Article
Green & Sustainable Science & Technology
Xunhao Ding, Punyaslok Rath, Oliver Giraldo-Londono, William G. Buttlar, Tao Ma
Summary: This study investigates the effects of rubber on anti-crack resistance for binders at low temperatures using the Discrete Element Method. The simulation results show that rubber particles play a significant role in improving the binder's crack resistance, resulting in a ductile failure mode and higher fracture energy.
JOURNAL OF CLEANER PRODUCTION
(2022)
Article
Engineering, Chemical
J. Girardot, J. B. Kopp, B. Croquelois, P. Tchoreloff, S. Morel, V. Mazel
Summary: Pharmaceutical tablets need to have sufficient mechanical strength, which is often evaluated using the diametral compression test. However, this test can lead to unstable failures. By applying load-unload cycles to tablets during the diametral compression test, it was found that the concept of equivalent linear elastic fracture mechanics can be successfully applied to Mode I fracture behavior. This revealed the development of a Fracture Process Zone (FPZ), indicative of a quasi-brittle behavior, and the existence of a second dissipative mechanism caused by friction in the FPZ during cyclic loading.
Article
Microbiology
Sarelia M. Castaneda Alejo, Kevin Tejada Meza, Maria R. Valderrama Valencia, Armando J. Arenazas Rodriguez, Christian J. Malaga Espinoza
Summary: This study explores a bacterial consortium that can degrade rubber tires without any chemical pretreatment. Genetic sequencing analysis reveals that the consortium is mainly composed of Delftia tsuruhatensis, and a degradation point of 4.94% is obtained in the experiment.
Article
Chemistry, Physical
Katarzyna Klajn, Tomasz Gozdek, Dariusz M. Bielinski, Mariusz Sicinski, Magdalena Zarzecka-Napierala, Zbigniew Pedzich
Summary: This study compares three different methods of modifying ground tire rubber (GTR) and their effects on the mechanical properties of vulcanizates. The addition of modified GTR particles results in increased stiffness and crosslink density of the vulcanizates, but also leads to decreased friction and increased abrasive wear.
Article
Polymer Science
Nicolas Candau, Oguzhan Oguz, Noel Leon Albiter, Gero Forster, Maria Lluisa Maspoch
Summary: By using Dicumyl peroxide (DCP) as a crosslinking agent, recycling waste tire rubber (GTR) with poly (lactic acid) (PLA) can improve the toughness and impact strength of the material. Grinding GTR can enhance the performance of the blend, with the finest GTR showing the best improvement in tensile strength, modulus, strain at break, energy at break, and impact strength compared to neat PLA.
Article
Green & Sustainable Science & Technology
XiaoPing Wang, QiMing Luo, ChangYuan Hu
Summary: This paper presents a sustainable strategy for the fabrication of reprocessable elastomer (GTRE) using ground tire rubber (GTR). By mechano-chemically modifying GTR and introducing a dynamic crosslinked network, the mechanical strength of GTRE can be tailored and it can be reprocessed multiple times.
JOURNAL OF CLEANER PRODUCTION
(2022)
Article
Engineering, Mechanical
Changshuai Shi, Ao Wang, Xiaohua Zhu, Feilong Cheng
Summary: The research findings provide theoretical guidance for the structural design and bonding process parameters of SET rubber. The study shows that the friction coefficient for the casing-rubber-SET system should be about 0.15 to ensure a small driving force during the expansion process. Increasing the theoretical compression and length of rubber can effectively improve the suspension force and sealing performance of rubber.
ENGINEERING FAILURE ANALYSIS
(2022)
Article
Chemistry, Physical
Aleksander Hejna, Adam Olszewski, Lukasz Zedler, Paulina Kosmela, Krzysztof Formela
Summary: The study examined the impact of GTR oxidation with hydrogen peroxide and potassium permanganate on the processing and properties of flexible polyurethane/GTR composite foams. Results showed that H2O2 modifications improved mechanical performance, while KMnO4 treatment accelerated the polymerization process.
