Article
Engineering, Civil
Majid Touqan, M. Hesham El Naggar, Timothy D. Stark
Summary: This paper assesses the performance of a class I railroad superstructure due to track fouling. The results indicate that as the track fouling increases, the range of influence of wheels on the superstructure also increases.
TRANSPORTATION GEOTECHNICS
(2022)
Article
Engineering, Civil
Thanh T. Nguyen, Buddhima Indraratna
Summary: The contamination of ballast by mud pumping leads to reduced shear resistance and increased settlement of railroad foundations. However, the impact of varying water content on the deterioration of fouled ballast has not been well understood. This study found that near the liquid limit of fine soil, there is a critical threshold of water content that causes a significant increase in ballast settlement.
TRANSPORTATION GEOTECHNICS
(2023)
Article
Engineering, Civil
Takahiro Kageyama, Takahisa Nakamura, Ippei Kijiya, Yoshitsugu Momoya, Hirokazu Akagi, Ryuji Saito
Summary: In ballasted tracks on railways, the increase in fine fraction content mixed in ballast leads to higher settlement of the track and increased maintenance frequency. This study presents a new repair method using super-quick hardening cement and polymeric stabilizer to reduce sleeper settlement. The method weakly stabilizes fouled ballast to allow for tamping, reducing the need for costly ballast replacement.
TRANSPORTATION GEOTECHNICS
(2022)
Article
Engineering, Civil
Olivier Chupin, Jean-Michel Piau, Antoine Martin, Christophe Dano, Pierre-Yves Hicher
Summary: This paper demonstrates that the reversible behavior of track ballast under moving train loads can be reasonably modeled using DEM simulations and triaxial tests, with a focus on the effect of a soft support layer and subbase stiffness. The transfer of mechanical loads through force chains in the granular medium and the dependence of homogenized behavior on the sublayer are highlighted. Future research may aim at developing more accurate constitutive models incorporating nonlinear and/or anisotropic aspects based on realistic DEM simulations.
TRANSPORTATION GEOTECHNICS
(2021)
Article
Engineering, Chemical
Mathias Tolomeo, Glenn R. McDowell
Summary: In the Discrete Element modelling of soils, realistic description of the contact response is crucial for investigating small strain ranges. Recent experimental tests show that classic contact models fail to reproduce certain mechanical features, especially when roughness is significant. This study implements these experimental observations in a DEM model and highlights their influence on small strain stiffness.
Article
Engineering, Civil
Juha Latvala, Pauli Kolisoja, Heikki Luomala
Summary: Water content is an important factor influencing the performance of earth structures. Research has shown that the resistance to cyclic loading decreases with an increase in saturation level for sand materials, with the weakest material having a uniform grain size distribution and small median grain size. Fine-grained sand can withstand train loads well when the sub-ballast layer is not completely saturated, but heavy freight traffic may approach the bearing capacity of weak sub-ballast materials if the water content in the upper part of the layer is high. The top part of the sub-ballast layer should be kept below 60-70% saturation level to prevent excessive permanent deformation.
TRANSPORTATION GEOTECHNICS
(2022)
Review
Construction & Building Technology
Vahid Najafi Moghaddam Gilani, Mohammad Habibzadeh, Seyed Mohsen Hosseinian, Reza Salehfard
Summary: Improving railway performance relies on enhancing efficiency and train speed, which can be achieved by improving railway infrastructure. Researchers seek to modify ballast materials, sleepers, and rails, as well as study different geometric and environmental conditions to mitigate existing weaknesses. To evaluate these conditions, various tests must be conducted on railways. While some tests can be performed on-site during train passage, they are limited and pose safety risks. Hence, many tests are conducted using laboratory-scale apparatuses. This study compares different apparatuses used by researchers to simulate railway loading and identifies the most suitable apparatuses for simulating vertical, longitudinal, and lateral loads, as well as measuring noise and vibration.
ADVANCES IN CIVIL ENGINEERING
(2022)
Article
Chemistry, Physical
Cezary Kraskiewicz, Artur Zbiciak, Kacper Wasilewski, Anna Al Sabouni-Zawadzka
Summary: This study focuses on the analysis of under ballast mats in ballasted track structures, and a new mechanical model was developed. The comparison of two testing procedures revealed major discrepancies in the determined values of static and dynamic characteristics, especially for mats with higher stiffness.
Article
Construction & Building Technology
Yujie Qi, Buddhima Indraratna
Summary: Heavier and faster trains have led researchers to explore better ways to absorb the increasing energy and reduce track deterioration. Rubber products are gaining attention for their high damping and energy absorbing capacity. This study evaluates the performance of a rail track with a synthetic energy absorbing layer (SEAL) made of rubber and mining waste. The amount of rubber in the SEAL affects the track's dynamic behavior, with higher amounts leading to increased deformation, energy absorption, damping ratio, and reduced track degradation and lateral movement. The optimal amount of rubber is found to be 10% by mass.
