moavia, Chen Ling, Yanhong Zhang and Yu Shen
Appl. Sci. 2025, 15(7), 3721; https://doi.org/10.3390/app15073721 - 28 Mar 2025
Viewed by 235
Abstract
This study presents the development and evaluation of an innovative modular ecological transition zone system for riparian restoration. Through systematic optimization, we developed a C25-grade ecological concrete module (100 mm × 100 mm × 100 mm) with a specialized cavity design (φ61 mm [...] Read more.
This study presents the development and evaluation of an innovative modular ecological transition zone system for riparian restoration. Through systematic optimization, we developed a C25-grade ecological concrete module (100 mm × 100 mm × 100 mm) with a specialized cavity design (φ61 mm × H60 mm) that achieves optimal balance between structural integrity (20–30 MPa compressive strength) and environmental functionality (>15% porosity, >1 × 10−4 cm s−1 permeability). The module incorporates precisely calibrated proportions of cement (378 kg m−3), reinforcing agent (12 kg m−3), aggregate (1650 kg m−3), and water (137 L m−3), creating a robust platform for environmental remediation. The system was evaluated at two scales: module-scale experiments in 25 L containers (833:1 mL g−1 ratio) and kinetic studies (10:1 mL g−1 ratio), revealing a sophisticated three-phase removal process. The initial rapid surface adsorption phase (0–4 h) achieved removal rates of 0.28–0.42 mg g−1 h−1, followed by pore diffusion (4–24 h) and chemical fixation phases, with removal patterns effectively modeled using a modified pseudo-second-order equation. The system demonstrated exceptional heavy metal removal capabilities across varying concentration ranges, achieving removal efficiencies of 95.6% for Pb2+ ions, 92.3% for Cd2+ ions, 84.2% for Cr3+ ions, 89.7% for Cu2+ ions, and 84.8% for Zn2+ ions under optimal conditions. Performance remained robust across two orders of magnitude in concentration ranges, with removal efficiencies maintaining above 80% at both experimental scales. The modular design’s cost-effectiveness is demonstrated through material costs of USD 45–60 m−3, with operational costs 40–60% lower than conventional systems. This research provides a practical, cost-effective solution for riparian zone restoration, combining structural durability with efficient pollutant removal capabilities while maintaining consistent performance across varying environmental conditions. Full article
(This article belongs to the Special Issue Recent Advances in Asphalt Materials and Their Applications)
Show Figures

Figure 1

16 pages, 3160 KiB  
Article
Comparison of Lab vs. Backcalculated Moduli of Virgin Aggregate and Recycled Aggregate Base Layers
by Qasim Zulfiqar, Syed Waqar Haider, Bora Cetin, Haluk Sinan Coban and Seyed Farhad Abdollahi
Appl. Sci. 2024, 14(19), 9049; https://doi.org/10.3390/app14199049 - 7 Oct 2024
Viewed by 1148
Abstract
The resilient modulus (MR) and the backcalculated modulus from the FWD testing (EFWD) of the unbound layers are critical inputs in the analysis/design of pavements. Several studies have tried to develop a conversion factor between these two [...] Read more.
The resilient modulus (MR) and the backcalculated modulus from the FWD testing (EFWD) of the unbound layers are critical inputs in the analysis/design of pavements. Several studies have tried to develop a conversion factor between these two parameters, while the nonlinear stress dependency of unbound materials and the pavement strain response are mostly missing from the literature. This study aims to compare the laboratory-measured MR of recycled aggregate base (RAB) materials and a virgin aggregate base using field-based EFWD and tries to establish pavement’s responses to loading using vertical strains from both the MR and EFWD values of the respective materials as comparability parameters between the two. For this purpose, a control virgin aggregate (VA, limestone) and three types of RAB materials were selected to construct four test sections. The test sections were modeled in layered elastic- and finite-element-based pavement response models to calculate the vertical strains at the mid-depth of the base and top of the subgrade layers. A comparison of the lab-calculated vertical strains using MR with actual vertical strains in the field from EFWD showed that there was no relationship between the two stiffness parameters in all tested RABs. The vertical strains, based on the lab MR, undermined the stiffness of the recycled aggregates in the field. In contrast, the values of EFWD based on the vertical strains remained close to the MR strains of limestone (VA) throughout the testing period, establishing an EFWD vs. MR relationship (MR = 0.87 EFWD). The results also show that fine RCA was a better-performing material over three years. This research not only explores how the hydration process in RABs limits the development of MR-EFWD correlations but also underscores the need to consider real-world conditions when assessing their performance. Full article
(This article belongs to the Special Issue Recent Advances in Asphalt Materials and Their Applications)
Show Figures

Figure 1

Review

Jump to: Research

15 pages, 1613 KiB  
Review
A Review of Sustainable Pavement Aggregates
by Jaime R. Ramírez-Vargas, Sergio A. Zamora-Castro, Agustín L. Herrera-May, Luis C. Sandoval-Herazo, Rolando Salgado-Estrada and María E. Diaz-Vega
Appl. Sci. 2024, 14(16), 7113; https://doi.org/10.3390/app14167113 - 13 Aug 2024
Cited by 1 | Viewed by 2546
Abstract
Prior research has demonstrated that incorporating solid waste from various sources, such as plastics, civil engineering waste, and industrial and mining waste, into pavement and civil works mixes has notable environmental benefits. This includes reducing the over-exploitation of aggregate banks and preventing waste [...] Read more.
Prior research has demonstrated that incorporating solid waste from various sources, such as plastics, civil engineering waste, and industrial and mining waste, into pavement and civil works mixes has notable environmental benefits. This includes reducing the over-exploitation of aggregate banks and preventing waste materials from being deposited in open-pit landfills for extended periods. This review focuses on sustainable aggregates produced from solid waste with rheological or mechanical properties suitable for replacing conventional aggregates in asphalt or hydraulic concrete mixtures. The aim is to determine the optimal replacement percentage in the mixture to directly impact pavement performance. This review also delves into the impact on fatigue resistance and permanent deformation based on the type of waste material used in construction. Additionally, using sustainable aggregates presents added benefits for pavement binders, such as inhibiting reflection cracks, reducing traffic noise, and prolonging the service life of the pavement. However, it is crucial to study the percentage of replacement of sustainable aggregates in conjunction with other materials using mathematical models and simulations to ensure a substantial contribution to the sustainability of the construction industry. Full article
(This article belongs to the Special Issue Recent Advances in Asphalt Materials and Their Applications)
Show Figures

Figure 1

Back to TopTop