Notes prepared for the TRT Radio-1 Günebakan Program broadcast live.
Translated from Turkish. The notes cover potential topics. Although the purpose of the talk is similar, the audio content may differ since I did not read the notes verbatim. May 30, 2024
1. Can you introduce yourself?
My name is Kurtuluş Atasever. I completed my PhD in earthquake engineering and worked as a visiting researcher in Tokyo with the supervisors of Prof. dr. Oğuz Cem Çelik and Prof. Dr. Toru Takeuchi, I conducted experimental studies and developed self-centering seismic dampers. Our aim was to ensure that buildings could continue to operate without any damage after a major earthquake. Currently, I am an academician at Mimar Sinan Fine Arts University, Department of Architecture, Structural Engineering, and also the founder of Binamod.
2. Can you provide details about the development of Binamod, the services offered, and their implementation?
As you know, earthquakes periodically come into the public spotlight, but their effects are quickly forgotten. This is understandable because the problem is so vast that most people feel there is nothing more to do than talk about it. For instance, in Istanbul alone, over half a million buildings need to be inspected and their earthquake performance likely improved, a task that could take decades just to collect the necessary data.
Binamod was designed as a comprehensive solution, knowing that addressing the earthquake issue will take a very long time. With support from TÜBİTAK, we developed a mobile application that collects information from buildings step by step and provides users with earthquake-related information at each step.
The main purpose of the application is to prepare users for an earthquake. With the new update to be released next month, users will be able to request information about the earthquake performance of their workplace, their child's school, or the hotel they plan to stay in.
Additionally, users will be able to receive earthquake notifications about the buildings of their family and friends and send post-earthquake damage assessment requests. We notify users of an earthquake and ask if they are okay if their building is likely to be damaged, and we send their responses to their friends.
We will be releasing the second version of the application next week.
To date, nearly 10,000 individual users have registered on the application, and we are sending earthquake notifications to them. We have provided building risk prioritization services for approximately 500 individual users.
Furthermore, we have provided risk prioritization and comprehensive data collection services for corporate companies for over 100 buildings across Turkey. Our efforts have contributed to reducing the life safety risk for nearly 5,000 people so far.
By standardizing the data collection system with the mobile application, we aim to make buildings with good earthquake performance visible. We want to make the earthquake performance a real estate valuation criterion.
3. What information do you collect about buildings?
The first data we collect is the building location, which helps present the user with information about the earthquake hazard in the region, past earthquakes, nearby faults, and casualties.
In the next stage, we request building photos, age, and the number of floors. This allows us to calculate structural irregularities and expected ground motion acceleration, and determine how urgently the building should be examined by comparing it with buildings in our database.
Subsequently, an expert obtains geometric properties and material information from the critical floor of the building, allowing us to determine an approximate earthquake performance.
In the final stage, geometric, floor, and material properties are obtained for the entire building.
As the level of information increases, the accuracy of the result also increases.
We also systematically and quickly store the data we collect using 3D photography and lidar for future use.
4. How is earthquake risk prioritization done?
Earthquake risk prioritization is crucial for our country.
From a public perspective, it is not feasible to simultaneously strengthen all buildings that do not comply with current regulations due to time and economic constraints.
In the private sector, companies with hundreds of branches must spread these operations over several years when deciding about relocations and purchases.
The main purpose of risk prioritization is this:
First, it aims to identify buildings that will ensure life safety during an earthquake. Identifying these buildings is easier than finding ones that are in good condition. For instance, poor-quality concrete can be detected visually, but tests are required to confirm good quality. Thus, the most at-risk buildings are identified through rapid assessment methods without needing data for the entire building.
These buildings require urgent intervention. Other buildings are then ranked according to the expected earthquake in their location and their capacity to withstand it. Actions to be taken are determined based on this ranking.
5. How is earthquake damage assessed?
The main purpose of damage assessment is to evaluate whether the earthquake has reduced the performance of your building compared to its pre-earthquake state.
In a slightly damaged building, the earthquake performance is close to what it was before the event. This means the earthquake has not significantly affected your building's performance.
To clarify, the performance of your building a week before the earthquake should be similar to its performance today if only minor damage has occurred.
The critical point here is that damage assessment only reveals how much performance the building lost during the earthquake. Even if your building is slightly damaged or undamaged, it does not provide precise information about the expected performance in the next earthquake. Comprehensive analyses are required for that.
If a building is severely damaged, it has largely lost its pre-earthquake capacity, and it is often recommended to rebuild it.
Although damage assessment may seem straightforward, it involves an academic background. Earthquake damage is determined by examining the crack widths in structural elements. The methods used globally and in our country are similar.
