The university's Kyle Riding, assistant professor of civil engineering, is leading a three-year study that looks at the freeze-thaw durability of concrete railroad ties. The research is essential to developing safe and durable high-speed rail systems.
Riding is collaborating with Mohammed Albahttiti, civil engineering doctoral candidate from the United Arab Emirates; the university's Institute of Environmental Research; as well as a colleague at the University of Illinois at Urbana-Champaign, and commercial partners Canadian National Railroad and CXT Concrete Ties Inc. The Federal Railroad Association recently awarded Riding more than $1.2 million to study the materials and fabrication process, and to develop quality control tests that ensure safe freeze-thaw durable concrete railroad ties.
"Freeze-thaw is a stressor that happens in pretty much all concrete when it is exposed to water and then freezing and thawing temperatures," Riding said.
When water freezes it grows in size by roughly 9 percent, Riding said. These increases, coupled with the decreases when the ice melts, cause stress on the container the ice forms in. When too much stress occurs the container can break -- similar to what happens when a full soda bottle is left in the freezer.
In concrete rail ties water collects and freezes in the pores of the concrete. As the liquid freezes it creates stress in the railroad tie, which can crack the ties. High-speed rail systems are more sensitive to these problems because of the high speed at which the trains travel on the tracks.
As high-speed rail systems become more widely adopted around the world, it becomes essential to keep passengers safe and maintain the rail system infrastructure against freezing and thawing conditions, Riding said.
To study the freeze-thaw conditions in concrete rail ties, researchers will add surfactants to the concrete as it is being mixed in the laboratory. These compounds produce millions of microscopic bubbles in the concrete that act as pressure release valves to help protect the concrete against damage.
One of the challenges will be to ensure that the bubbles are evenly dispersed through the concrete rail ties and small enough to protect the concrete from damage.
Researchers will evaluate the vibration conditions and air voids created by the bubbles in rail ties produced from various other materials, including surrogate clear materials, cement paste and mortars before scaling up to concrete. The ties will also be studied to determine if they get wet enough on the tracks to cause damage.
Additionally, the team is developing evaluation methods that will help railroad tie manufacturers determine the freeze-thaw resistance of concrete rail ties once they are produced.
"This is a good way to take fundamental science and apply it to a real-world application that will affect our transportation infrastructure and our communities," Riding said. "Plus, who doesn't like trains?"
Kyle Riding, 785-532-1578, firstname.lastname@example.org
Kyle Riding | Newswise Science News
Tool helps cities to plan electric bus routes, and calculate the benefits
09.01.2017 | International Institute for Applied Systems Analysis (IIASA)
Realistic training for extreme flight conditions
28.12.2016 | Technical University of Munich (TUM)
The nearby, giant radio galaxy M87 hosts a supermassive black hole (BH) and is well-known for its bright jet dominating the spectrum over ten orders of magnitude in frequency. Due to its proximity, jet prominence, and the large black hole mass, M87 is the best laboratory for investigating the formation, acceleration, and collimation of relativistic jets. A research team led by Silke Britzen from the Max Planck Institute for Radio Astronomy in Bonn, Germany, has found strong indication for turbulent processes connecting the accretion disk and the jet of that galaxy providing insights into the longstanding problem of the origin of astrophysical jets.
Supermassive black holes form some of the most enigmatic phenomena in astrophysics. Their enormous energy output is supposed to be generated by the...
The probability to find a certain number of photons inside a laser pulse usually corresponds to a classical distribution of independent events, the so-called...
Microprocessors based on atomically thin materials hold the promise of the evolution of traditional processors as well as new applications in the field of flexible electronics. Now, a TU Wien research team led by Thomas Müller has made a breakthrough in this field as part of an ongoing research project.
Two-dimensional materials, or 2D materials for short, are extremely versatile, although – or often more precisely because – they are made up of just one or a...
Two researchers at Heidelberg University have developed a model system that enables a better understanding of the processes in a quantum-physical experiment...
Glaciers might seem rather inhospitable environments. However, they are home to a diverse and vibrant microbial community. It’s becoming increasingly clear that they play a bigger role in the carbon cycle than previously thought.
A new study, now published in the journal Nature Geoscience, shows how microbial communities in melting glaciers contribute to the Earth’s carbon cycle, a...
20.04.2017 | Event News
18.04.2017 | Event News
03.04.2017 | Event News
21.04.2017 | Physics and Astronomy
21.04.2017 | Health and Medicine
21.04.2017 | Physics and Astronomy