Wrong analysis project (URGENT)

[kastos]

Hello everyone, There was a model in the program that we could not solve the relative floor drift. I realized that I did not specify the stair support conditions while making this model. Later, I used the fixed support option while bracing. When I did this, the program deleted the relative floor error and found the project too rigid. 4/5 R should be applied error. In a 6 flats (2 duplex) residence, can fixing the ladder with a fixed floor solve the relative floor drift that I couldn't solve even though I used 5 curtains? How much can I trust this project? In the earthquake report, the relative floor values dropped to almost 0. If the same calculation was made in the previous projects that we solved with a fixed support, who will take responsibility for this? In addition, the thickness of the foundation in the project is now 30 cm. When I want to make the foundation 40 or 50 cm, I get the error that the reinforcement is insufficient. Could it be such nonsense? Do I have to make the foundation 30 cm? Basically, even if you use 32 iron, I get the error of insufficient reinforcement. In fact, I made 50-60 cm, and the reinforcement spacing had decreased to 7 cm. Dear colleagues, this is my first post. I hope I didn't violate forum rules. Thanks in advance. :roll:

 

[HakanŞahin]

Hello, Defining all stair supports as fixed is not a correct data entry according to the real situation. The superstructure is interactive, and you fix all the movement of the structure that you have solved with the ladder to the existing ladder in the core. As a matter of fact, if you examine the deformation of your structure, you can see this behavior. Correct data entry is to remove the fixed support on all sides, connect to the elements that should have a ladder, and then move on to the analysis. (If you want to solve all the edges of the staircase with fixed support, you have the option to solve the staircase independent of the structure.) In order to provide relative floor offsets, you need to increase the system stiffness [/u] in the y direction. Rather than the number of curtains, it seems important to create the placement of the curtains in the appropriate direction to contribute to the structure. If you change the thickness of the foundation, the change in the raft calculation may also depend on the staircase issue I mentioned above and the superstructure interactive solution. First of all, it is necessary to design the mathematical model as it is applied on site and to give it to the program, and it is the responsibility of the designer to ensure this. Good work

 

[kastos]

A solution without superstructure interaction cannot be made because our floor class is ZD. I am waiting for messages if anyone can solve the relative floor offset in this project without using a fixed support for the ladder. The elevator shaft and the staircase are already visible in the project. I can also send the architectural project to those who want it.

 

[Ismail Hakki Besler]

Fixing the brackets is wrong. When you fix it, you prevent not only the ladder but also the structure from making displacement by fixing it at those points. Whoever enters the messages permanently, that person will take the responsibility. The subject title of the project, for which the wrong analysis was made, does not match the explanations you gave. The program performs the analysis correctly according to the situation you modeled incorrectly. If the displacements did not shrink even though you were using a fixed support, then it would make sense to let us know why they are not shrinking. I've moved your post to a more popular thread so that more people can see it.

 

[miralay]

Mr. İsmail, I did not understand the purpose of this option if using a fixed support for the solution together with the structure on the stairs also supports the structure on the relevant side. In that case, even if it is a single-storey building, I think it would be correct to accept the staircase as a fixed support only on the floor where the foundation is not entered. I'm sorry if I misinterpreted it. Can you explain where this option should be used on the ladder?

 

[2m proje]

Ismail Bey, I did not understand the purpose of this option if using a fixed support for the solution together with the structure on the stairs, supports the structure on the relevant side as well. Therefore, even if it is a single-storey building, the staircase can only be accepted as a fixed support on the floor where the foundation is not entered. Sorry if I misinterpreted it. Can you explain where this option should be used on the staircase?

Hello; In some cases, the staircase may be connected to another structure or foundation that we cannot model outside of the structure, in this case, while solving the staircase together with the structure, some edges should be fixed on the support. This is an option that should be used carefully, for example, if you are making a basic interactive solution for the building, you can hang the entire structure on this staircase. Or, as in the project we talked about, the stairs may be blocking the displacements of the entire structure. For stairs that are completely within our structure, this option is only available in the basic non-interactive solution. It should be used for the edge of the stairs that step on the foundation. Best regards. Sent via iPhone using Tapatalk

 

[Ismail Hakki Besler]

Ismail Bey, I don't understand the purpose of this option if using a fixed support for the solution together with the structure on the stairs, supports the structure on the relevant side. In that case, even if it is a single-storey building, the staircase can only be accepted as a fixed support on the floor where the foundation is not entered. Can you explain where this option should be used on the stairs?

It should only be used when sitting on the ground at the bottom floor.