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It is likely before many months have passed to find out for sure what caused the collapse of the Champlain Towers South building last week in Surfplan, Florida, which killed at least 18 people. But it is already clear that at least one culprit was failing in the concrete. In 2018 an engineering company warned that the concrete under the pool and entrance unit of the building had “significant structural damage” and found “numerous cracks” in the underground car park. A few months ago, the president of the building’s condominium association wrote, “The deterioration of the concrete is accelerating.”
Although the sudden collapse of the wholesale building is very rare, it is a problem of crushing concrete it is not at all. It is a slow crisis affecting the whole world. It could replace billions of tons of concrete in the form of concrete buildings, roads, bridges and dams in the coming decades. This will cost billions of dollars and generate huge amounts of carbon emissions that will drive climate change.
Concrete, basically just sand and gravel glued to cement, is the most widely used building material on earth. Every year we throw enough 88 meters high and 88 meters wide to build a wall around the equator. That’s largely because the number and size of cities are exploding. The city’s population has quadrupled since the 1960s to more than 4 billion, and is still rising. Every year we are adding the equivalent of 10 New York cities to the planet.
There is no city without fast-growing concrete. It’s a relatively inexpensive and inexpensive way to create roads, bridges, dams, and fairly solid and fairly fast sanitary housing for a large number of people. Today, approximately 70% of the world’s population lives in concrete structures.
But none of these structures will last forever. Concrete fails and breaks in dozens of ways. Heat, cold, chemicals, salts and moisture attack the seemingly strong artificial rock, working to weaken and break it from the inside. (Rising temperatures and atmospheric carbon levels are expected to create things worse.)
This threatens not only apartment towers, but also concrete-based infrastructure. A 2021 report from the American Society of Civil Engineers found this More than 20,000 concrete bridges in the U.S. are structurally deficient and nearly half of the nation’s public roads are in a “poor” or “poor” state.
Things are worse in many developing countries where construction standards are low and rules are often ignored. To reduce costs, builders often use unwashed sea sand to make concrete. These grains are cheaper, but are covered with salt that dangerously erodes the coat. Dozens of people were killed in the 2010 earthquake in Haiti. Poor concrete was also a key reason for the collapse of a factory that killed more than 1,000 people in Bangladesh in 2013. According to The Financial Times, as much as 30 percent The level of Chinese cement is so low that there are dangerous structures known as “tofu buildings”. One of the reasons many schools have collapsed as a result of China’s 2008 Sichuan earthquake is to make concrete, killing thousands of people.
All this is frightening, given that most of the world’s concrete has only been laid in recent decades, and most of it in the developing world — China in the first place. Only China used more cement between 2011 and 2013 than the United States in the twentieth century. Than what they used throughout the century. As a result, writes economist Vaclav Smil: “The world after 2030 will have an unprecedented burden in the face of the concrete collapse … The future replacement costs of the material will be trillions of dollars.”
The excavation of billions of tons of sand and gravel needed to make all the concrete will inevitably damage the riverbed, lake bottom and floodplain. The extraction of poorly regulated sand and gravel in several countries has wiped out a large number of fish and birds that live in rivers, damaged coral reefs and collapsed riverbanks. The industry has created a huge black market corruption and violence.
As if all this were not enough, the manufacture of all this concrete will have a major impact on the environment. The cement industry produces 5-10% of the world’s carbon dioxide emissions, behind coal-fired power plants and automobiles, as a source of global warming gas.
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