By the time you read this sentence, the global construction industry has made more than 19,000 baths filled with concrete. In one day, the volume of concrete made would be the size of China's Three Gorges Dam. Only within a year, the concrete produced by the construction industry will fill every corner of England.
In the list of most used materials on Earth, concrete ranks right behind the water. If the cement industry is a country, it will be the third largest carbon discharge in the world with 2.8 billion tons, second only to China and the United States.
Concrete is the foundation of a modern development, the roof covering the head of every fortunate individual with a house, an artificial shield that protects people from the wrath of nature, which is a building material. should provide infrastructure for all essential industries: health, education, transportation, energy and all industries.
Concrete is a means for us to tame wild nature. The armor layer protects humanity from elements. But they are also things that cover the fertile soil that could become a cultivated land, sealing rivers that could have been an endless source of life for living things; The concrete soon became the element to stop the natural development path, they hardened to become a gray layer covering the surface of the Green Planet.
According to calculations by the US National Academy of Sciences, it is more likely that humanity has surpassed the threshold of carbon in concrete more than the total carbon content in plants on Earth. In a more understandable way, what we build has grown beyond what Mother Nature has cultivated for millions of years.
The total amount of plastic produced during the last 60 years was 8 billion tons, the cement industry created more than that in just 2 years. But even though the concrete problem is extremely difficult and even more than plastic waste, most of us still take it lightly. Concrete is not derived from fossil fuels, they do not creep into the whale stomach or pollute the coast, scientists do not see traces of concrete in the human body. But the relationship between people and concrete is deeper than we think.
The solid characteristics of concrete are what make people feel reliant. It is both heavy and durable, and is the perfect foundation to build the modern world that can minimize the destructive nature of nature. When combining concrete with steel, we have a huge architecture that helps to hold water, to obtain strong skyscrapers, a solid and reliable road bridge, with electricity network reaching all places.
Concrete is both a friend and an enemy, not knowing which way; For decades, it has prevented nature but multiplied the effects of nature several times. Take the example of two floods in New Orleans after Hurricane Katrina, in Houston after Hurricane Harvey: the consequences are more severe because of the slow drainage rate of the street, not with the floodplain, and the drainage system. not enough to meet the needs of the climate change period.
Concrete protects people from extreme weather events, but they are also making the climate worse. According to the study of Chatham House, which focuses on the study of worrisome international issues, the production of concrete produces 4-8% of global CO2. There are only three things that surpass concrete in this ranking, namely coal, oil and gasoline. Half of the CO2 emitted in the above 4-8% comes from the clinker production process (Vietnam is also called clinker), this is the most energy-consuming phase in the cement making process.
Discharge of CO2 is easy to understand, but the aspects affecting other environments of concrete have not been thoroughly studied. Concrete is a thirsty year-round monster, accounting for 1/10 of the water used by the global industry. The consequence of this is the lack of drinking water and irrigation water, because 75% of the water used by cement industry is in the areas of frequent drought.
In big cities, concrete absorbs heat from the Sun, keeps emissions from vehicles and from air conditioning; At the very least, their ability is still lower than asphalt.
Concrete is also the agent that makes lung disease worse by inhaling silicon, contributing significantly to the harm of respiratory disease in general. Dust from limestone quarries and cement plants is also a noticeable source of pollution, not to mention vehicles, material ferries between polluted sites. Speaking of the ferry, sand mining, which is likely to heavily affect the riverbed and the beach, is now linked to organized crime and heartbreaking bloodshed.
This is not all the impact of concrete. To build roads and high-rise buildings, we destroy the natural mother's infrastructure without any measures to replace the inherent biological functions; every apartment grows, the soil is less fertile, the pollination of plants is difficult, flood water and standing water appear more after the heavy rain, the ability to produce oxygen decreases, Clean groundwater becomes more scarce.
Concrete pulled the human civilization to reach the sky, reaching 163 floors of Burj Khalifa, creating a place in mid-air. By the way, concrete also pulls up the amount of greenhouse gases released to the environment, occupied land for housing, natural habitat is strangled by cold hands of concrete. Many scientists believe that the biodiversity crisis is worse than the chaos of climate change, and the power behind the biodiversity crisis is to turn the natural environment into cultivated land, into zones. industry discharges toxic smoke, into lavish residences.
