Concrete

Brick (68)
Building material (27)
Cement (27)
Clay (45)
Concrete (97)
Cornerstone (17)
Insulating material (9)
Mortar (25)
Plaster (12)
Sealant (6)

Synopsis: Civil engineering: Civil engineering generale: Building materials: Concrete:

By combining steel and concrete in prefabricated composite structures with reinforced concrete slabs, the European union (EU)- funded Preco-Beam project found a way to shave months off construction times

"is the way the steel connects to concrete, by a structure known as the composite dowel."

which connects steel and concrete: namely an I-section which can be divided into two steel T-beams by one simple cut."

and programmed to construct pre-designed concrete structures and their relevant sub-components--was put forward by Dr. Behrokh Khoshnevis of the University of Southern California as far back as 2009.

and medical devices to structural components for the automotive civil and aerospace industries. he cellulose nanocrystals represent a potential green alternative to carbon nanotubes for reinforcing materials such as polymers and concrete.

Seconds later a series of high-pitched chirps ricocheted off a nearby concrete wall an indication that the test worked.

While growers can use the sensors to monitor water in soils for their crops civil engineers can embed the chips in concrete to determine optimal moisture levels as the concrete cures. ne of our goals is to try

#For better concrete, do did as Romans University of California Berkeley rightoriginal Studyposted by Sarah Yang-Berkeley on June 5 2013uc BERKELEY (US)# Ancient Roman structures that have withstood the elements for more than 2000 years

The discovery could help improve the durability of modern concrete which within 50 years often shows signs of degradation particularly in ocean environments.

The manufacturing of Roman concrete also leaves a smaller carbon footprint than does its modern counterpart.

The process for creating Portland cement a key ingredient in modern concrete requires fossil fuels to burn calcium carbonate (limestone) and clays at about 1450 degrees Celsius (2642 degrees Fahrenheit.

The production of lime for Roman concrete is much cleaner requiring temperatures that are two-thirds of that required for making Portland cement.#

#Roman concrete has remained coherent and well-consolidated for 2000 years in aggressive maritime environments#says Marie Jackson a research engineer in civil and environmental engineering at University of California Berkeley.#

and colleagues characterized samples of Roman concrete taken from a breakwater in Pozzuoli Bay near Naples Italy.#

Of particular interest to researchers is how Roman#s underwater concrete endured the unforgiving saltwater environment.

The recipe for Roman concrete was described around 30 BC by Marcus Vitruvius Pollio an engineer for Octavian who became Emperor Augustus. The not-so-secret ingredient is volcanic ash

and made it an integral part of the concrete. Also key was a very rare hydrothermal mineral called aluminum tobermorite (Al-tobermorite) that formed in the concrete.#

#Our study provided the first experimental determination of the mechanical properties of the mineral#Jackson says.

Use of Roman concrete decreased because#as the Roman empire declined and shipping declined the need for the seawater concrete declined#Jackson says.#

#Earth-friendly alternativewhile Roman concrete is durable it#s unlikely to replace modern concrete because it is not ideal for construction where faster hardening is needed.

But the researchers are now finding ways to apply their discoveries about Roman concrete to the development of more earth-friendly and durable modern concrete.

The size of the 3d printer is large enough to construct walls by depositing concrete based material layer upon layer to build a Wall in this video,

and concrete might be needed and its impact on cost. Autocase from Impact Infrastructure adds triple bottom line analysis into the mix.

Have not heard anything concrete yet, "Peiris e-mailed today.)So far, Korea has quarantined close to 700 people to stop the spread of the virus

instead of concrete. his makes it much more cost-effective to build much taller towers, says Smith, Keystone CEO.

They don have to be removed once the concrete is poured, since they can act as embedded insulation for the house.

Conventional turbine construction for instance requires tons of concrete and the use of cranes which can be difficult to maneuver around certain sites.

For example the program has produced the first of a planned series of science centers a simple concrete building outfitted with computers

And instead of pouring concrete foundations and erecting a multistory tower a few people with a truck can inflate the airship on site

#Biologist creates'self-healing'concrete No matter how carefully it is mixed or reinforced, all concrete eventually cracks,

"The problem with cracks in concrete is leakage, "explains professor Henk Jonkers, of Delft University of Technology, in The netherlands."

Secondly, if this water gets to the steel reinforcements--in concrete we have all these steel rebars

"But Jonkers has come up with an entirely new way of giving concrete a longer life."

"We have invented bioconcrete--that's concrete that heals itself using bacteria, "he says. The bioconcrete is mixed just like regular concrete,

but with an extra ingredient--the"healing agent.""It remains intact during mixing, only dissolving and becoming active

"You need bacteria that can survive the harsh environment of concrete, "says Jonkers.""It's a rocklike, stonelike material, very dry."

"The next challenge was not only to have the bacteria active in concrete, but also to make them produce repair material for the concrete--and that is limestone,

"Jonkers explains. In order to produce limestone the bacilli need a food source. Sugar was one option,

When cracks eventually begin to form in the concrete, water enters and open the capsules.

Now Jonkers hopes his concrete could be the start of a new age of biological buildings."

more durable concrete for building materials; and biomimetic materials reproducing the advanced mechanical properties of many natural structures.

In the first case, it must be incorporated when the concrete is poured in those areas of the structure most exposed to corrosion caused by humidity, carbon dioxide or chlorides, among others.

