What are Earthquake Resistant Buildings? How they Work?

EARTHQUAKE RESISTANT BUILDINGS

An Overview to Earthquake Resistant Buildings

An Earthquake is one among natural calamities that we have to face. Basically it is caused due to sudden shaking caused in the Earth’s crust caused by the movements in the rocks. Due to these movements there is a sudden release of energy that causes the shaking effect. The frequency of the earthquake is measured in seismometers. The shaking may sometimes be minor and sometimes very hard and being hard may cause a great loss to mankind. So as to prevent the ill effects, there are some safety measures that can be taken care of. Following the safety measures can’t completely save us from the destruction of the earthquakes, but can lesser the effect that can cause harm to the people.

Here in this piece of content we are going to discuss one of the safety measures named “Earthquake resistant buildings” that we are opting now a days to remain safe up to much extent from the effects of the earthquakes. So, what basically are earthquake resistant buildings? These are the buildings that are structured in a manner that whenever the earthquakes occur, the building can withstand the effect, thereby causing minimum effect to mankind.

Let’s talk about, earthquake resistant buildings. What actually they are, how they are supposed to work and what are the effects. So, basically these buildings are designed in a way that they can support vertical loads that in turn act as a support for walls, roofs and other collectibles to keep them standing.

Let’s Know the Philosophy behind Earthquake Design?

• If there occurs a minor but frequent shaking, the main parts of the building carrying vertical and horizontal forces should not be damaged, but the parts that don’t carry much loads can face damage that can be repair afterwards.

• If there occurs a moderate but occasional shaking the main parts can face the damage that can be repaired afterwards but the other parts can face the damage that can be replaced after the earthquake occurs.

•If there occurs a strong but rare shaking, all the parts may face severe damage that event can’t be repaired later, but the main concept is that the building should not collapse and not cause or cause a little damage to mankind.

 How Earthquake Resistant Buildings are Different

For a building to be earthquake resistant, it must be configured well, detailed well as well as constructed well, because if lacks in any one of these, it may result in inappropriate resistance. As the normal buildings in practice are made of concrete, horizontal members (beams and slabs) and vertical members (columns and walls) and supported by foundations that rest on the subsoil. The system consisting of RC columns and connecting beams is called a RC frame.

Following are some points to be taken care of while building the same:

·       The very first thing is that the building should be able to sustain as much side-ways motion as possible.

·       Secondly the light weight civil engineering materials should be used, especially for walls and roofs.

·       Apart from it seismic bands should be used as it contains a concrete flat runner at the plinth level of the building and the lintel level of all doors and windows.

·       Last but not the least, use vertical reinforcement in brick walls. This reinforcement should start from the foundation and run through all the seismic bands.

Some techniques that are in practice for earthquake resistance structures are as follows:

·       Base Isolation Method:  This method suits best for hard soil surfaces only. In this method the building is rested on flexible pads. By doing so, when the earthquake comes the building doesn’t move. Types of base isolators used are:

Ø Lead-Rubber Bearing

Ø Spherical Sliding Isolation

In India this technique was first practiced in 1993

·       Energy Dissipation Device:  These devices acts as hydraulic shock absorbers in cars and are used in place of structural elements such as diagonal braces.  When seismic energy passes through them, dampers absorb a part of it, thereby damping the motion of the whole building. Following are some various types of seismic dampers:

Ø Viscous Dampers

Ø Friction Dampers

Ø Yielding Dampers

Ø Viscoelastic Dampers

·       Keeping Building Up Thrust: This technique is recently discovered in Japan. It has been observed that building built in this way survived even in harsh earthquake conditions. In these types of buildings, when earthquake strikes the building, the system dissipates energy in the building cores and exteriors.

Let’s know about some earthquake resistant buildings in the world. Find the listed ones below:

·       Utah State Capitol: It is the house of government in United States

·       Sabiha Gökçen International Airport: The airport is situated in the city of Istanbul

·       Taipei 101: Taipei 101 is formerly known as the Taipei World Financial Center. It is a landmark super soaring skyscraper in Xinyi District, Taipei, and Republic of China.

·       The Burj Khalifa: It is the world’s largest artificial structure located in Dubai, UAE

·       The Yokohama Landmark Tower:  It is located in the Minato Mirai 21 district of the Yokohama city of Japan

·       The U.S Bank Tower: It is formerly Library Tower and First Interstate Bank World Center is located in downtown Los Angeles, California.

·       The Transamerica Pyramid: It is the tallest skyscraper in the San Francisco skyline

·       The Petronas Towers: It is situated in Kuala Lumpur, Malaysia

·       One Rincon Hill South Tower: it is an upscale residential complex on the apex of Rincon Hill in San Francisco, California, United States

·       Citicorp Center: It is an office tower based in New York City, U.S

Areas that are prone to severe earthquakes such as Japan and California etc are more focused towards such techniques and also in process of inventing and practicing much more techniques of the same practice, that are much more advanced in the technical field, and more resistance to severe earthquake situations.

For complete and detailed information regarding the buildings, it is advisable to consult an architect or engineer. We should all make our homes following the same hierarchy. Apart from it schools, colleges, hospitals and other areas where gatherings are high in no. should be taken care of. Most importantly the areas like dams should be given more preference than others. So as to conclude, we can say that, safety comes first beyond anything. So stay safe and make sure that every earthquake cannot convert into a disaster.