Fortunately, all structures in Japan are obliged to have an earthquake-resistant structure, which means that new construction may only be permitted if it adheres to strict earthquake-proof requirements established by law. Older buildings must meet stricter standards than newer ones.
The main threat from earthquakes to buildings in Japan is not the damage that can be done by an initial shock but the effect of aftershocks. Even large earthquakes don't cause many deaths or injuries because people take sensible precautions such as staying away from damaged buildings. It's the aftershock sequence that does the most damage: long periods without sunlight, water and food, with only limited supplies reaching those who need it most.
After a major quake, it can take years before buildings are inspected for damage and repairs carried out. If a house isn't repaired then it will likely be demolished, leaving its occupants homeless.
Japan's building code was revised in 2005 in an attempt to reduce the number of disasters such as the one that struck Kobe in 1995. Before then, builders were required to ensure structural stability against ground vibration only when measuring the force of the earth's gravity on their projects. The new code requires them to consider other factors too, such as wind pressure and temperature changes that can cause buildings to collapse.
The revision also included important changes designed to prevent future disasters.
Earthquake-resistant structures Given the frequency with which earthquakes occur in Japan, all houses are designed to endure some amount of vibration. The iconic Tokyo Skytree was designed to defy natural calamities by emulating the form of old wooden pagodas that have weathered generations of earthquakes. Its strength comes from its design and its use of advanced materials, including transparent polycarbonate skin.
After the 2011 earthquake and tsunami, many countries donated equipment and experts to help Japan rebuild and strengthen its infrastructure against future disasters.
In fact, after the 1923 earthquake and tsunami, most Japanese homes were rebuilt with stronger concrete buildings. But as cities expanded and standards fell, new houses were constructed using outdated techniques. This makes modern-day Japan's biggest threat of flooding from typhoons and mudslides instead of earthquakes.
After World War II, building standards improved but not enough. According to a report published by the United Nations Office for Disaster Risk Reduction, over 70 percent of homes in Japan did not meet current seismic standards. That's more than any other country in the world except Haiti.
In order to prevent further damage from future earthquakes, the government has launched a campaign to encourage people to build quality homes that will last for many years after they are built. Funding is available through local governments to help residents pay for public safety campaigns, training for builders and structural upgrades.
As a result, there is an urgent need to include earthquake-resistant technology into earthquake-proof structures in order to reduce fatalities from structural damage or collapse caused by an earthquake. Earthquakes are a natural phenomenon that cannot be avoided. There is little notice before an earthquake hits an area. The only way to avoid injury or death due to an earthquake is not to be in the path of the oncoming earth's surface.
Even buildings with strong foundations can suffer major damage if the ground under them moves more than expected during an earthquake. Modern building techniques and materials have greatly improved since the 1989 earthquake and fire that destroyed much of San Francisco, but every effort should still be made to create buildings that will survive such events.
The good news is that modern construction practices have been improving overall earthquake resistance for many years. New building codes require retrofitting existing buildings with stronger materials or installing special equipment such as seismic isolators or dampers that will prevent damage during an earthquake.
In addition, some cities have started requiring new buildings to be constructed with seismic insulation, which reduces noise and energy transfer during an earthquake. This also helps prevent damage to other parts of the building during an event.
Finally, new research being done on earthquake resistant building design can help us create even more resilient homes and offices in the future.
Japan is undoubtedly the most earthquake-resistant country in terms of engineering standards. A big earthquake, on the other hand, cannot be made safe by engineering. (Namazu, the mythological gigantic catfish responsible for earthquakes. Kashima, the Shinto deity, holds him back. There are stories that say that one day Namazu will break free from his restraint and cause a massive disaster.) The reason Japan has not suffered any major earthquakes for 1000 years is because their infrastructure was destroyed in major temblors over and over again until engineers created systems that were able to withstand such force.
Since World War II, Japan has been rebuilding itself after major disasters have taken away much of its productive capacity. The country's economy has been dependent on exports, but when countries around it suffer major devastation, they have less incentive to buy Japanese products. However, Japan has managed to remain strong despite these challenges. It still imports some energy resources, but it mostly relies on nuclear power for electricity production. The country also receives help from outside sources when major disasters occur. For example, after the 2011 tsunami damaged much of the electrical system along with many nuclear plants, Japan turned to China for help. In return, Japan promised to buy large amounts of Chinese oil and natural gas.
Overall, Japan has achieved success in engineering mitigation measures through experience. They have proven how vulnerable their society can be, so future developments focus on prevention rather than relief.