Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Crash safety in rail vehicles

03.03.2008
A group of structural engineers at Vienna University of Technology (TU) are working on simulating the behaviour of weld seams under crash loading.

Particular emphasis is being placed on rail vehicles where, on the one hand, improved crash safety is being demanded and, on the other hand, only a limited number of real crash tests can be performed due to the high costs involved. Simulation models are to allow an improved assessment of the failure of welds in the future.

At present, crash tests represent the state of the art not only in the automobile industry but also in the rail vehicle sector. In the course of a cooperative project with Siemens Transportation Systems TU researchers investigated the strength of weld seams in rail vehicles under crash loading as part of a research project funded by the city of Vienna (ZIT). “During collisions not only individual structural components but also the joints between them are exposed to enormous loads. Spot welds play an important role in the crash behaviour of motor vehicles, whereas rail vehicles tend to employ continuous weld seams. Both can be critical in the event of a collision”, notes Helmut Böhm, Head of the Institute of Lightweight Design and Structural Biomechanics of Vienna University of Technology (TU).

The reason why welded joints may be subject to failure lies in the thermal conditions they are subjected to during welding. The metal is heated and molten, which can significantly modify its properties. With the aid of computer simulations professor Böhm and project assistant Christian Grohs studied the inhomogeneous and heat affected material involved in weld seams. “The objective is to enable the structure to absorb as much kinetic energy as possible during a crash. It is constructed in such a way that it can be severely deformed, e.g. by developing patterns of folds. This reduces the risk of injury for passengers”, says Helmut Böhm. Christian Grohs adds: “An extensive experimental test programme, which forms the basis for numerical analysis, was defined and carried out in cooperation with the Institute of Materials Sciences and Technology. We can then recheck the test results and construct better models using this data. The test structure was defined in such a way that the weld seams are located at the most unfavourable positions with the aim of inducing them to fail during the test. The models, in turn, serve to improve the design of rail vehicles”.

A new standard on the collision safety of rail vehicles is to be introduced in 2008. Since crash tests of rail vehicles are very expensive, simulations play a major role in verifying their crash behaviour. Such work must demonstrate that gross deformations of rail vehicles are restricted to so-called crash zones which are situated in regions where there are no people. Dr. Seitzberger, crash expert at Siemens Transportation Systems, states: “An intensive basic research-oriented debate on the issue of the passive safety must be regarded as essential for successfully carrying out future projects. The present cooperation represents a significant contribution to the continued development of know-how and competence in this field and will contribute to enhancing the safety of modern rail vehicles”.

Daniela Hallegger | alfa
Further information:
http://www.tuwien.ac.at/pr

More articles from Transportation and Logistics:

nachricht Study sets new distance record for medical drone transport
13.09.2017 | Johns Hopkins Medicine

nachricht Researchers 'count cars' -- literally -- to find a better way to control heavy traffic
10.08.2017 | Florida Atlantic University

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: In best circles: First integrated circuit from self-assembled polymer

For the first time, a team of researchers at the Max-Planck Institute (MPI) for Polymer Research in Mainz, Germany, has succeeded in making an integrated circuit (IC) from just a monolayer of a semiconducting polymer via a bottom-up, self-assembly approach.

In the self-assembly process, the semiconducting polymer arranges itself into an ordered monolayer in a transistor. The transistors are binary switches used...

Im Focus: Demonstration of a single molecule piezoelectric effect

Breakthrough provides a new concept of the design of molecular motors, sensors and electricity generators at nanoscale

Researchers from the Institute of Organic Chemistry and Biochemistry of the CAS (IOCB Prague), Institute of Physics of the CAS (IP CAS) and Palacký University...

Im Focus: Hybrid optics bring color imaging using ultrathin metalenses into focus

For photographers and scientists, lenses are lifesavers. They reflect and refract light, making possible the imaging systems that drive discovery through the microscope and preserve history through cameras.

But today's glass-based lenses are bulky and resist miniaturization. Next-generation technologies, such as ultrathin cameras or tiny microscopes, require...

Im Focus: Stem cell divisions in the adult brain seen for the first time

Scientists from the University of Zurich have succeeded for the first time in tracking individual stem cells and their neuronal progeny over months within the intact adult brain. This study sheds light on how new neurons are produced throughout life.

The generation of new nerve cells was once thought to taper off at the end of embryonic development. However, recent research has shown that the adult brain...

Im Focus: Interference as a new method for cooling quantum devices

Theoretical physicists propose to use negative interference to control heat flow in quantum devices. Study published in Physical Review Letters

Quantum computer parts are sensitive and need to be cooled to very low temperatures. Their tiny size makes them particularly susceptible to a temperature...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

2nd International Conference on High Temperature Shape Memory Alloys (HTSMAs)

15.02.2018 | Event News

Aachen DC Grid Summit 2018

13.02.2018 | Event News

How Global Climate Policy Can Learn from the Energy Transition

12.02.2018 | Event News

 
Latest News

Contacting the molecular world through graphene nanoribbons

19.02.2018 | Materials Sciences

When Proteins Shake Hands

19.02.2018 | Materials Sciences

Cells communicate in a dynamic code

19.02.2018 | Life Sciences

VideoLinks
Science & Research
Overview of more VideoLinks >>>