ELAZIĞ GÜNIŞIĞI GAZETESİ - May 2010
EARTHQUAKE-RESISTANT BUILDING EFFORTS OF MUNICIPALITIES
Earthquakes are one of the undeniable issues in Turkey, which we emphasize at every opportunity. Over the past years, many destructive earthquakes have occurred, causing significant loss of life and property. Following these earthquakes, two major problems have emerged: the design and construction of earthquake-resistant buildings, and the strengthening of the existing building stock against earthquakes. If newly constructed buildings are not designed to be earthquake-resistant, the stock of buildings that need to be reinforced will continue to grow each day. Therefore, buildings should be designed and constructed in compliance with the 2007 Earthquake Regulation. High-quality production is possible with continuous monitoring. To achieve earthquake-resistant buildings, the design and construction processes must be kept under control. In Turkey, these tasks fall under the responsibility of various official institutions and organizations.
It has been observed that the regulations set forth in earthquake regulations that have been in effect until now have not been fully implemented, both during the design (planning) phase and the construction phase. The primary methods for enforcing these regulations can be considered as educational seminars and inspections. If buildings are designed based on their characteristics rather than strictly following the regulations during earthquake forces, the importance and necessity of an effective control system becomes even more apparent.
Municipalities are one of the institutions that bear a significant responsibility in construction-related matters. Municipalities are responsible and authorized at every level, from land preparation to the issuance of occupancy permits. Given that our country must live with the reality of earthquakes, this responsibility becomes increasingly crucial. Based on this important task of municipalities, a survey was conducted in 2007 to assess their approach and behavior regarding earthquake-resistant building design and construction, and to ensure the exchange of information between municipalities. The findings of this survey were shared at the International Earthquake Symposium held in Sakarya between October 1-3, 2009. It is hoped that the results of this survey will positively influence and improve Turkey’s plans and programs related to earthquake-resistant building design and construction. The survey results have also been shared with the public in Elazığ through our newspaper.
Below are the general questions from the survey regarding the efforts of municipalities in ensuring the quality of construction:
- Approximately how many people live within the service boundaries of your municipality?
- How many construction permits did your municipality issue in 2005?
- How many construction permits did your municipality issue in 2006?
- How many civil engineers work in your municipality’s Zoning Department?
- How many architects work in your municipality’s Zoning Department?
- How many geologists work in your municipality’s Zoning Department?
- How many private concrete plants are there within the borders of your municipality?
- Does your municipality have its own concrete plant?
- Is ready-mix concrete usage mandatory in construction projects within your municipality?
- Are concrete pours in construction projects monitored by your municipality on-site?
- Are the steel reinforcement arrangements in construction projects checked for compliance with the project by your municipality on-site?
- Does your municipality have a construction inspection laboratory?
- Does your 2007 work plan include the establishment of a construction inspection laboratory?
- Can concrete compressive strength and cutting tests be performed in the laboratory?
- Can aggregate (sand-gravel) tests be conducted in the laboratory?
- Can cement-related tests be conducted in the laboratory?
- Has your municipality organized vocational training seminars for construction workers and foremen?
In the six-month survey process, efforts were made to reach municipal authorities through fax, mail, and email. The participation of 59 provinces in the survey was achieved nationwide. When evaluating the survey results, only the responses from provincial municipalities were considered, as construction work in metropolitan areas is handled by district municipalities. Considering all 81 provinces, 31,333,845 people live in the 1st and 2nd-degree earthquake zones, 6,466,436 people in the 3rd and 4th-degree earthquake zones, and 139,912 people in the 5th-degree earthquake zone. That means 83% of the population lives in the 1st-degree earthquake zone. When the population of villages is included in this comparison, this percentage rises to nearly 90%. These statistics clearly reveal the extent of the earthquake threat in Turkey. Considering that migration from rural areas to cities is constantly increasing, the enormous burden and responsibility of provincial municipalities becomes evident. This magnitude is also reflected in the construction permits granted. The municipalities participating in the survey serve a population of over 20,153,957 people. These municipalities issued a total of 11,346 construction permits in 2005 and 12,706 permits in 2006. "If the ever-growing building stock is not kept under control, the earthquake threat will continue to increase."
In earthquake-resistant building production and building inspections, the most important factor is the people involved. The engineers responsible for achieving the goal are key. When thinking about earthquake-resistant buildings, construction engineers immediately come to mind. These technical personnel, who prepare, implement, and inspect building projects according to standards and regulations, must be sufficiently present in municipalities to ensure proper inspection. In four provinces located in the 1st and 2nd-degree earthquake zones where no construction engineers are employed, a total of 401 permits were issued in 2005 and 464 permits were issued in 2006. These provinces, where no construction engineers work, are not part of the pilot municipalities within the scope of the Building Inspection Law. This concerning result indicates that it is impossible to ensure proper inspection with only one or a few construction engineers in cities where hundreds of homes are built each year in earthquake zones.
