Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:


New ultrasonic technology could help prevent train derailments

Researchers have developed a new technique they said is better able than currently used technology to find defects in steel railroad tracks

Researchers at the University of California, San Diego have developed a new technique they said is better able than currently used technology to find defects in steel railroad tracks, including hard-to-find internal cracks that can break under the weight of passing trains. Track defects account for about one-third of the 2,200 annual train derailments in the U.S., according to the Federal Railroad Administration (FRA), the federal agency charged with enforcing rail safety regulations.

A team led by UCSD structural engineering professor Francesco Lanza di Scalea describes in the Aug. 22 issue of the Journal of Sound and Vibration a defect-detection technique that uses laser beam pulses to gently "tap" on steel rails. Each laser tap sends ultrasonic waves traveling 1,800 miles per second along the steel rails. Downward facing microphones are positioned a few inches above the rail and 12 inches from the downward pointed laser beam. As the prototype vehicle rolls down the test track delivering laser beams taps at one-foot intervals, the microphones detect any telltale reductions in the strength of the ultrasonic signals, pinpointing surface cuts, internal cracks, and other defects.

In March 2006, Lanza di Scalea, project scientist Piervincenzo Rizzo and doctoral students Stefano Coccia and Ivan Bartoli tested a prototype vehicle equipped with the UCSD technology at a test track in Gettysburg, PA. The researchers detected 76.9 to 100 percent of internal defects and 61.5 to 90 percent of surface cuts in dry and wet conditions, respectively.

The UCSD team was supported by ENSCO, Inc., an engineering and technology company headquartered in Falls Church, VA, that develops inspection technologies for the Department of Transportation and other government agencies.

Lanza di Scalea and his team will test an improved design of their technology this fall in Gettysburg as part of an ongoing study funded by the FRA.

"Some of the worst derailments in this country have occurred on tracks recently inspected by the current generation of technology, which often doesn't detect interior cracks in rails that happen to lie under areas of superficial cracking," said Lanza di Scalea. "Our technique is much better able to find such defects, and it can work under varying weather conditions while the inspection vehicle is zipping along a track at speeds of up to 70 mph."

Rail carriers moved 42 percent of America's total coal, chemicals, minerals, food and other goods shipped in 2005, according to the U.S. Department of Transportation. Track-related damage from derailments and other incidents doubled from $55 million in 1993 to $111 million in 2000, and the trend toward longer trains pulling heavier cars at higher speeds creates the potential for even greater losses.

The current generation of track-inspection technologies relies on a variety of techniques, including water-filled wheels or sleds that move over track surfaces at roughly 30 mph while sending ultrasonic pulses downward into the track. The inaudible ultrasonic pulses reflect back as echoes when they encounter cracks. Unfortunately, the signals are routinely blocked by superficial surface cracks from detecting more dangerous internal cracks.

Surface cracking does not interfere with the movement of ultrasonic pulses in the UCSD technology. "The ultrasonic sound we use doesn't come from the top of the rail, but instead travels along the rail," said Lanza di Scalea. "Our pulsed-laser technique, combined with ultrasonic microphones positioned a few inches above the rails and sophisticated software that filters out noise and other sources of variability is potentially very effective at finding internal rail defects."

Rex Graham | EurekAlert!
Further information:

More articles from Transportation and Logistics:

nachricht Bremen University students reach the final at robotics competition with parcel delivery robot
19.10.2016 | BIBA - Bremer Institut für Produktion und Logistik

nachricht Discovering electric mobility in a playful way
18.08.2016 | Fraunhofer-Institut für Arbeitswirtschaft und Organisation IAO

All articles from Transportation and Logistics >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Light-driven atomic rotations excite magnetic waves

Terahertz excitation of selected crystal vibrations leads to an effective magnetic field that drives coherent spin motion

Controlling functional properties by light is one of the grand goals in modern condensed matter physics and materials science. A new study now demonstrates how...

Im Focus: New 3-D wiring technique brings scalable quantum computers closer to reality

Researchers from the Institute for Quantum Computing (IQC) at the University of Waterloo led the development of a new extensible wiring technique capable of controlling superconducting quantum bits, representing a significant step towards to the realization of a scalable quantum computer.

"The quantum socket is a wiring method that uses three-dimensional wires based on spring-loaded pins to address individual qubits," said Jeremy Béjanin, a PhD...

Im Focus: Scientists develop a semiconductor nanocomposite material that moves in response to light

In a paper in Scientific Reports, a research team at Worcester Polytechnic Institute describes a novel light-activated phenomenon that could become the basis for applications as diverse as microscopic robotic grippers and more efficient solar cells.

A research team at Worcester Polytechnic Institute (WPI) has developed a revolutionary, light-activated semiconductor nanocomposite material that can be used...

Im Focus: Diamonds aren't forever: Sandia, Harvard team create first quantum computer bridge

By forcefully embedding two silicon atoms in a diamond matrix, Sandia researchers have demonstrated for the first time on a single chip all the components needed to create a quantum bridge to link quantum computers together.

"People have already built small quantum computers," says Sandia researcher Ryan Camacho. "Maybe the first useful one won't be a single giant quantum computer...

Im Focus: New Products - Highlights of COMPAMED 2016

COMPAMED has become the leading international marketplace for suppliers of medical manufacturing. The trade fair, which takes place every November and is co-located to MEDICA in Dusseldorf, has been steadily growing over the past years and shows that medical technology remains a rapidly growing market.

In 2016, the joint pavilion by the IVAM Microtechnology Network, the Product Market “High-tech for Medical Devices”, will be located in Hall 8a again and will...

All Focus news of the innovation-report >>>



Event News

#IC2S2: When Social Science meets Computer Science - GESIS will host the IC2S2 conference 2017

14.10.2016 | Event News

Agricultural Trade Developments and Potentials in Central Asia and the South Caucasus

14.10.2016 | Event News

World Health Summit – Day Three: A Call to Action

12.10.2016 | Event News

Latest News

Oasis of life in the ice-covered central Arctic

24.10.2016 | Earth Sciences

‘Farming’ bacteria to boost growth in the oceans

24.10.2016 | Life Sciences

Light-driven atomic rotations excite magnetic waves

24.10.2016 | Physics and Astronomy

More VideoLinks >>>