How Earthquakes-Proof Buildings Are Designed?

We have built incredible structures and cities throughout history only to see them fall to the forces nature has wrought. Earthquakes are one the most destructive forces on the planet. Seismic waves can cause the destruction of buildings, kill people and cost a lot of money to repair or replace.

The National Earthquake Information Center estimates that there are approximately 20,000 earthquakes per year, 16 of which are major disasters. A magnitude 7.2 earthquake that killed more than 2,000 people in Haiti’s southwest region on August 14, 2021, caused a magnitude 7.2 earthquake. Like other earthquakes, the majority of the damage was caused when buildings collapsed with people inside, so earthquake-proof buildings are a must.

Engineers have developed new building materials and designs over the years to make buildings more resilient to earthquakes. You can read on or skip to the infographic to see how earthquake-proof buildings were designed today. Try out the area calculator for the measurement.

How do earthquakes impact buildings?

Before we can look at the features of earthquake-proof buildings it is important to understand how earthquakes affect man-made structures. An earthquake sends shockwaves through the ground at short, rapid intervals. These shockwaves can travel in all directions. Although buildings can withstand vertical forces due to their gravity and weight, they are not equipped to withstand the side-to-side forces that are emitted from earthquakes.

Horizontal movement causes vibrations in walls, floors, and columns as well as beams and connectors. Extreme stress is created by the difference in movement between the top and bottom of buildings. This causes the supporting frame to burst and eventually the entire structure. This land area calculator will help you with different area shape calculations. 

How to make a building earthquake-proof?

Engineers work to strengthen the structure and prevent earthquakes from happening. Furthermore, the strategy is to have the building move in the opposite direction from earthquakes that release energy. Moreover, these are just a few of the ways buildings can withstand earthquakes.

1. Create a flexible foundation

Base isolation is a way to resist the ground forces. It involves lifting the foundation of the building above the earth. Base isolation is the construction of a building on top of flexible pads made from steel, rubber, and lead. The structure is stable even though the base vibrates during earthquakes. This helps absorb seismic waves and stops them from traveling through the building.

2. Counter Forces with Damping

You may be familiar with shock absorbers found in cars. Engineers also use them in earthquake-resistant buildings. Shock absorbers are similar to those used in cars. They reduce the magnitude of shockwaves and reduce pressure on buildings. Two methods are used to achieve this: vibrational control devices or pendulum power.

• Vibrational Control Devices

This involves placing dampers between beams and columns at every level of a building. Each damper is made up of piston heads within a silicone oil-filled cylinder. The vibrational energy from an earthquake is transferred to the pistons which then push against the oil. The vibrations are then dissipated by the heat and the energy is transformed into heat.

• Pendulum Power

Pendulum power is another common method of damping, which is used primarily in skyscrapers. Engineers suspend a large ball made of steel cables, which connect to a hydraulic system at top of the building. The ball acts like a pendulum to stabilize the building when it begins to move. These features, similar to damping, are designed to counteract the earthquake-induced movement.

3. Shield buildings from vibrations

Researchers are exploring ways that buildings can redirect and deflect earthquake energy. This invention is known as the “seismic invisible cloak”. It involves the creation of a 100-concentric plastic and concrete cloak and placing it at least 3 feet below the foundation of the building.

The rings are able to travel easily as seismic waves enter them. They are then channeled away and dissipated into the ground.

4. Reinforce the Structure of the Building

Buildings must be able to withstand earthquakes by distributing the forces through them. Buildings can be reinforced by shear walls, diaphragms, and cross braces.

These walls are made up of many panels and help buildings maintain their shape during movement. Steel cross braces are used to support shear walls. These beams are capable of supporting compression and tension and can be used to counter pressure and push forces.

The central component of a building’s structural structure is also the diaphragm. The diaphragms are composed of the floors, roof, and decks. They help to remove tension from the floor as well as push forces towards the building’s vertical structures.

Moment-resisting frames offer additional flexibility to a building’s design. These structures are installed between the building’s joints. They allow columns and beams flexibility while keeping joints rigid. The building can withstand the greater forces of an earthquake, while designers have the freedom to design building elements.