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In the earthquake, the ground will vibrate, twist, rise and fall, and change the direction and speed of the movement every moment. This kind of violent and disordered ground movement makes the house in motion. The house is displaced on the foundation and some structural parts may tip over. Under the action of the earthquake, the house finally split because of the cracks. Then in the wood structure house, if the foundation of the house is stable and the structure is appropriate, the house can effectively resist the load caused by the earthquake and reduce the earthquake damage.
As a kind of structural material, the seismic performance of wood is obviously better than other materials. The natural flexibility of wood also enables it to effectively withstand the seismic force. Wood is light and high-strength, so the energy generated by ground acceleration on wood buildings is not as large as other buildings, and the inertial force generated by wood structure buildings in the earthquake is low, so the damage suffered by wood structure buildings is small. Another additional advantage of wood frame systems is that they are more flexible than other materials and can absorb and dissipate energy.
Eight towns in Wenchuan County were almost razed to the ground, large areas of urban areas were buried and houses collapsed. In history, the damage to buildings caused by all the previous earthquake disasters is huge. For this reason, Japan, as an earthquake prone country, adopts the Countermeasures of large-scale use of wooden structure houses and reasonable shock absorption.
The wood structure has great toughness, and because the box structure of the wood structure villa divides the force equally, its own structure is light, and has strong elastic recovery, which has strong low resistance to the instantaneous impact load and periodic fatigue failure. Therefore, the seismic force absorbed in the large earthquake is small, and when the foundation displaces, it can be reset by its own elasticity without collapse.
During the earthquake in Kobe, Japan, and in the United States, the wooden buildings were slightly deformed and never collapsed. Even under the strong earthquake force, the wooden structure building is pushed forward several meters or the earthquake force makes it throw away from the foundation, and it is still intact without scattering. The integrity of wood structure is proved. After the Kobe earthquake, the Japanese government made it clear that all the residential buildings in North America must be wooden structures.
Modern wood structure houses have been decorated inside and outside with building materials on the basis of existing buildings, such as wrapping the outer surface of wood structure with breathing paper, so that the temperature and gas in the structure can be discharged smoothly, and avoiding the outside rainwater from invading the inner structure, and the exposed wood structure shall be subject to necessary anti-corrosion treatment, etc. These measures can make the service life of wooden structure villa reach more than 70 years. Wooden structure houses have the advantages of light structure, anti settlement, anti-aging and fully accept the earth's magnetic field. Under the premise of proper use and maintenance, wood in wood structure is the main structural material with stability, long life and strong durability.