Article
Polymer Science
Rafael Perez-Campos, Jose Fayos-Fernandez, Juan Monzo-Cabrera, Fernando Martin Salamanca, Juan Lopez Valentin, Jose Manuel Catala-Civera, Pedro Plaza-Gonzalez, Juan Rafael Sanchez-Marin
Summary: Efforts are being made to find innovative ways of recycling rubber from end-of-life tires through devulcanization. This study shows that microwave heating is a controllable and efficient method for devulcanizing the rubber, and the changes in the rubber's permittivity can be used to monitor the process.
Article
Chemistry, Multidisciplinary
Daniel Abel Simon, Tamas Barany
Summary: In this study, we devulcanized ground tire rubber (GTR) using microwaves at different temperatures and heating rates. We evaluated the soluble content and cross-link density of the samples and determined the microwave energy and selectivity parameter during devulcanization. The results showed that lower temperatures and slower heating rates resulted in better devulcanization effects and higher selectivity. However, higher temperatures led to severe degradation despite achieving a higher degree of devulcanization. Additionally, introducing devulcanized GTRs to natural rubber-based mixtures using a two-step mixing method improved the mechanical properties, especially tear strength.
ACS SUSTAINABLE CHEMISTRY & ENGINEERING
(2023)
Article
Chemistry, Multidisciplinary
Antoniya Toncheva, Loic Brison, Philippe Dubois, Fouad Laoutid
Summary: This study incorporated recycled tire rubber into polymer matrices using selective laser sintering as 3D printing technology. The morphological characteristics, mechanical properties, and thermal stability of the polymer composites were evaluated to reveal the potential of using recycled tire rubber in additive manufacturing.
APPLIED SCIENCES-BASEL
(2021)
Article
Mechanics
Shengjia Wu, Jwo Pan, Paul S. Korinko, Michael J. Morgan
Summary: Crack extensions in uncharged and hydrogen-charged side-grooved A(T) specimens of conventionally forged 21-6-9 austenitic stainless steels were simulated using the cohesive zone modeling approach. Finite element analyses with fixed and varying cohesive parameters were conducted to fit the experimental data, with results showing that the average cohesive energy for hydrogen-charged specimens is lower than uncharged specimens.
ENGINEERING FRACTURE MECHANICS
(2021)
Article
Environmental Sciences
Aleksander Hejna, Paulina Kosmela, Adam Olszewski, Lukasz Zedler, Krzysztof Formela, Katarzyna Skorczewska, Adam Piasecki, Mariusz Marc, Roman Barczewski, Mateusz Barczewski
Summary: Rapid economic growth has led to increased waste generation in multiple industries, including the automotive sector, due to the lack of established recycling and utilization methods. One particular concern is the large amount of post-consumer tires, which are considered burdensome waste due to the emission of volatile organic compounds (VOCs). To address this issue, novel and environmentally friendly methods for utilizing these tires are needed. One promising approach is shredding the tires to generate ground tire rubber (GTR), which can be used as filler in polymeric materials. This study focuses on the thermomechanical treatment of GTR with zinc borate in a twin-screw extruder to improve its performance in flexible polyurethane (PU) foams. The impact of modification parameters on various properties, including cellular structure, mechanical performance, thermal stability, thermal insulation, and acoustic properties, was investigated. VOC emissions from the fillers and composites were also monitored and evaluated. The results showed that the proposed method of GTR thermomechanical treatment with zinc borate particles can enhance the performance of flexible PU foamed composites and reduce VOC emissions, thus expanding the application range of GTR and providing new ways for its efficient utilization.
ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH
(2023)
Article
Chemistry, Physical
Paulina Kosmela, Adam Olszewski, Lukasz Zedler, Paulina Burger, Adam Piasecki, Krzysztof Formela, Aleksander Hejna
Summary: The versatile application range of polyurethane foam allows for adjustment of structure and performance. Research is being conducted on developing new raw materials, including those from renewable resources or recycling, to further broaden its potential. Thermo-mechanical modification of ground tire rubber particles with fresh and waste oil has been shown to enhance the thermal and mechanical performance of polyurethane foam composites.
