On March 11, an earthquake with a magnitude of 9 occurred in the northeast of Japan, causing a tsunami as high as 10 meters to engulf the eastern coastal area of Japan. However, few houses collapsed due to the earthquake itself. Although many houses were moved far away by the waves, they did not fall apart. Many multi-storey, medium high-rise and even high-rise buildings are still standing. The reason why these buildings can stand still is closely related to the earthquake proof technology and measures of Japanese housing construction.

Foundation seismic isolation

In Japan, the technology of "foundation seismic isolation" is widely used in the foundation construction of high-rise buildings, and the anti-seismic buffer devices such as rubber elastic pad or friction sliding bearing seat are installed at the bottom of buildings. For example, Mitsui Real Estate Co., Ltd. sold an earthquake proof apartment with a height of 93 meters in Dushanbe District of Tokyo. High strength 16 ply rubber was used in the periphery of the building, and the natural rubber system was used in the central part of the building. In the event of an earthquake of magnitude 6 or more, the protective device can reduce the stress of the building by at least half.

reinforced concrete structure

In Europe and China, bricks and tiles, which are regarded as the main building materials, have hardly been found in Japanese buildings. The Japanese learned a lesson from the great Kanto earthquake in 1923 and understood that brick buildings can not resist earthquake. Therefore, they use reinforced concrete structure supplemented with light wall materials to replace the original brick structure. Experts in the construction industry believe that the structure of the building can not only be safe and earthquake resistant, but also save energy.

Box design for residential buildings

Japan's ordinary houses adopt the box design, so that when the earthquake occurs, the house will roll over as a whole, not damaged. Professional technical personnel will regularly carry out seismic reinforcement grade assessment of residential buildings, and the government will give appropriate subsidies to residents as appropriate. Most of the roofs of houses in Northeast Japan are made of iron plates, which are much lighter than those made of tiles. In addition, in order to keep out the cold, the openings of doors and windows of Japanese houses are smaller, which makes the rooms more earthquake resistant. It is precisely because the houses collapsed less, which greatly reduced the casualties.