Featured Research

from universities, journals, and other organizations

Steel-fiber reinforced concrete for conventional construction work as well

Date:
April 2, 2014
Source:
Elhuyar Fundazioa
Summary:
When adding steel fibers the size of a clip, concrete is less prone to cracking, an engineer demonstrates. What the study shows is that this material has certain advantages over conventional reinforced concrete, and it can be used for purposes like the manufacture of cylindrical holding tanks.

Three-dimensional expression of the distribution of the steel fibers.
Credit: Image courtesy of Elhuyar Fundazioa

Reinforcing concrete with steel bars is a very common practice in construction. The industrial engineer and researcher Aimar Orbe-Mateo (UPV/EHU-University of the Basque Country) has studied the possible use of a material that is normally used for other applications for these tasks: concrete reinforced with steel fibers. What the study shows is that this material has certain advantages over conventional reinforced concrete; among others, it is less prone to cracking, and it can be used for purposes like the manufacture of cylindrical holding tanks.

According to Aimar Orbe-Mateo, an engineer at the Faculty of Engineering in Bilbao, right from the start of the study it was clear that "it had to be something that had a practical application, not just any piece of research." Sothe team produced a material for research purposes and which had the potential for being used in construction: steel fiber reinforced self-compacting concrete (SFRSCC).

These are materials that are already being used in building but "they have other applications. Self-compacting concrete, for example, is used in prefabricated buildings. If this concrete is used in conventional building tasks, it is difficult to measure it out because it is very fluid, very runny. Yet its texture allows one to do away with the procedures that are used with conventional concrete (vibration, shovelling, etc.), because it moves and becomes compact on its own," pointed out Orbe.

Steel fibers are also used to reinforce glass, "but more than anything else, to manufacture secondary elements: paving of industrial estates, tunnels, sewage pipelines and such things," he added. These fibers are small, both in terms of length (50 mm) and diameter (1mm), with dimensions similar to those of an unbent paper clip."

From the lab to reality

Alongside the laboratory tests, the team also tested the use to which the material could in fact be put.For this purpose, a wall three metres high and six metres long was built and divided into 380 samples on which various tests were carried out, destructive as well as non-destructive ones, "to determine the structural capabilities of the steel fibers and, in general, the toughness of the wall," highlighted Orbe.

Since the toughness of the structure depends on the orientation and distribution of the fibers within the concrete (impossible to see with the naked eye), the research team resorted to a magnetic system.Firstly, a magnetic field was created inside the samples; then the changes that had taken place in the field were analysed.Two aspects were clarified: the axis towards which the fibers tended to orientate themselves, and how much fiber there was in each sample.According to this study, "the fibers orientated themselves in the direction we were interested in, thanks to the fluid nature of the self-compacting concrete," pointed out the researcher.Apart from these tests, the team carried out computer simulations on fluid dynamics."These simulations showed us that the orientation that the fibers are going to take can be predicted.That way we can detect the weak points and unsuitable concreting processes in advance," pointed out the researcher.

Other tests in the research showed that when compared with conventional concrete reinforcing barsthe steel fibers canmore effectivelycontrol the cracks that may open up when the concrete dries. "There are thousands of fibers distributed throughout the mortar that compact it continually," asserted the engineer.

Orbe believes that with these pieces of research, the material "has reached a level of maturity" and that it can contribute towards making certain construction work easier.Specifically, he is proposing that it be used for manufacturing cylindrical holding tanks for collecting water.Bearing in mind the capacity of the SFRSCC to control cracks better and the results of other studies undertaken by this research team,"the conclusion is thatit is more economical and more sustainable than the conventional structural design," asserted Orbe.

But using it (for the purposes put forward by the research team and for other ones) requires "building contractors to be aware of the advantages of this material." And it is difficult to persuade building contractors not to fit the traditional steel rods, that everything needs to have been mixed into the concrete, because that way it reinforces the, etc.At the same time, one reason for mistrust is the fact that when the concrete dries, it is not possible to see where the fibers are, whether they have been properly distributed or are facing in the right direction. Besides, stresses Orbe, "there are few examples of building work carried out using this system."


Story Source:

The above story is based on materials provided by Elhuyar Fundazioa. Note: Materials may be edited for content and length.


Journal Reference:

  1. A. Orbe, E. Rojν, R. Losada, J. Cuadrado. Calibration patterns for predicting residual strengths of steel fibre reinforced concrete (SFRC). Composites Part B: Engineering, 2014; 58: 408 DOI: 10.1016/j.compositesb.2013.10.086

Cite This Page:

Elhuyar Fundazioa. "Steel-fiber reinforced concrete for conventional construction work as well." ScienceDaily. ScienceDaily, 2 April 2014. <www.sciencedaily.com/releases/2014/04/140402095440.htm>.
Elhuyar Fundazioa. (2014, April 2). Steel-fiber reinforced concrete for conventional construction work as well. ScienceDaily. Retrieved October 21, 2014 from www.sciencedaily.com/releases/2014/04/140402095440.htm
Elhuyar Fundazioa. "Steel-fiber reinforced concrete for conventional construction work as well." ScienceDaily. www.sciencedaily.com/releases/2014/04/140402095440.htm (accessed October 21, 2014).

Share This



More Matter & Energy News

Tuesday, October 21, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Thanks, Marty McFly! Hoverboards Could Be Coming In 2015

Thanks, Marty McFly! Hoverboards Could Be Coming In 2015

Newsy (Oct. 21, 2014) — If you've ever watched "Back to the Future Part II" and wanted to get your hands on a hoverboard, well, you might soon be in luck. Video provided by Newsy
Powered by NewsLook.com
Robots to Fly Planes Where Humans Can't

Robots to Fly Planes Where Humans Can't

Reuters - Innovations Video Online (Oct. 21, 2014) — Researchers in South Korea are developing a robotic pilot that could potentially replace humans in the cockpit. Unlike drones and autopilot programs which are configured for specific aircraft, the robots' humanoid design will allow it to fly any type of plane with no additional sensors. Ben Gruber reports. Video provided by Reuters
Powered by NewsLook.com
Graphene Paint Offers Rust-Free Future

Graphene Paint Offers Rust-Free Future

Reuters - Innovations Video Online (Oct. 21, 2014) — British scientists have developed a prototype graphene paint that can make coatings which are resistant to liquids, gases, and chemicals. The team says the paint could have a variety of uses, from stopping ships rusting to keeping food fresher for longer. Jim Drury reports. Video provided by Reuters
Powered by NewsLook.com
Portable Breathalyzer Gets You Home Safely

Portable Breathalyzer Gets You Home Safely

Buzz60 (Oct. 21, 2014) — Breeze, a portable breathalyzer, gets you home safely by instantly showing your blood alcohol content, and with one tap, lets you call an Uber, a cab or a friend from your contact list to pick you up. Sean Dowling (@SeanDowlingTV) has the details. Video provided by Buzz60
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
 
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:  

Breaking News:

Strange & Offbeat Stories

 

Space & Time

Matter & Energy

Computers & Math

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

Technology News



Save/Print:
Share:  

Free Subscriptions


Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

Get Social & Mobile


Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

Have Feedback?


Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
Mobile iPhone Android Web
Follow Facebook Twitter Google+
Subscribe RSS Feeds Email Newsletters
Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins