Interesting facts about concrete
The source of the photo
Entertaining materials about concrete, its properties and application on Geektimes is written enough. For example, about the first house printed in Russia, I read it here. I believe my material here will be very appropriate.
Under the cut:
- Who built the first monolithic house;
- Why in the USA roads serve 30 years;
- Ships made of concrete;
- Transparent concrete;
- and other interesting facts.
For starters: in 1917, the Norwegian engineer Nikolai Fegner created the first self-propelled marine vessel “Namsenfijord” made of reinforced concrete. During World War II, 24 reinforced concrete vessels and 80 barges were built in the USA.
Reinforced concrete barge on the Riga pier. Photo Source
Very first concrete
The earliest concrete dates back to 5,600 BC. On the banks of the Danube, archaeologists have found a hut built from mixtures of gravel, sand, water and cement. And the floor thickness in it reached 25 cm. A good example of monolithic construction without special equipment.
The pyramids were cast from concrete
Assumptions that the pyramids were built of concrete are not new. At the end of the last century, a Swiss professor of chemistry, Joseph Davidowitz suggested that there is no particular secret to the construction of tombs of the pharaohs - they were erected thanks to concrete pouring. Not so long ago, inside one of the blocks standing in the pyramid of Cheops found human hair belonging to an ancient builder.
All roads lead to Rome
Many roads built by the Roman Empire were built in swampy or water-abundant areas. As it turned out, back in the III - II centuries BC the ancient Romans already knew how to make concrete hardening in water. It was based on lime and ash of volcanic origin.
The first monolithic house
The first concrete house was built by Edison's cement company in Portland. The inventor decided to rid the city of slums and help the family of every working person to get a durable fireproof house. Relatively inexpensive.
The price for a monolithic house with a pipeline, a bathroom and other amenities was about $ 1,200. This is about three times less than the price of a brick house.
But, despite the fact that Edison cement was used in the construction of many structures around New York during the construction boom in the early 1900s, concrete houses did not take root.
There were three reasons:
- Molds and equipment required for construction required large financial resources at the start, and few companies could afford it.
- Some families did not want to move into homes that were advertised as new housing for those living in slums.
- The houses were just ugly.
As a result, Edisson himself became the first resident of such a house.
Why in the USA roads serve 30 years
America is a country of roads. But 55,000 miles of American highways are not asphalt at all, but flooded with high-quality concrete that is not afraid of moisture and frost. Therefore, the cars that drive them have a much longer service life than those that move on asphalt. The first concrete road was laid in the United States in 1930, in Indiana, and then in Illinois in 1940.
US roads are classified from the most significant and passable to less significant:
- Interstate Highways (indicated by index I),
- US Highways (US),
- State Highways (in this case, TX),
- FM roads (FM stands for Farm to Market),
- Local Roads (this group includes other roads, such as Road (Rd), Avenue (Ave), Junction (Jct) and others).
Roads with indices I and US are made of concrete. The largest flow of transport and cargo goes along them. But there is a small feature: some roads are covered with asphalt. But this is only an appearance: concrete is under the asphalt. This is done to extend the life of the road and delay the repair after wear of the concrete pavement. It is more difficult and more expensive to block the road with concrete than asphalt.
The choice in favor of concrete was made because of its strength, durability, unpretentiousness to long-term load and the advantage of long-range fighting. Cons - the difficulty of laying and repair. In the case of asphalt, the road is ready for traffic in 7-8 hours, and a concrete road requires several months of operation.
Bridge and concrete roads serve up to 30 years without major repairs, asphalt roads - up to 10 years, and then, if they are properly laid.
Concrete climate control
Thanks to the light color, concrete reflects light 33–50% more than asphalt. Thanks to this, the Atlanta city authorities managed to lower the average daily temperature in the city by 4 ° C. Decades of street research conducted in the mid-1980s. in Kansas, showed that the cost of maintaining asphalt pavement is nine times higher than concrete.
Concrete is the most sought after material in the world. About 6 billion cubic meters of this building material are manufactured annually in the world. If we take into account that the number of earthlings is approximately the same, then it turns out that every year about 1 m3 of concrete is released per inhabitant of the planet.
It sounds strange, but reinforced concrete was used to build boats and ships. The material was patented in 1848 by the Frenchman Joseph Monier. A few years later, at the World Exhibition in Paris, a rowboat made of reinforced concrete was demonstrated. Also a French inventor. Link to the picture at the beginning of the article.
Concrete tennis table
A few days ago I came across a picture of a ... concrete table tennis table. The author of the creation was a design studio from Barnaul. You can read about how they did it here . The material has interesting details, for example, on how to make the surface of a countertop smooth, what a mesh and other subtleties should be.
A young inventor from Israel (Aron Losonczi) invented "transparent" concrete by adding fiberglass to the composition. As a result, the new material transmits light and looks much lighter while maintaining its properties.
Share other interesting facts in the comments.