Gelisim News

‘’We can prefer not to build parking lots, banks, shops, galleries and stores on the ground floors!”

Istanbul Gelisim University organized an event titled "Damage and Causes of Collapse in Reinforced Concrete Structures Caused by Earthquakes". Assoc. Prof. Dr. Anıl Niş remarked that the fact that the ground floor and sometimes some of the upper floors of the buildings are car parks or shops with glass showcases caused their destruction.

Reasons such as weak column-strong beam, short column, cutting of columns, beam not connected to columns, lack of earthquake curtains in the structure, low concrete quality, flat and low strength of construction iron, absence of stirrups, rusting due to the use of sea sand cause heavy damage or destruction in the earthquake.

On February 6, an earthquake with a magnitude of 7.7, the epicenter of which was Pazarcık, Kahramanmaraş, caused disaster in 11 provinces. The scale of the disaster increased with the earthquake of 7.6 magnitude that occurred in the Ekinözü-Elbistan region just 9 hours after the first earthquake. In the event titled “Damage and Causes of Collapse in Reinforced Concrete Structures Caused by Earthquakes”, Assoc. Prof. Dr. Anıl Niiş stated that the examination of 1 million 188 buildings consisting of 4 million 371 thousand independent sections in earthquake zones was completed. Assoc. Prof. Dr. Anıl Niş from Istanbul Gelisim University (IGU) Faculty of Engineering and Architecture, Department of Civil Engineering, was informed by the Ministry of Environment, Urbanization and Climate Change about 156 thousand buildings consisting of 507 thousand independent sections were demolished, will be demolished immediately and damaged.

“Light structures begin to move laterally, while heavy structures begin to hit into the ground”

Poor ground conditions are the leading causes of damage and collapse due to earthquakes. When the structures are examined, it is seen that the earthquake damage is mostly the structures built on fertile agricultural lands. Assoc. Prof. Dr. Anıl Niş: “After the examinations, the structures with multi-storey and flexible carrier system on weak soils at risk of liquefaction were damaged. During the earthquake, ground became fluid like a liquid. Light structures begin to move laterally, and heavy structures begin to hit the ground. This caused serious damage to the structures. This showed that adequate measures were not taken on the ground or the necessary ground tests were not carried out during the construction of the structures.”

“Approximately 70 percent of the horizontal displacement caused by earthquake occurs in the soft storey”

In general, the ground floor and sometimes some of the upper floors of the buildings are built as parking lots, galleries, banks or shops with glass showcases. Other floors are built with infill walls. This is a common practice for commercial reasons.

Assoc. Prof. Dr. Anıl Niş: “Floors with infilled walls are much stronger in earthquakes than floors without walls or with glass showcases. Floors without walls or with glass showcases are powerless. This soft floor irregularity has emerged both in new constructions and after the conversion of old residences into workplaces for commercial reasons. Moreover, the fact that the height of one floor is higher than the other floor causes soft floor irregularity. This is the main reason for the collapse of multi-storey structures with soft storey irregularities in the 1999 Gölcük earthquake and the 2023 Kahramanmaraş earthquake. Soft storey formation must be prevented. The load-bearing system should not only consist of columns, and the earthquake force must be met by shear walls by giving weight to the curtain carrier.

Assoc. Prof. Dr. Anıl Niş, who also warned against a possible Marmara Earthquake, added that houses must be inspected at certain periods, similar to the inspection of vehicles. Especially in multi-storey buildings, the renovations made by the site management must be examined very seriously. Some homeowners and shop owners may intentionally or unintentionally damage the structural system of the building during the renovation. The carrier system such as columns, curtains, beams should never be lifted.