Article
Materials Science, Characterization & Testing
Nicolas Candau, Oguzhan Oguz, Carlos Eloy Federico, Gregory Stoclet, Jean-Francois Tahon, Maria Lluisa Maspoch
Summary: The study on strain induced crystallization (SIC) of peroxide vulcanized natural rubber (NR)/ground tire rubber (GTR) composites showed that incorporating GTR into the NR matrix enhances the reinforcement of the composites at room temperature by acting as reinforcing fillers with high carbon black content, and by nucleating SIC in the NR matrix to generate more oriented crystallites that behave as supplementary reinforcing fillers.
Article
Construction & Building Technology
Hamed Majidifard, Behnam Jahangiri, Punyaslok Rath, Loreto Urra Contreras, William G. Buttlar, Amir H. Alavi
Summary: A new model for predicting the rutting depth of asphalt mixtures using gene expression programming (GEP) technique was developed in this study based on 96 Hamburg test results. The model is capable of accurately capturing the differences in mixture properties and test conditions, and shows great potential for various applications.
CONSTRUCTION AND BUILDING MATERIALS
(2021)
Article
Engineering, Multidisciplinary
Hamed Majidifard, Behnam Jahangiri, Punyaslok Rath, William G. Buttlar
Summary: A new cracking index BCI was introduced in this study, showing lower coefficient of variation and higher correlation compared to existing indices FI and CRI. BCI is driven by both fracture energy and L75 parameter, suggesting potential value in predicting cracking performance of asphaltic pavement surfaces.
Article
Construction & Building Technology
Behnam Jahangiri, Punyaslok Rath, Hamed Majidifard, Loreto Urra, William G. Buttlar
Summary: This study investigates the lab and field performance of four asphalt mixtures containing reclaimed asphalt pavement (RAP) and recycled asphalt shingles (RAS) in Missouri, USA. The mixtures exhibited high cracking potential and brittle behavior, but rutting was not a concern. Statistical analysis and simulations were used to distinguish between mixes and evaluate performance tests, with DC(T) showing the best ability to differentiate between mixtures. Field data collected using ARAN was also analyzed to further assess laboratory performance tests.
ROAD MATERIALS AND PAVEMENT DESIGN
(2022)
Article
Construction & Building Technology
Hamed Majidifard, Behnam Jahangiri, Punyaslok Rath, Amir H. Alavi, William G. Buttlar
Summary: The Hamburg wheel tracking test (HWTT) is a commonly used procedure to simulate rutting phenomena in asphalt mixtures. A new model based on convolution neural network (CNN) was developed using a database of 10,000 data points from HWTT results, which can predict rut depth in asphalt mixtures considering various influencing variables. This model can be used for estimating rut depth in situations where laboratory testing is not feasible or for pre-design trials.
ROAD MATERIALS AND PAVEMENT DESIGN
(2021)
Article
Construction & Building Technology
Punyaslok Rath, Nandita Gettu, Shishi Chen, William G. Buttlar
Summary: Lab studies show that rubber modification of asphalt improves certain properties of asphalt mixtures and can extend service life. However, conflicting results are often seen in modern laboratory cracking tests for rubber-modified asphalt mixtures. A fracture mechanics based test was conducted on unmodified and modified binder systems, revealing that unmodified and polymer-modified specimens failed in a brittle manner, while rubber-modified specimens exhibited increasing ductile-type failures with higher rubber modification levels. Analysis of fractured faces under a Scanning Electron Microscope indicated the presence of characteristic tails and cavities in rubber-modified specimens, suggesting a crack-pinning-type toughening mechanism.
ROAD MATERIALS AND PAVEMENT DESIGN
(2022)
Article
Engineering, Civil
Punyaslok Rath, Hamed Majidifard, Behnam Jahangiri, Shishi Chen, William G. Buttlar
Summary: The study shows that DP-GTR modification can increase high temperature performance grade, rut resistance, and fracture energy at low temperatures in asphalt binders and mixtures, while reducing rut depth, flexibility index, and cracking test index. Field performance of chemically treated DP-GTR sections in different states demonstrated good-to-excellent cracking and rutting resistance, suggesting that some popular cracking tests may not adequately evaluate GTR-modified asphalt mixtures.