JOURNAL OF MATERIALS IN CIVIL ENGINEERING
(2022)
Article
Engineering, Civil
Shihao Huang, Yu Qian
Summary: Crushed aggregates with irregular shapes and sharp corners are preferred ballast materials due to good particle contact, but they are prone to breakage. This study investigates ballast particle breakage at different stages and finds that corner breakage mainly occurs during compaction rather than shearing. It is recommended to use a rubber pad to reduce ballast breakage during sample compaction in triaxial tests.
TRANSPORTATION RESEARCH RECORD
(2023)
Article
Engineering, Civil
Syed Khaja Karimullah Hussaini, Kumari Sweta
Summary: The study revealed the significant influence of loading frequency on the deformation and degradation behavior of ballast, with geogrids playing a stabilizing role by reducing lateral spreading, vertical settlement, and particle breakage. The relationship between deformations, interface efficiency factor, and geogrid efficiency factor was established, highlighting the importance of geogrids in maintaining ballast integrity under cyclic loading conditions.
PROCEEDINGS OF THE INSTITUTION OF MECHANICAL ENGINEERS PART F-JOURNAL OF RAIL AND RAPID TRANSIT
(2021)
Proceedings Paper
Engineering, Civil
Guilherme Castro, Jose Pires, Rosangela Motta, Robson Costa, Edson Moura, Liedi Bernucci, Luciano Oliveira
Summary: This paper evaluates the unsaturated hydraulic response of a railroad track in Brazil under tropical climate conditions. The analysis shows that the hydraulic behavior of the track is influenced by the presence of fouled ballast, which reduces water transfer and has different hydraulic characteristics in wet and dry seasons.
ADVANCES IN TRANSPORTATION GEOTECHNICS IV, VOL 3
(2022)
Article
Engineering, Geological
Maelckson Bruno Barros Gomes, Antonio Carlos Rodrigues Guimaraes, Filipe Almeida Correa do Nascimento, Juliana Tanabe Assad dos Santos
Summary: There are differences in technical standards for railway ballast published by different countries, associations, and institutions. Various techniques for acquisition, image analysis, and particle scanning have been developed, both in 2D and 3D. This research evaluates the evolution of particle shape parameters and the level of steel slag degradation under stress conditions similar to those experienced in freight transport railways through laboratory tests.
Article
Construction & Building Technology
Pedro Marcelino, Maria de Lurdes Antunes, Eduardo Fortunato, Marta Castilho Gomes
Summary: This paper proposes a general machine learning approach for the development of pavement performance prediction models in pavement management systems, supporting different machine learning algorithms and emphasizing generalization performance.
INTERNATIONAL JOURNAL OF PAVEMENT ENGINEERING
(2021)
Article
Engineering, Geological
Bruno Guimaraes Delgado, Antonio Viana da Fonseca, Eduardo Fortunato, Laura Maria Goretti da Motta
Summary: This paper presents a study on the influence of particle morphology on the mechanical behavior of ballast in railway construction. The results show that steel slag aggregate, with its higher particle angularity, exhibits superior performance compared to traditional granite aggregate.
ENVIRONMENTAL GEOTECHNICS
(2022)
Article
Engineering, Civil
Bruno Guimaraes Delgado, Antonio Viana da Fonseca, Eduardo Fortunato, Paulo Maia
TRANSPORTATION GEOTECHNICS
(2019)
Article
Engineering, Civil
Patricia Jeronimo, Ricardo Resende, Eduardo Fortunato
TRANSPORTATION GEOTECHNICS
(2020)
Article
Computer Science, Interdisciplinary Applications
J. N. Varandas, A. Paixao, E. Fortunato, B. Zuada Coelho, P. Hoelscher
COMPUTERS AND GEOTECHNICS
(2020)
Article
Construction & Building Technology
Andre Paixao, Eduardo Fortunato
Summary: Electric Arc Furnace steel slag aggregate has potential for wider application in railway infrastructures, but its use in ballast layers is often restricted. Research findings show that slag particles have higher angularity and surface texture indices, making them suitable as alternative ballast material.
CONSTRUCTION AND BUILDING MATERIALS
(2021)
Article
Construction & Building Technology
Bruno Guimaraes Delgado, Antonio Viana da Fonseca, Eduardo Fortunato, Andre Paixao, Rubens Alves
Summary: Experimental and numerical comparisons were made between granite aggregate and electrical arc furnace steel slag aggregate for railway ballast, showing that the steel slag aggregate demonstrated superior performance and has the potential to be an ideal alternative material for ballast.
