How is the seismic resistance of buildings defined? How can we tell if they are resistant or not?

The buildings all have some degree of adequacy. The question is at what level is this degree of competence that they have. For example, buildings that were built many years ago, say before 1959, were not built to code at all. In our country, let’s say, there are three periods of buildings made with the seismic regulations. The first regulation is from ’59. After the Thessaloniki earthquakes and the ’81 earthquakes in Athens, some additional provisions came in ’84 that were applied to construction from ’85 onwards, and the third period of regulations is from 1995/2000 onwards. The buildings are therefore included in these three periods. What is seismic capacity? And a building built before ’59 has a seismic capacity. It just withstands a small earthquake. A building built to the new regulations also has a seismic capacity, but can it withstand a bigger and stronger earthquake? This does not mean that new buildings are fully seismic resistant and can withstand all earthquakes. They have a level of adequacy that can withstand an earthquake. New buildings can withstand an earthquake (a design earthquake), but there is a chance that another earthquake will come from nature that will exceed the earthquake to which they were designed. What is this probability? 10% in the next 50 years. Therefore we can say that each building has a seismic capacity depending on the regulation which it was made.

Some useful tips that people should know about earthquakes and the buildings they live in.

Houses are not designed based on the Richter earthquake. If someone tells you that this house can withstand 10 Richter, then he has no idea about seismic design of structures. One of the seismic design parameters is the ground acceleration and not the Richter earthquake.

New structures are designed for some level of earthquake. There is a possibility that nature will make an earthquake and overcome the earthquake for which the structure was designed. What is this probability? 10% in the next 50 years. So new constructions are not invulnerable.

The damage that a structure may suffer after an earthquake may also be caused by other causes. For example, wear and tear on materials caused by the environment.

Finally, an earthquake is a natural phenomenon.For example, wear and tear on materials caused by the environment. Like all other natural phenomena, if it takes place in an area where there is no built environment, then there will be no losses. An earthquake becomes a natural disaster when it occurs in a built environment. We cannot limit natural phenomena, so we must respect the earthquake, prevent it and reduce its consequences. This can be done by strengthening and making the structures we live in more resilient. Then we can have not only smart-green cities but also resilient cities.