The Pantheon Temple and the Roman Coliseum in Rome are two examples of the longevity of ancient concrete, the combination of sand, gravel, water, lime and the temperature of a kiln. By 1824, Joseph Aspdin applied for a patent for a new type of cement, called "artificial stone" with the ability to change modern industry. Later, it was combined with piles or wire mesh to form reinforced concrete, becoming an indispensable component of the high architectural buildings of the time, including the Empire State Building.
After World War II, when houses were heavily destroyed by war bombs, concrete had to flow into rivers so that people could rebuild what had been destroyed by themselves. In 1950, the production capacity of cement was equivalent to that of steel; Since that time, cement production has been multiplied by 25 times, the growth rate is 3 times that of steel.
In the beginning, it was a cheap material, which could be mass-produced to rebuild the cities that had been bombarded by fire. Time permeated, concrete turned into a foundation for the speed of miraculous economic development of modern times. The blood of every essential foundation for life today has the flow of concrete.
Look at Japan to feel the stuffy of concrete. During the recovery period after the war, the country was rich in history to make use of concrete to rebuild the country: long-distance high-speed trains, large roads that cut through dense urban areas, here it's a new school, sports center, stadium for the 1964 Olympics.
But the stamina of nature is limited, we can only cover a certain amount of concrete before the environment is destroyed. In the book Dogs and Demons, author Alex Kerr has lived in Japan for a long time: big projects "cause no small damage everywhere, from mountains, rivers and lakes to ponds – and Unexpected high level of damage. This is the reality of modern Japan facing, worrying figures than ever.
According to data collected by Alex Kerr, the amount of concrete in every square meter in Japan is 30 times higher than the US. "I am talking about a country the size of California, but it covers up the same amount of concrete as the entire United States."
Those who want to honor traditional culture and environmental concerns are ignored. The gray concrete layer is against the traditional Japanese ideal, but it is a necessary barrier to nature itself: it is understood that with dense earthquakes and tsunamis, they need a barrier to prevent his home is flooded.
Sadly, that makes the 2011 disaster in Japan more painful. The barrier walls in Ishinomaki, Kamaishi and Kitakami were defeated in just a few minutes, 16,000 people were killed, millions of buildings were destroyed or badly damaged, the poetic streets of the seaside now flooded with ships drifting back from offshore.
Japan learned from … a thicker, higher wall range. Engineers claim that a 12-meter-tall concrete slab will prevent it, or at least slow down the tsunami power, but locals are the ones who understand the power of nature best: they once heard the words promised the same, then saw the wall fall down after just a few minutes against nature. Environmentalists claim that mangroves will be a more effective way of preventing tsunami, but are more environmentally friendly, the coastal people agree, because they dislike the gloomy gray wall that blocks the coastal people with immense ocean.
"The wall gives us a sense of backwardness, even though no one has done anything wrong," Atsushi Fujita fisherman told Reuters.
But no one can blame it, because this is an inevitable thing that happens on every part of the Earth. Concrete has been and remains the material paving the way for development. In theory, one can look at the progress of humanity through economic and social indicators, such as the average life expectancy, the coverage of education. But for the authorities, the total domestic production is the national growth target. GDP shows the position of an international country, and concrete is an indispensable catalyst to affirm its national stature.
But every country does. In the process of development, heavy capital construction projects have many benefits equivalent to a boxer putting more muscles on him. But when an economy was solid, concrete turned into an energy-boosting drug that pumped into an aged athlete, who was harmless.
America of the 30s under Roosevelt, they built the greatest concrete project, up to that time. It is claimed that Hoover Dam will last longer than human civilization.
During the 1997-98 Asian economic crisis, Keynesian economists advised the Japanese government to create GDP growth by "digging a big hole, filling it with concrete, pits The bigger the better ". This will create profits, jobs and thereby increase the living standards of the people. Between complex economic theories and massive time-bound buildings, concrete is always a cohesive substance.
But both examples of the past mentioned are too small when compared to what is happening in China – the concrete power of the 21st century and is the most obvious example of building materials in place. How to change a country. The Chinese mixed concrete at a rapid pace: since 2003, every three years, Chinese people have created concrete by the number of Americans obtained during the 20th century.