CONSTRUCTION AND BUILDING MATERIALS
(2021)
Article
Engineering, Civil
Eduardo Fortunato, Andre Paixao, Paulo Morais, Carlos Santos, Joao Morais, Jorge Cruz, Nuno Cruz
Summary: The research focuses on reinforcing the subgrade of old railway tracks by injecting grouts into short soil-binder columns formed by drilling through the ballast layer. The study shows a reduction of about 60-80% in settlement amplitudes of the reinforced physical models under cyclic loading, and a general reduction of about 15-20% in peak vertical accelerations measured on the sleepers after treatment, suggesting the proposed reinforcement method is a valid alternative for rehabilitating railway platforms, notably in old single-track lines.
TRANSPORTATION GEOTECHNICS
(2021)
Article
Engineering, Civil
Joao Morais, Paulo Morais, Carlos Santos, Andre Paixao, Eduardo Fortunato
Summary: This paper presents a novel methodology for evaluating the support conditions of railway tracks through modal analysis and observing characteristic frequencies. It demonstrates that this methodology can provide relevant information regarding the railway infrastructure.
PROCEEDINGS OF THE INSTITUTION OF MECHANICAL ENGINEERS PART F-JOURNAL OF RAIL AND RAPID TRANSIT
(2022)
Article
Engineering, Geological
Andre Paixao, Jose Muralha, Ricardo Resende, Eduardo Fortunato
Summary: Photogrammetry-based methods have become an important alternative for measuring the roughness of rock joints. By properly evaluating various aspects, comparable results to traditional methods can be achieved. Comparisons between 3D models generated with different settings and a reference model showed comparable accuracy and roughness parameters. Additionally, this method is more accessible, user-friendly, faster to implement, and less expensive than most current equipment and approaches.
ROCK MECHANICS AND ROCK ENGINEERING
(2022)
Article
Multidisciplinary Sciences
Mafalda Lopes Laranjo, Manuel Matos Fernandes
Summary: Undrained shear strength is a key factor in the behavior of clays, especially in overconsolidated clays. This study focuses on the physical and mechanical properties of Miocene clays, specifically the Prazeres Clay formation in Lisbon. By analyzing a large database of test results, the study establishes a useful framework for geotechnical designers and proposes a range of variation for the undrained shear strength of Prazeres Clay.
SN APPLIED SCIENCES
(2022)
Article
Engineering, Civil
G. Castro, J. Pires, R. Motta, L. Bernucci, E. Fortunato, M. Futai
Summary: This study evaluates the effects of Brazilian southeastern tropical climate on subgrade hydraulic and structural behavior, as well as its effect on the railroad track substructure. It shows that both groundwater level and climate are crucial for evaluating the subgrade structural behavior, track design, and maintenance work. The results indicate that bituminous sub-ballast is more efficient than granular sub-ballast in terms of service life-cycle predictions.
TRANSPORTATION GEOTECHNICS
(2022)
Article
Green & Sustainable Science & Technology
Rubens Alves, Sara Rios, Eduardo Fortunato, Antonio Viana da Fonseca, Bruno Guimaraes Delgado
Summary: The slags and rubber from end-of-life tires pose challenges to the steel and tire industry due to economic and environmental issues. However, these industrial by-products have potential as substitutes for natural raw materials in transportation infrastructures, provided that the mechanical performance meets the required specifications.
Review
Engineering, Geological
Nelson Gomes Mica, Sara Rios, Antonio Viana da Fonseca, Eduardo Fortunato
Summary: The increasing demand for transport infrastructure development requires economically and environmentally viable alternatives to natural aggregates. Industrial by-products can effectively replace these materials, avoiding environmental impacts and providing a destination for the by-products. This study focuses on analyzing the chemical composition, physical and mechanical characteristics, swelling behavior, and leachate content of steelmaking slags for their suitability in the granular layers of transport infrastructures.
GEOTECHNICAL TESTING JOURNAL
(2023)
Article
Construction & Building Technology
Andre Paixao, Jose Nuno Varandas, Eduardo Fortunato
Summary: This study presents a three-dimensional finite element method to simulate the long-term behavior of railway tracks at transition zones, considering the plastic deformation of the ballast layer and the non-linearity of the dynamic vehicle-track interaction. By analyzing the behavior of transition zones in depth, it sheds light on the complex long-term response of these structures and their interdependency with the transient response of the train-track interaction.
FRONTIERS IN BUILT ENVIRONMENT
(2021)
