Steel buildings are well known for their resistance to extreme weather conditions such as high winds, hurricanes, and tornados. In fact, the evidence is on record of how well these metal buildings stand up to major weather disturbances. What is left standing and still intact after major disasters such as hurricanes, are the steel buildings built up to code and made of high-grade steel.
But how do steel buildings perform during earthquakes? The favorable performance of steel buildings in numerous violent earthquakes in the country (San Francisco, Santa Barbara, and Long Beach), has contributed to their proliferation. Engineers became convinced that steel is the material of choice as far as building earthquake-resistant structures are concerned.
There are two theories on the impact of earthquakes on steel buildings. One line of reasoning states, that an earthquake is a result from the movement of the plates, below the earth’s surface, against each other. This creates seismic waves that travel to the surface and move out from the epicenter of the earthquake.
The other theory is largely based on inertia or the tendency of a body at rest to remain at rest unless acted upon by a force. During an earthquake, the bottom of steel buildings moves with the earth as the surface begins to move away from the structures. But inertia keeps the buildings in the same spot for a while. It has been observed that the amount of seismic force that strikes is relatively greater for steel buildings that have more weight.
On the other hand, experts agree that the amount of seismic activity is likewise determined by other factors including the type of ground that the steel buildings stand upon. There are ground characteristics that are more susceptible to seismic activity. In addition, the rigidity of buildings is another factor. The good news is, steel buildings are designed with lateral load resisting features that make them resistant to earthquakes.
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