'Living'concrete heals itself using BACTERIA when it comes into contact with water Building repairs

researchers mix them into the concrete along with calcium lactate. When cracks in the concrete appear, and water enters them,

the water'awakens'the bacteria (animated). The bacteria'eat'the calcium lactate and secrete limestone which closes the cracksin conventional,

Water penetrates the steel in the concrete which starts to rust and becomes brittle. Using a type of bacteria that is typically found near active volcanoes,

and near soda lakes like those near Wadi Natrun in Egypt, the researchers mix the bio material into the concrete as it is made.

'The special thing about them is that they form spore meaning they are suited well to the concrete

When cracks in the concrete appear, and water enters them, the water'awakens'the bacteria

and launch the concrete in 2016-although an exact date hasn't been released.''The concrete is perfect for structures

which are difficult to maintain, like underground buildings, motorways or oil rigs,'added Dr Jonkers.''It is extremely durable.

and can survive dormant inside the concrete for years. The team has been nominated for a European Inventor Award t

000psi twice the strength of ordinary concrete and have demonstrated resistance to water and chemical erosion.

Traditional concrete masonry has a high carbon footprint due to its reliance on Portland cement a material responsible for 6 percent of the world CO2 EMISSIONS.

Geopolymers are a new technology that provide an alternative to Portland cement used in concrete and masonry.

This new'thirsty'concrete absorbs 4, 000 litres of water in 60 seconds During the first few weeks of August 2007,

a new type of porous concrete that can absorb up to 4, 000 litres of water in the first 60 seconds,

While permeable concrete has been around for the past 50 years, it's mostly been used under pavements to help with drainage,

Not only can the super-absorbent concrete be used in conjuction with existing concrete-cities can install it so the runoff from regular concrete is fed into the Topmix Permeable

-but it will also be significantly cooler than regular concrete during the hottest months of the year."

so the concrete can only be used in places where temperatures are never likely to dip that low w

it has to be able to make concrete, quantitative predictions about the learner behavior.?Ultimately, we hope that the work can be used to help teachers develop lesson plans

"This concrete, atomic resolution picture of what the pre-fusion machinery looks like and where these antibodies bind provides an important step forward to understanding HIV's biology,

What the engineers came up with was a system of prefabricated concrete covered by solar panels

When you unplug it suddenly you feel like your feet are blocks of concrete says Mooney.

Green Concrete. In the United states a startup called Skyonic is running a pilot plant at a cement mill to reuse carbon dioxide in sodium bicarbonate or baking soda a

and the large amount of steel and concrete needed to keep the apparatus steady makes the approach expensive.

and insulated with concrete to prevent any leakage from entering local groundwater. Bacteria that naturally occur within cowsdigestive tracts are added to the manure,

#Concrete That Heals Itself Concrete and bacteria are seen not often as sharing the same construction armchair, that is,

whether the safety of concrete could be improved using a biological solution. This manufacturing query turned out to be the right question asked at the right time.

a microbiologist, the cracks that form in concrete are not just unpleasant to look at, they can eventually lead to structural failures. he problem with cracks in concrete is said leakage

Jonkers. f you have cracks, water comes throughn your basements, in a parking garage. Secondly, if this water gets to the steel reinforcementsn concrete we have all these steel rebarsf they corrode, the structure collapses.

It has taken Jonkers and his team three years to produce this self-healing prototype, needing to overcome the most obvious obstacle:

The bioconcrete is mixed just like regular concrete but with an extra ingredient the ealing agent.

or oxygen. he next challenge was not only to have the bacteria active in concrete, but also to make them produce repair material for the concrete and that is limestone,

Jonkers explains. In order to produce limestone the bacilli need a food source. Sugar was one option,

When cracks eventually begin to form in the concrete, water enters and open the capsules.

Jonkers said he hopes his concrete could be the start of a new age of biological buildings.

researchers from Delft University mixed the bio material into the concrete along with calcium lactate. When cracks in the concrete appear,

and water enters them, the water'awakens'the bacteria. Once active, the bacteria'eat'the calcium lactate

and brings it down to a concrete level. You look at Watson ability to help pharmaceutical researchers,

A brick wall at the nanoscale January 22nd, 2015atomic placement of elements counts for strong concrete:

#This Futuristic Concrete Heals Itself With Built-in Bacteria Concrete has been a go-to building material since Roman times.

Regardless, cracked concrete is never something you want to see in a building, bridge, or street. At best, it something you want to avoid stepping on (for your mother sake),

a microbiologist at Delft University of Technology, is working on a concrete with built-in bacteria that can fill in cracks as they form.

The powdery substances are mixed then into wet concrete before it gets poured into place. When a crack forms and water seeps in,

or plaster (not built into the concrete) has been around for a few years. But Jonkers and his team have brought actually the concrete out of the lab

and into the real world, using the concrete to build a self-healing lifeguard station. The building has already proved its resilience

cracking and quickly sealing its wounds. Jonkers hopes that eventually more buildings will be built with the biological concrete,

creating structures that will fix themselves instead of degrading into fixer-uppers s

#Computer Chips Can Now Be made From Wood Not quite what we had in mindthe woods are lovely, dark, deep,

Edward H. Egelman with the massive Titan Krios microscope that buried in tons of concrete under Fontaine Research Parkhat interesting and unusual is being able to see how proteins

the massive microscope is insulated within many tons of concrete to provide the stability needed to examine biological samples in previously impossible detail.

or concrete that slowly release the stored heat, and others such as water or ethylene glycol that take in heat

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