As a result of the painful experiences from recent destructive earthquakes, it has been understood that architects and geological engineers also make significant contributions to earthquake-resistant building production. Especially during the design phase, it is crucial that the plan prepared by the architect complies with the fundamental rules of earthquake-resistant buildings. According to the survey, 9 municipalities in the 1st and 2nd-degree earthquake zones do not employ architects. One of Turkey's major issues is unplanned urbanization. The conversion of agricultural lands into building plots has greatly harmed agriculture, and buildings constructed on unsuitable lands have suffered severe damage during earthquakes. The importance of the soil’s condition against earthquake forces is clearly seen in buildings that sink or topple, despite not suffering structural damage. Geology engineers, who are experts in this critical parameter, must be actively involved in zoning and construction works. It was found that 14 municipalities in the 1st and 2nd-degree earthquake zones do not employ geologists.
There are three provinces in Turkey that still do not have ready-mix concrete plants, and these municipalities do not have their own concrete plants either. Considering the problems experienced even in ready-mix concrete pours, the quality of on-site poured concrete is likely to be far below the standards. Unfortunately, this contributes to the increase in the number of buildings with inadequate earthquake resistance.
It is a positive development that 17% of municipalities have their own concrete plant, which plays a crucial role in producing quality concrete and preventing unfair competition in the market. In almost all provinces, at least one ready-mix concrete company operates. If all these concrete plants are inspected and produce in compliance with standards, positive developments in concrete quality can be expected.
Ready-mix concrete minimizes errors compared to on-site poured concrete. The municipalities' requirement for ready-mix concrete varies in different regions: it is mandatory in certain cases, partially mandatory for buildings above a certain height (such as buildings with more than five floors), and voluntary in others. This rule is somewhat controversial for city centers.
One of the fundamental principles of earthquake-resistant building construction is to carry out manufacturing in accordance with the project. Therefore, the dimensions, placement, number, and diameter of reinforcement elements must be checked. It appears that municipalities pay attention to this issue. However, without enough construction engineers, it is concerning how effectively the inspection of rebar in hundreds of buildings can be done.
To determine the properties of concrete samples and other materials in construction, a laboratory with testing capabilities is required. It is noteworthy that only four provinces in 1st and 2nd-degree earthquake zones have such laboratories. All laboratories can conduct tests related to concrete and aggregate, but only two can perform cement-related tests.
The destructive earthquakes in our country have exposed many shortcomings in building design and construction. One of the most important of these shortcomings is projects that do not comply with standards and regulations. Thanks to the use of software programs by architects and engineers in recent years, the issue of project-regulation mismatch has been largely resolved. However, it is much more difficult to address project-execution mismatches. To solve this issue and address difficulties in implementation, organizing training seminars and courses for construction workers and foremen would be highly beneficial. Moreover, workers without certification should not be employed in construction projects. In short, the knowledge of all technical personnel involved in producing earthquake-resistant buildings must be continuously updated.
Turkey, as an earthquake-prone country, should develop a qualified program with all relevant institutions and organizations, continuously updating and monitoring it. The results of the survey will have a significant impact on the country's earthquake strategy. The results of the survey can be summarized as follows:
- It has been determined that municipal authorities in Turkey do not have sufficient technical personnel for the inspection of earthquake-resistant buildings.
- The inability to reach about 25% of the municipalities for the survey indicates weak communication between institutions. This should be addressed, and a data pool should be created for all earthquake-related institutions.
- If the quality of concrete and the characteristics of reinforcement do not meet project standards, the number of buildings with inadequate earthquake resistance will continue to rise. As a result, preventing earthquake damage will not be possible.
- As the quality of buildings increases, their lifespan and economic lifespan will also increase.
- Approximately half of Turkey’s population lives in cities. Even though building inspections face many problems in urban centers, it is evident how prepared we are for earthquakes when considering the buildings in districts, towns, and villages.
- Municipalities have significant responsibilities regarding earthquake preparedness that cannot be ignored. Therefore, the deficiencies in the Building Inspection Law should be addressed as soon as possible with all relevant institutions, and it should be implemented nationwide. The role, importance, and duties of municipalities should be clearly defined in this law.
In general, the results of the survey reveal that, despite Turkey’s location on an active earthquake belt, the necessary sensitivity has not yet been fully shown. To prevent the increase in buildings with inadequate earthquake resistance, municipalities should be relieved of some of their responsibilities, coordination between municipalities should be improved, and common strategies should be developed and implemented. Reducing earthquake damage will not be possible unless residential buildings are constructed with high earthquake resistance.