'Like the spreading of a bucket full of sand...' Isias Hotel, Ebrar Sitesi, Rönesans... They became symbols of the earthquake

Sixty-four people, including all thirty-five members of two girls' volleyball teams from the TRNC, lost their lives at the Isias Hotel in Adıyaman.

"7 MONTHS OF WORK WITH A TEAM OF 25"

Prof. Dr. Ahmet Can Altunışık, a faculty member at Karadeniz Technical University (KTÜ) Faculty of Engineering, Department of Civil Engineering, and Director of the Earthquake and Structural Health Application and Research Center, stated that they have examined nearly 500 buildings where deaths occurred, commissioned by the Ministry of Environment, Urbanization and Climate Change, as part of the investigations conducted by chief public prosecutor's offices following the Kahramanmaraş-centered earthquakes on February 6, 2023, which affected 11 provinces.

"WE ARE TRYING TO FORM A GENERAL OPINION"

Altunışık stated that they have completed reports on some of the hundreds of case files they have been working on for about 7 months with a team of 25 people since they were assigned, and made the following assessment:

"One team can only handle one file in a week because sometimes dozens or hundreds of lives may have been lost in a collapsed building. There are sacks of data, papers, files, videos, minutes, and evidence. Working meticulously with a large team, we identify the parameters that caused the building to collapse if there is a culprit, and we address everything in detail, from the building's license date, occupancy permit, building inspection documents, soil and material properties, to its compliance with the regulations in force at the time the project was designed. In addition, we examine the files of those who inspected the building and prepared expert reports after it collapsed, and we try to form a general opinion."

"LIKE THE WAY SAND SPREADS"

Reminding that the expert reports for the Isias Hotel in Adıyaman and the Ebrar Sitesi in Kahramanmaraş were completed and submitted to the chief public prosecutor's office some time ago, Altunışık said, "The Isias Hotel was first designed and built as a residence. After the rough construction was finished, construction was paused for a while, and then it was converted into a hotel. However, the regulations changed during this period. The regulation the building was subject to at the date of its first license and the regulation it was subject to at the date it was converted into a hotel and its intended use changed are different. The building's projects were not checked according to the changed regulations. The core values at the Isias Hotel do not meet the regulations of the relevant date. The appearance of the hotel after it collapsed was like the way sand spreads after you turn over a bucket full of sand. You can see that the way the building collapsed is like the way sand spreads after you lift the bucket." he said.

THE REASON FOR THE COLLAPSE OF EBRAR SITESI

Regarding the report they prepared for Ebrar Sitesi, Altunışık said, "The damages observed in Ebrar Sitesi are unfortunately the same for all 20 blocks. There are significant deficiencies in the mechanical properties of the concrete and reinforcement during the manufacturing phase, as well as in reinforcement detailing such as stirrup spacing, cross-ties, and hooks. This is among the main reasons for the building's collapse." he stated.

APPLICATION PROBLEM

Explaining that they are also about to complete the file for the Rönesans Residence in Hatay, Altunışık noted the following:

"Since it is a very important building, we are trying to be very careful. It is a 3-block building. There are joints in both the foundation and the superstructure in its static project, and all 3 buildings have sustained damage from a distinct floor and have fallen or toppled backwards. All 3 blocks have the same damage mechanism. In our examinations, it is stated that there are some problems with the material properties and their application, but we want to make an evaluation between the pictures that come to us with the expert reports and express our clear opinion. I hope we will have submitted all our files to our chief public prosecutor's office before the first anniversary of the earthquake."

"14 MEGAPASCALS"

Emphasizing that they compared the data of the buildings destroyed in the Kahramanmaraş earthquake with the data of the buildings with 154 deaths destroyed in the 2011 Van earthquake, Altunışık said, "While the average core strength of the 154 buildings destroyed in the Van earthquake was 10.50 megapascals (MPa), the core strengths we obtained from nearly 500 buildings we examined that were destroyed in Kahramanmaraş vary between 10-14 MPa. These values show a slight increase after the introduction of building inspection, but unfortunately, the average values are currently a maximum of 14 MPa, and this is a low value." he said.

THOSE COMPLIANT WITH REGULATIONS ARE 50 PERCENT

Underlining that only 15 percent of the buildings destroyed in the Van earthquake had a soil survey report, Altunışık continued as follows:

"While we expected this rate to increase after about 15 years, unfortunately, this rate is around 19 percent in the Kahramanmaraş earthquakes. While 40 percent of the 154 buildings destroyed in the Van earthquake had a static project, this is around 50 percent in the buildings we examined in the Kahramanmaraş earthquakes. The compliance of buildings with static projects with the regulations made at the relevant date is again unfortunately around 50 percent. One of the most critical problems is the construction success of the relevant building. In the Van earthquake, the success rate in material properties such as concrete and reinforcement of the buildings and reinforcement detailing was 3 percent. We were expecting a much higher rate in the Kahramanmaraş earthquakes, but we are currently at the 11 percent level. Years are passing, we are improving ourselves and reaching a point, but it seems we have a long way to go. This is much more obvious, especially in structures built before a certain year. This picture is a harbinger that we need to urgently put certain structures of ours into urban transformation."

Wishing that such disasters would not be experienced again, Altunışık said, "Our country is located on an important earthquake belt; we may encounter such earthquakes in the future as we have in the past. For this reason, it is necessary to quickly examine our buildings of a certain age, and to strengthen or prepare those that are insufficient for urban transformation." he said.

News Source: 12punto