Reinforced high-strength concrete can crack due to stresses that develop during the hardening process. However, this has been found to be surprisingly less quick than previously thought. Due to Dutch research, extra steps during the hardening process can be omitted. This will result in cheaper concrete.
Maya Sule from Delft University of Technology tested specimens of high strength concrete (concrete with little water) in a temperature stress testing machine (TSTM). Such tests indicate the progression of the stress development in the concrete specimens. They also predict the moment at which cracks will occur. Freshly poured concrete radiates heat during the hardening process and expands as a result of this. Upon cooling the concrete contracts again. If this so-called temperature contraction is prevented, for example due to the concrete being poured upon an existing foundation, cracks occur. As high strength concrete contains less water than normal concrete, the contraction is further increased due to the mix drying out on the inside.
The researchers assessed the nature of the crack formation by placing test specimens of non-reinforced high-strength concrete under tension. This led to a single through-crack. However, dependent on the reinforcement method used there were also some test specimens with shallow cracks which did not seriously weaken the test specimen. The non-reinforced test specimen with a single through-crack, completely cracked much more quickly than the reinforced test piece. In other words, reinforced high-strength concrete is less sensitive for cracks than non-reinforced high-strength concrete.
Nalinie Moerlie | alfa
Magnesium magnificent for plasmonic applications
23.05.2018 | Rice University
New concept for structural colors
18.05.2018 | Technische Universität Hamburg-Harburg
At the LASYS 2018, from June 5th to 7th, the Laser Zentrum Hannover e.V. (LZH) will be showcasing processes for the laser material processing of tomorrow in hall 4 at stand 4E75. With blown bomb shells the LZH will present first results of a research project on civil security.
At this year's LASYS, the LZH will exhibit light-based processes such as cutting, welding, ablation and structuring as well as additive manufacturing for...
There are videos on the internet that can make one marvel at technology. For example, a smartphone is casually bent around the arm or a thin-film display is rolled in all directions and with almost every diameter. From the user's point of view, this looks fantastic. From a professional point of view, however, the question arises: Is that already possible?
At Display Week 2018, scientists from the Fraunhofer Institute for Applied Polymer Research IAP will be demonstrating today’s technological possibilities and...
So-called quantum many-body scars allow quantum systems to stay out of equilibrium much longer, explaining experiment | Study published in Nature Physics
Recently, researchers from Harvard and MIT succeeded in trapping a record 53 atoms and individually controlling their quantum state, realizing what is called a...
The historic first detection of gravitational waves from colliding black holes far outside our galaxy opened a new window to understanding the universe. A...
A team led by Austrian experimental physicist Rainer Blatt has succeeded in characterizing the quantum entanglement of two spatially separated atoms by observing their light emission. This fundamental demonstration could lead to the development of highly sensitive optical gradiometers for the precise measurement of the gravitational field or the earth's magnetic field.
The age of quantum technology has long been heralded. Decades of research into the quantum world have led to the development of methods that make it possible...
02.05.2018 | Event News
13.04.2018 | Event News
12.04.2018 | Event News
23.05.2018 | Life Sciences
23.05.2018 | Physics and Astronomy
23.05.2018 | Materials Sciences