Farklı zemin kat yüksekliklerinin yapı performansına etkisi

Abstract

Genel olarak yapıların zemin kat yükseklikleri ticari amaçlardan dolayı normal katlara nazaran daha yüksek bir şekilde inşa edilmektedir. Bu çalışmada örnek olarak seçilen bir betonarme yapı için zemin kat yüksekliğinin değişiminin yapı performansına etkisi incelenmiştir. Bu çalışmada örnek olarak seçilen betonarme bina için zemin kat yüksekliği 4m, 5m ve 6m seçilmiş ve bu değerlere göre yapının performans hesaplaması yapılmıştır. Elde edilen sonuçlar karşılaştırılarak öneriler yapılmıştır. Zemin kat yüksekliği arttıkça meydana gelen tepe yer değiştirme talepleri artmış ancak yapı taban kesme kuvveti azalmıştır. Analizlerden elde edilen yapı çökme mekanizmaları, depremde yumuşak kattan dolayı oluşan gerçekçi çökme mekanizmaları ile benzeşmektedir. Depreme dayanıklı yapı tasarımı dikkate alınarak mümkün olduğu kadar eşit kat yüksekliği seçilmelidir. Bu çalışmada yumuşak kat oluşumuna sebebiyet veren faktörlerden biri olan zemin kat yüksekliğinin etkisi dikkate alınmıştır.

Keywords

• Yumuşak kat, kat yüksekliği, statik itme, betonarme, zayıf kat, deprem

Effect of Different Ground Floor Height to RC Buildings Performance

Abstract

The importance of studies, researches and prevention about earthquakes have risen after destructive earthquakes in the world recently. The damages of earthquakes increase through vulnerability of urban and rural building stocks. The size of earthquakes and the negative structural features increase the damage amount. To know the properties of buildings to be negatively affected the seismic behavior of buildings under earthquakes are put forward to ensure more serious approaches to reduce the level of damage risk after earthquakes. In order to reduce the damages of the earthquakes, the performance of buildings needs to be determined at first. The earthquake safety of existing buildings has gained considerable importance after earthquakes occurred in our country especially in the last 30 years. Performance based assessment methods have been widely used for existing reinforced concrete structures. The height of the ground floor of the building has been constructed higher than normal levels for commercial purposes. In this study, the effect of changing ground floor height to performance of RC building was investigated. In this study, the ground floor height of RC building was selected such as 4m, 5m and 6m and performance calculations were made for these values. The selected reinforced concrete frame building has four stories and each of normal story height is 3m. The material used in the structure is C30-S420. The reinforcements used in the beams and columns were selected as 16. Columns were selected as 30*50cm, and beams were selected as 25*50cm. The transverse reinforcements (stirrups) used in both elements were selected as 10/10. Maximum displacement values and deformation statuses calculated for the X and Y directions for each different ground floor height. Static pushover analysis curves for X and Y directions for different ground floor height were obtained and compared. Changing the height of the ground floor was increased the peak displacement value but structure base shear value was decreased. The resulting values are compatible with the collapse mechanism caused by soft floor. The size of earthquakes and the negative structural features have caused an increase in damage extent. Knowing the properties of buildings that have negatively effect to the seismic behaviour of buildings under earthquakes will be put forward to ensure more serious approaches to reduce the level of damage risk after earthquakes. Most of the damaged buildings have not been constructed according to national earthquake codes. Knowing the reasons of earthquakes damage is important to minimize the probable economic and life loses. Recently modern disaster management emphasized not only disaster preparedness but also the importance of disaster prevention. Negating buildings' earthquake vulnerability means to render them more durable in the case of a possible earthquake. In this context, the importance of building designers' compliance with the provisions of the regulations concerning building design gains prominence. In addition, after the design phase it is essential to conduct the required and adequate controls during the actual construction of buildings. In order to ensure that a project gains both technical and scientific significance, the sensitivity shown during the construction phase should be maintained throughout the whole process of the project. Weak/soft storey formation should be avoided, earthquake forces should be carried by partitions and frequent stirrups should be used in each section of columns of the floors demonstrating such negative property.

Keywords

• Soft story, weak story, floor height, earthquake, pushover curve, RC building