How Tokyo Made Itself Earthquake-Proof

Summary

This video explores the devastating impact of the 7.8 magnitude earthquake that struck Turkey and Syria, highlighting the need for earthquake preparedness in seismically active areas. It dives into Japan's innovative earthquake-proofing methods, from basic standards for low-rise buildings to advanced techniques in Tokyo's skyscrapers, such as seismic dampers and rubber legs that allow buildings to sway independently. Additionally, Japan's earthquake detection system provides valuable seconds for citizens to prepare. The video also briefly discusses how technology can help protect lives and infrastructure in earthquake-prone regions.

Takeaways

• 😀 A 7.8 magnitude earthquake earlier this year was the deadliest in modern history for Turkey and Syria, causing over 75,000 buildings to collapse.
• 😀 Earthquakes like the one that hit Turkey are common in certain regions, particularly the Pacific Ring of Fire, which is the most seismically active area on Earth.
• 😀 Tokyo, the largest city in the world, is built in an earthquake-prone area, but it has implemented rigorous earthquake-resistant measures to prevent mass destruction.
• 😀 Every building in Tokyo must adhere to one of three levels of earthquake resistance, with some older buildings being exceptions.
• 😀 The most basic earthquake-proofing standard in Japan is the 'taen' level, which ensures basic sturdiness against smaller earthquakes but doesn't prevent significant shaking.
• 😀 The next level, called 'station', involves advanced systems like seismic dampers to reduce the swing and vibrations in tall buildings.
• 😀 Some buildings, like the Tokyo Sky Tree, use a central column for seismic dampening, a technique dating back over a thousand years in Japan.
• 😀 The highest level of earthquake resistance in Tokyo, known as 'mention', involves isolating buildings from the ground using thick rubber legs to allow them to sway independently from seismic movements.
• 😀 Tokyo's infrastructure includes a vast network of seismic sensors that provide real-time data, giving the city around 30 seconds to prepare for an earthquake by halting trains and alerting citizens.
• 😀 While predicting earthquakes is impossible, the technology used in Japan allows for early warnings based on the detection of p-waves, the first tremors that precede the more destructive s-waves.

Q & A

What was the impact of the 7.8 magnitude earthquake that hit Turkey and Syria?

The earthquake was the deadliest day in modern history for both Turkey and Syria, causing the destruction of more than 75,000 buildings.

Why were Turkey and Syria unprepared for such a large earthquake?

The region hadn't experienced a large earthquake in over 80 years, leading to a lack of preparation for this type of disaster.

What is the Pacific Ring of Fire, and why is it significant in terms of earthquakes?

The Pacific Ring of Fire is the most seismically active region on Earth, where frequent earthquakes occur due to tectonic plate movements. It's significant because regions within it, like Japan, experience frequent and large earthquakes.

How does the design of Tokyo's buildings help mitigate earthquake damage?

Tokyo's buildings are designed with earthquake-resistant standards, including different tiers of earthquake proofing, such as the basic 'taen' standard and more advanced methods like seismic dampers and rubber supports for skyscrapers.

What are the three tiers of earthquake resistance used in Tokyo's buildings?

The three tiers are: 'taen' (basic earthquake resistance), 'station' (which includes seismic dampers like industrial springs or swinging eggs to counteract building sway), and 'mention' (the highest tier, where buildings are isolated from the ground using rubber legs).

What is the role of seismic dampers in high-rise buildings in Tokyo?

Seismic dampers counteract the sway of tall buildings during earthquakes. They either use industrial springs or massive swinging objects (like a giant egg) to stabilize the building and prevent collapse.

How have historical Japanese buildings like pagodas influenced modern earthquake-proofing designs?

Japanese pagodas were designed with a central column (ashin bashira) acting as a seismic damper. This ancient concept is still used in modern skyscrapers, such as the Tokyo Sky Tree, to provide stability during earthquakes.

What technology does Japan use to detect and respond to earthquakes?

Japan uses a network of 4,235 seismometers across the country, which detect the initial waves of an earthquake (p-waves) and provide up to 30 seconds of warning before the destructive waves (s-waves) arrive.

Why is the 30-second warning so important in Japan's earthquake preparedness system?

The 30-second warning allows time for critical actions, such as halting trains to prevent derailments and broadcasting safety alerts to the public, giving people a chance to take cover.

What is the role of the Brilliant course mentioned in the video?

The Brilliant course offers an interactive way to learn about the physics behind everyday phenomena, such as how planes fly and how skyscrapers are designed to withstand earthquakes, helping users understand complex concepts in simple terms.