Story Drift Example
![](../__attachments/1097367720/12.png?inst-v=f19fc7cc-758e-4997-b5f0-444a3286777e)
Let's determine the effective relative storey drifts obtained in the earthquake loading of a 3-storey building with a beam slab system consisting of a reinforced concrete moment transfer frame with a span of 2 * 4 m in the Y direction and a span of 2 * 6 + 8 m in the X direction, and let's compare it with the limit value. .
Solution:
First of all, it is necessary to determine the column with the highest horizontal displacement in EX loading at each floor. For this, perspective screen - view analysis model - deformations - EX loading is selected. The X direction displacement of the top joint of the columns at each level is read.
![](../__attachments/1097367720/13.png?inst-v=f19fc7cc-758e-4997-b5f0-444a3286777e)
For the determination of the relative translation, it is necessary to read the displacements that will give the greatest difference. The readings made in the other floors are as follows:
![](../__attachments/1097367720/ab.png?inst-v=f19fc7cc-758e-4997-b5f0-444a3286777e)
![](../__attachments/1097367720/abc.png?inst-v=f19fc7cc-758e-4997-b5f0-444a3286777e)
The values read are the raw values as a result of the analysis. It should be increased in accordance with TBDY 2018 4.8.4 according to the equivalent base shear force enlargement coefficient.
![](../__attachments/1097367720/abcde.png?inst-v=f19fc7cc-758e-4997-b5f0-444a3286777e)
The equivalent base shear force amplification coefficient given for the X direction in the dynamic analysis report was determined as 1.22. The raw values read on the perspective screen need to be incremented by 1.22. According to this;
(9.64*1.22)-(6.22*1.22)=4.17
![](../__attachments/1097367720/abcd.png?inst-v=f19fc7cc-758e-4997-b5f0-444a3286777e)