ELAZIG GUNISIGI NEWSPAPER - January 2011
CAN BUILDINGS STAY UP WITH THE HELP OF A CRANE?
Unfortunately, there isn’t a day in our country when an issue related to buildings doesn’t arise. On Friday, January 29, in Bayrampaşa, Istanbul, excavation work for the foundation of a new construction caused damage to the neighboring building. The municipality declared it uninhabitable, and five families were left out in the cold during the winter.
In the Cevatpaşa neighborhood on Mehmet Akif Street in Bayrampaşa, the excavation for the foundation of a new building had been completed. Around midnight, residents of the neighboring building, who felt the tremors, panicked, thinking it was an earthquake. All the residents rushed out of the building, but it was soon realized that the shaking was not due to an earthquake but was caused by the settling of the foundation of the new building.
When the municipal teams arrived the next morning, they declared the building uninhabitable, leading to the residents' suffering. They were victims before an actual earthquake even occurred. God forbid, if an earthquake were to strike anywhere in our country, I can't even imagine what the consequences would be for us.
The residents have tried to find a solution to the issue on their own. They managed to provide support to the tilting building with the help of a crane. Considering that even a small 4-5 story building weighs hundreds of tons, the support of a 5-10 ton crane clearly cannot provide much help. Furthermore, it’s evident that supporting the building from a single point will not significantly contribute to keeping the building standing.
Attempting to keep the building upright with a crane is a clear indication of the state of our current building stock. The building that appears to be standing thanks to a crane is just the visible face of the situation. The behind-the-scenes reality is the lives of people living in homes that are barely holding on.
The truth is, precautions could have been taken to prevent this situation during the excavation process. However, many buildings in our country have foundations that are either non-existent, only nominally "foundations" with no practical function, or shallow foundations. This situation will lead to severe damage in the event of a potential earthquake.
Buildings in a row are one of the basic structural problems in our country. While there is no rule stating that buildings cannot be constructed in a row, there are numerous regulations that must be followed for such construction (although perhaps some may think they can bypass these). The event in Istanbul is just a small example. If you wish to build a building with a basement next to one without a basement, you are facing a serious problem. This can be explained as follows: If an excavation deeper than the existing foundation is to be done next to an existing structure, additional precautions must be taken. The danger increases depending on the soil classification. If you consider the reclaimed lands where urban centers are built, the situation becomes clearer.
Liquefaction of the soil and the hammering effect are the most significant risks for buildings in a row during an earthquake. If a building lacks adequate depth (basement + foundation), and if the groundwater level is high and the soil’s bearing capacity is insufficient, the building may collapse or sink during an earthquake. If liquefaction does not occur, two buildings may collide due to oscillation.
Buildings that collide with each other suffer damage or collapse due to the damage to their structural elements. Therefore, when constructing buildings in a row, the floor levels of the buildings should be the same. If attention is not paid to details such as this, even buildings that comply with all the rules in their design and construction may sustain damage or even collapse.
There are thousands of buildings in our city in similar situations. The collective solution to this risk lies in urban transformation. The renovation of buildings in city centers will gradually reduce structural risks over time.
FOR ELAZIG...
The buildings to be constructed in Elazığ are of great importance for the city’s structural vision. To prevent the types of problems seen in Istanbul from happening here, precautions must be taken in advance. As you know, there is an important project whose competition has been completed, and I expect it to be implemented soon. I’m referring to the business center that will be built in place of the İl Özel İdare Lodgings on Vali Fahri Bey Street.
There are neighboring buildings near the excavation of this business center as well. The 8-story neighboring building having a basement is an advantage for the excavation, but the weight of the building poses a significant risk. The other neighboring building, being older and having a shallow foundation, is a serious problem. Therefore, I recommend that these risks be considered during construction.
I know from the project plans that the business center has a significant foundation depth. For this reason, I wanted to fulfill our duty of expressing these concerns in advance.