Based on the crack width, the damage level of the structural element is determined. For instance, hairline cracks are not very significant, but spalling in concrete indicates a reduction in the element's load-bearing capacity. The building's damage status is assessed by examining the type and number of damaged elements.
Another critical issue in damage detection is the panic caused by relatively minor damage to non-structural elements. After the Kahramanmaraş earthquakes, an undamaged site's non-load-bearing wall was mistaken for a structural wall, leading to an evacuation and a need for temporary shelter for more than 2000 people. During the 2019 Marmara earthquake, we encountered damage in many buildings not caused by the earthquake but by corrosion. This is common, especially in minor earthquakes.
We included a module for this in the Binamod application. By detecting non-structural damage through photographs, we aim to reduce panic and the need for temporary shelter. Currently, this is being examined by experts, and we are working on integrating it into the artificial intelligence module.
6. How is seismic retrofitting done?
Seismic retrofitting means increasing the earthquake performance of buildings. For ordinary buildings, we expect them to be damaged but not result in loss of life. In other words, without special design, new buildings are expected to sustain damage during an earthquake, but loss of life is unacceptable. Therefore, there are several main approaches to retrofit.
The first is to increase the damage capacity of the building. We aim to prevent the building from collapsing, even though it will sustain damage and absorb energy from the earthquake. To achieve this, columns and beams are wrapped to enhance their energy absorption capacity. Increasing the building's damage capacity is the most crucial aspect.
Secondly, we can increase the building's strength by enlarging existing elements or adding new shear walls. This approach aims to minimize displacement during an earthquake.
Thirdly, our focus as academics and a company is on reducing the earthquake forces acting on the building. This involves using seismic isolation and/or dampers to reduce the forces on existing structural elements.
Seismic retrofitting is typically achieved using a combination of these methods.
7. How do you develop disaster management scenarios?
With the new version of the Binamod application, users will be able to add their family members or friends.
We have developed an algorithm that asks users if they are okay after an earthquake and forwards their responses to their friends, facilitating quick communication after the event.
This service is also designed to allow employees of large institutions to quickly report their status after an earthquake.
Additionally, we offer users the ability to quickly detect damage after an earthquake, reducing panic and ensuring they can return home immediately if there are no issues.
Our primary focus is on reducing risk.
Disaster management is not feasible for a user living, working, or attending school in a building that does not ensure life safety during an earthquake. Therefore, the first step is to improve the building.
In the next phase, we send notifications to continuously remind users about earthquake preparedness. We are also working on determining meeting points after an earthquake, obtaining housing/natural disaster insurance, and preparing a disaster kit through the application.
8. If you had the opportunity to observe the earthquake area after Kahramanmaras Earthquakes (February 6), could you briefly share your evaluations on this subject?
We visited the field from February 9th with Prof. Dr. Alper İlki and a large technical team. We primarily examined public buildings. Together with international teams, mostly from Japan, we compared Turkish and Japanese damage assessment methods. We had the opportunity to see most of the affected region. There is little new to report on a building-by-building basis; the findings are quite similar to those in the reports written after the 1999 earthquakes.
Our focus was on collecting damage data and testing our methods. In our study of over 17,000 buildings, we found that if proper prioritization is done, one unit of expenditure to ensure life safety before an earthquake provides 6-7 units of benefit after the earthquake. Considering the damages are in the billion-dollar range, the potential benefits are significant.
9. What are your suggestions regarding the expected earthquake in Marmara?
The problem in Istanbul is quite significant. I visited a building that was heavily damaged in the 2019 Earthquake off the coast of Silivri. The building was 50 km from the epicenter and should not have been damaged because the accelerations were quite low. Yet, it was heavily damaged, indicating that there are buildings in Istanbul that are barely standing, let alone ready for an earthquake.
From a public perspective, my suggestion is that all pre-2000 buildings should be rapidly scanned and risk-prioritized. If we classify buildings from A (good) to E (bad), the goal should be to ensure that there are no buildings left in Class E within the first 10 years. The most severe losses of life and financial losses occur in the riskiest buildings. Current regulations aim to ensure excellent building performance, but there is not much time and perhaps no need to immediately upgrade all very bad buildings to very good. However, it is clear that gradual improvement is necessary.
From a private sector perspective, we are trying to address this with Binamod. The earthquake performance of buildings is not simply black or white. Two new buildings constructed today may have different earthquake performances. Ideally, everyone would want to live in homes that would not be damaged in an earthquake and have their children study in such buildings. This is technically possible in Türkiye today, and there are institutions that prioritize this issue.
Our aim is to identify residences, schools, and companies with good earthquake performance. We want to ensure that individual users prefer institutions that invest in earthquake safety when choosing where they live, work, and study. In the long term, making good buildings visible will lead to broader solutions.
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