After large-scale destruction in 11 provinces caused by earthquakes centered in Kahramanmaraş, "seismic isolators," which minimize the force that shakes buildings, came to the fore.
Explaining how the system works, its cost and its importance, civil engineer Ömer Faruk Şentürk said, "If there is a seismic isolator in a building, there are fewer chances of destruction but project work must be done properly."
An earthquake of magnitude of 7.7 occurred in Kahramanmaraş Pazarcık on Feb. 6 at 4:17 a.m. local time, followed by a 7.6 magnitude quake on the same day at 1:24 p.m. in Elbistan. Thousands of buildings were destroyed, and over 40,000 people lost their lives. While the debris removal works continue, initial findings show "seismic isolators" minimized the effects of earthquakes in some buildings and ensured their safety.
Şentürk, assistant general manager of a housing project in Istanbul's Başakşehir, said that the lateral acceleration due to the magnitude of an earthquake is often huge. The purpose of seismic isolators is to ensure that this acceleration has a minimum effect on the upper floors of a building.
We have now started using it in housing projects in Başakşehir and have seen its most important contribution in city hospitals in the earthquake-affected zone. However, seismic isolators in a building cannot fully assure its survival.
Explaining that there are different types of seismic isolators, Şentürk said, "You cannot buy and install them directly in a building. The design of the building or even the blocks must be made according to the isolator. Your architectural, static and electrical project should be on par."
As for the cost, Şentürk pointed out, "When you construct a building from scratch, it has an effect of 10%-15% on the total construction cost. But if you want to add isolators to the already constructed building, the cost increases two-three times."
Fusun Sümer, Assistant General Manager for Technical Affairs of a housing project (TMMOB) in Istanbul's Başakşehir district added, "A seismic isolator is a tool that reduces the effect of earthquake energy on the superstructure and protects the structure by providing controlled movement during an earthquake."
"With advanced technological devices placed at the foundation of the building, seismic isolators are convenient for structures that may still need to be evacuated within a short span of time, such as hospitals, fire departments, data centers, schools, bridges and viaducts," he noted.
"In order for the seismic isolators to be usable, other carrier elements of the structure must also be robust. All stages of design, implementation and inspection should be carried out meticulously. Project work of seismic isolation must be implemented properly and if the ground is weak, ground improvement works must be completed first. It is not enough to just build a raft foundation or rely on seismic isolation device for a structure to be built on very weak soil with the potential for liquefaction," Sümer said.
"Necessary ground improvement tasks must be carried out and the foundation of the building must be secured first. Seismic isolators prevent the transfer of energy to the concrete, allow the concrete to move in a controlled manner, and thus can prevent the loss of life and property during an earthquake. Another issue that should not be forgotten here is that the other carrier elements of the infrastructure must also be perfectly designed and manufactured," Sümer explained.
