scholarly journals Failure investigations into interspersed railway tracks exposed to flood and washaway conditions under moving train loads

Author(s):  
Mohamad Ali Ridho B K A ◽  
Sakdirat Kaewunruen
Keyword(s):  
2008 ◽  
Vol 30 (2) ◽  
pp. 32-36 ◽  
Author(s):  
Christine Kovic

July 2007. Hundreds of Central American migrants were camped along the railway tracks in Arriaga, Chiapas waiting to for the freight train to leave. Some were eating, perhaps their last food for days, others had bottles of water tied across their shoulders, some attempted to rest under the train cars to escape the hot sun. One young man brushed his teeth under the trees, using the water he carried in a recycled coca-cola bottle, to prepare himself for the journey ahead. Arriaga, a town of 25,000 people, is split in half by the train tracks. The town's tiny plaza, with a small playground, fondas (eateries), and a railway museum, sits on one side of the tracks. The town's church and market lie on the other. These Central American migrants in Arriaga, some 150 miles from Mexico's southern border with Guatemala, were eager to jump the freight train to continue their journey north to the United States. The train had not left Arriaga for a full week and many were desperate as they felt trapped. Their preparations underscored the dangers and harshness of the trip. They would have to hold on to the train for hours and days at a time, riding on ladders and the roofs of tank cars. Those who fall asleep and lose their grip risk death or severe injury, such as dismemberment.


2018 ◽  
Vol 18 (01) ◽  
pp. 1850011 ◽  
Author(s):  
Sakdirat Kaewunruen ◽  
Tomasz Lewandrowski ◽  
Kritditorn Chamniprasart

This paper investigates novel dynamic phenomena of interspersed railway tracks. The interspersed method is commonly carried out by spot-replacing old timber sleepers with new concrete sleepers. Although this interspersed approach provides a short-term solution, such method has a negative effect on the long-term performance of railway tracks. It is evident that the performance of interspersed tracks can quickly deteriorate after some years. As a result, this paper is the first to evaluate dynamic responses of the interspersed track caused by a moving train load in order to understand the root cause of swift track deterioration. Interspersed track models in three-dimensional space have been developed using a finite element package, STRAND7. The model was validated earlier with experimental results. Parametric studies have been conducted to evaluate dynamic responses of the interspersed railway tracks, including dynamic displacement, frontal uplift, rear uplift and accelerations of rail over sleeper, rail at midspan, sleeper at rail seat, and sleeper at midspan. Dynamic amplification phenomena are highlighted as they convey a new insight into dynamic phenomena identifying the real source of track deterioration.


Author(s):  
Seyed-Ali Mosayebi ◽  
Jabbar Ali Zakeri ◽  
Morteza Esmaeili

The support condition of railway sleepers has a significant effect on the mechanical behavior of railway tracks due to the passing of different trains. One of the important issues in this regard relates to existing unsupported sleepers on the railway tracks. These sleepers cause changes in the dynamic responses of railway tracks under a moving train. In the literature, the effects of train bogie patterns on the behavior of tracks with and without unsupported sleepers have not been completely investigated till now. Therefore, the present study investigates this issue using numerical analyses. In this regard, first, a finite element model of a railway track is utilized, and the results are verified and validated against those of previous studies. Then, equations of three vehicle models are derived and their interactions with the track model are investigated. These models include vehicles without bogies and vehicles with two- and three-axle bogies. During the numerical analyses, the effects of the unsupported sleepers on the dynamic performance of the track are studied. Finally, based on the achieved numerical results, many regression equations are derived between the train axle loads with rail bending moments, sleeper displacements, and support forces for tracks.


Author(s):  
Simin Zou ◽  
Xuhui He

The unprecedented COVID-19 pandemic has caused a traffic tie-up across the world. In addition to home quarantine orders and travel bans, the social distance guideline of about six feet was enacted to reduce the risk of contagion. However, with recent life gradually returning to normal, the crisis is not over. In this research, a moving train test and a Gaussian puff model were employed to investigate the impact of wind raised by a train running on the transmission and dispersion of SARS-CoV-2 from infected individuals. Our findings suggest that the 2 m social distance guideline may not be enough; under train-induced wind action, human respiratory disease-carrier droplets may travel to unexpected places. However, there are deficiencies in passenger safety guidelines and it is necessary to improve the quantitative research in the relationship between train-induced wind and virus transmission. All these findings could provide a fresh insight to contain the spread of COVID-19 and provide a basis for preventing and controlling the pandemic virus, and probe into strategies for control of the disease in the future.


Materials ◽  
2020 ◽  
Vol 14 (1) ◽  
pp. 169
Author(s):  
Kazem Jadidi ◽  
Morteza Esmaeili ◽  
Mehdi Kalantari ◽  
Mehdi Khalili ◽  
Moses Karakouzian

Asphalt is a common material that is used extensively for roadways. Furthermore, bituminous mixes have been used in railways, both as asphalt and as mortar. Different agencies and research institutes have investigated and suggested various applications. These studies indicate the benefits of bituminous material under railways, such as improving a substructure’s stiffness and bearing capacity; enhancing its dynamic characteristics and response, especially under high-speed train loads; waterproofing the subgrade; protecting the top layers against fine contamination. These potential applications can improve the overall track structure performance and lead to minimizing settlement under heavy loads. They can also guarantee an appropriate response under high-speed loads, especially in comparison to a rigid slab track. This review paper documents the literature related to the utilization of asphalt and bituminous mixes in railway tracks. This paper presents a critical review of the research in the application of asphalt and bituminous mixes in railway tracks. Additionally, this paper reviews the design and construction recommendations and procedures for asphalt and bituminous mixes in railway tracks as practiced in different countries. This paper also provides case studies of projects where asphalt and bituminous mixes have been utilized in railway tracks. It is anticipated that this review paper will facilitate (1) the exchange of ideas and innovations in the area of the design and construction of railway tracks and (2) the development of unified standards for the design and construction of railway tracks with asphalt and bituminous mixtures.


Sign in / Sign up

Export Citation Format

Share Document