TRANSPORTATION RESEARCH RECORD
(2021)
Article
Materials Science, Characterization & Testing
Punyaslok Rath, J. Meister, B. Jahangiri, W. Buttlar
Summary: This study examined the effects of chemically engineered crumb rubber (ECR) modification on dense-grade asphalt mixtures. The findings showed that ECR modification greatly improved resistance to rutting and cracking, leading to longer service life. Additionally, ECR modification can result in cost savings and the ability to pass draindown tests without the need for fibers.
JOURNAL OF TESTING AND EVALUATION
(2022)
Article
Engineering, Civil
Behnam Jahangiri, Punyaslok Rath, Hamed Majidifard, William G. Buttlar
Summary: Various agencies have researched and introduced performance-related specifications (PRS) for asphalt mixtures design, focusing on cracking test development and evaluation. A comprehensive research project at Illinois Tollway led to the establishment of a PRS for mainline and shoulder asphalt mixtures, with the DC(T) test selected for crack-resistant mixtures design and tailored thresholds for rut depth and stripping inflection points.
TRANSPORTATION RESEARCH RECORD
(2021)
Article
Construction & Building Technology
Punyaslok Rath, Loreto Urra Contreras, Behnam Jahangiri, Hamed Majidifard, William G. Buttlar
Summary: This study aims to establish a mixture-based temperature grading system as an alternative to the existing system for recovered binders. A novel Mixture Performance Grading system is proposed using two mixture tests to compute a mixture-based performance grade, showing excellent correlation with field performance data.
CONSTRUCTION AND BUILDING MATERIALS
(2021)
Article
Engineering, Civil
Punyaslok Rath, James Meister, Fabricio Arteaga-Larios, C. J. DuBois, Cristina Serrat, William Buttlar
Summary: Research has shown that waste materials such as scrap tires and plastics can be utilized in the development and modification of asphalt pavements. A field demonstration project conducted in Columbia confirmed the effectiveness of using ground tire rubber and recycled plastics. These methods can reduce the reliance on virgin polymers and chemical treatments in asphalt production.
TRANSPORTATION RESEARCH RECORD
(2022)
Article
Engineering, Civil
Hamed Majidifard, Punyaslok Rath, Behnam Jahangiri, William G. Buttlar
Summary: This study aimed to improve or redesign dense-graded mixtures in Missouri using a balanced mix design approach. The results showed that modification with rubber and softer binder was the most efficient strategy for improving the mixture's performance. Additionally, the use of a softer binder or rejuvenator led to success in meeting specific test requirements while maintaining a balance with other requirements.
TRANSPORTATION RESEARCH RECORD
(2023)
Article
Green & Sustainable Science & Technology
Xunhao Ding, Punyaslok Rath, Oliver Giraldo-Londono, William G. Buttlar, Tao Ma
Summary: This study investigates the effects of rubber on anti-crack resistance for binders at low temperatures using the Discrete Element Method. The simulation results show that rubber particles play a significant role in improving the binder's crack resistance, resulting in a ductile failure mode and higher fracture energy.
JOURNAL OF CLEANER PRODUCTION
(2022)
Proceedings Paper
Construction & Building Technology
Punyaslok Rath, Redmond Clark, Doug Zuberer, William Buttlar
Summary: Ground Tire Rubber (GTR) is increasingly popular as a recycled mixture component and performance-enhancing asphalt mix modifier in multiple U.S. states, driven by advances in production technologies, material specifications, testing methods, cost-saving initiatives, and favorable field performance comparisons. Field data, economic data, and contractor feedback from various states indicate that GTR-modified mixes can perform similarly to polymer-modified mixtures at significantly lower costs.
AIRFIELD AND HIGHWAY PAVEMENTS 2021: PAVEMENT MATERIALS AND SUSTAINABILITY
(2021)
Article
Engineering, Civil
He Wang, Punyaslok Rath, William G. Buttlar
JOURNAL OF TRAFFIC AND TRANSPORTATION ENGINEERING-ENGLISH EDITION
(2020)