Today, China uses half of the concrete produced. They are catalysts for China's rapid growth, turning projects on paper into large urban areas, with the amenities of roads, bridges, giant shopping malls and scrapers. God.
But like the United States, Japan, South Korea or any other developed country, China has finally reached a milestone of "pouring concrete into roads that is more harmful than good." Scattered throughout China are buildings waiting to be "favored": the giant airport in Lu Luong only serves 5 trips / day, the bird's nest stadium is much more celebratory than practical.
The abandoned architecture blocks not only lose the city beauty, but also burn money into maintenance and routine maintenance. Just build more, and keep on maintaining, obviously will cost reinforced concrete, and waste more toxic waste into the environment. Mr. Yu Kongjian, a Chinese architect said that the big buildings also strangled the natural vitality: fertile soil is occupied, the stream of water loses the ability to filter dirt, mangrove forest blocks the waves disappear, The erosion protection forest gradually disappears.
Mr. Yu calls this a threat to "ecological security". It was he who was the first flag in the war against the concrete force, trying to limit the call to eliminate unnecessary construction near the alluvial grounds and the area of natural vegetation. In the book The Art of Survival (The Art of Survival, named after the famous Suicide of the World History), Yu points out: "The modern urbanization process we are following in this time will lead. to the doom ”.
Yu asked the big politicians who gradually realized the instability of the current growth model, but the official moves from the authorities are still limited. One of the difficult factors: 55 million workers are working in the construction industry, if cutting concrete to reduce pollution, the number of people equivalent to the UK population will suddenly lose their jobs, the consequences will be unpredictable without effective coping plans.
The danger is clear, but developing countries can't help but follow the trend. India and Indonesia have just entered the development stage that needs more concrete. In the next 40 years and by the current speed, the amount of large construction on the Earth's surface will double. This is a double-edged sword:
Tongue is beneficial: the concrete substrate will cover the mud layer, environmental scientist Vaclav Smil estimates that parasitic diseases in poor rural areas reduce by 80% when concrete works destroy the habitat of signed organisms born.
The other blade cut straight into Mother Earth. Each new concrete platform appears to be a tile for the path to the collapse of the ecosystem.
Chatham House estimates: with the current urbanization rate, population growth and economic development, global cement production will increase to 4-5 billion tons / year. According to the Global Economic and Climate Committee, if developing countries continue to invest in large construction projects to equal the average world development, the construction industry will release 470 more. giga-tons of carbon dioxide in 2050.
This act of discharge will violate the Paris climate treaty that a series of countries have signed, all promising the annual carbon emissions of the industry.
cement industry must be down 16% by 2030. When the ecosystem is heavily affected, the creatures living on the Earth will receive enough.
In a report published last year, Chatham House called on the construction industry to find ways to improve cement production processes: reduce emissions, use renewable materials, use energy efficiently, find objects. materials for clinker replacement and application of materials that can hold carbon (the final element is still too expensive, in the process of testing and has no large scale application).
Architects believe that making small buildings to save materials, using concrete substitute wood is a good choice. This is when mankind extends out of the "concrete era", stopping caring about the way the building looks, looking at the dangers they bring.
"Concrete is beautiful and flexible, but unfortunately because it contains all the risks of environmental degradation," said architect Anthony Thistleton in the Journal of Architects Journal. "We need to think carefully about the material being used, and the consequences it leaves."
But engineers do not believe in the application of replacement materials. Steel, asphalt and roofing sheets also consume more energy to make than concrete. Not to mention the declining forest area, where is the wood for replacement materials?
Phil Purnell, professor of materials and architecture at the University of Leeds said that the world has not reached the "peak concrete" threshold.
Mr. Purnell proposed another way, which is to maintain existing structures more effectively, including the removal of concrete also needed to be calculated. Currently, most of the excess concrete will be smashed and broken into blocks. We can improve this way by classifying concrete, bringing it to suitable construction facilities for recycling. Purnell's partner at Leeds University is also studying a new type of concrete that emits less carbon.
Finding new materials, finding new ways to use them will be useless, if our way of thinking doesn't change. It's hard to change the social structure that has been successfully built for hundreds of years on solid concrete. When you understand that concrete background can lead to the collapse of human civilization, perhaps we will awaken to act.
Refer to The Guardian, Reuters, NY Times, ChathamHouse