a number of topics

[teknikisler]

I would like to thank in advance those who will review my attached posts and write answers about the issues that we discussed with my colleagues and building inspectors and the questions that come to my mind.

 

[cakilomer]

Hello, your questions are usually in my head, to benefit from the experience of our esteemed brothers and to expand the subject, I answered as an inexperienced engineer, I hope more detailed sharing will come of what I know. Let me add to what you said about hollow blocks, you said that hollow floor tiles are considered normal ductile and you said that it cannot be made as a frame without curtains, and the last In your question, you said that the frame is normal ductile when we add a high ductile curtain (R=7?), how did you come to this conclusion? Also, at a point I don't understand, when we get R=7, do all the curtains we put in the system have a high ductility level (even if R = 7 after B1 irregularity and alpha s controls) Let me ask you a few questions? 1. In the investigation of the relative storey drift, if there is a heavy exterior facade in our building, these calculations reveal great differences. Is it possible for us to calculate this or to enter this exterior into the program? 2) I know that choosing a mixed system is generally suitable for high floors, do you think this is true or what is the truth? thanks.

 

[NYILMAZ]

Friends, if you are writing a comment, topic, etc. "I think", please do not write to the file and send it. I request you to write directly to the forum for ease of reading. It can be a technical file (pdf or something), a picture, a project file, then it can be an attachment. But it is more useful if other explanations are displayed as they are in the forum. Besides, I think that it would be easier to answer by making quotations in some parts of the article in this way.

 

[teknikisler]

I couldn't add it before. I guess it was because of the word writing technique, I just added it now. I wanted to write my questions and thoughts on a number of issues that stuck in my head, thank you to those who have information about the subject or those who want to share their opinions. IN REINFORCED CONCRETE BUILDINGS WITH I=1 BUILDING SIGNIFICANCE COEFFICIENT 1-Is it the most appropriate solution to choose semi-rigid diaphragm method as the analysis method in structural analysis? 2-The surroundings or some edges of the elevators are generally designed as curtains. The general purpose of this is; Since elevators generally correspond to the center of the building, I think it is to create a curtain core for the carrier system. But if we do not want to make curtains in the building, is there any harm in designing elevator shafts as frames? 3-I heard that elevators do not transfer loads to the carrier system, but transfer loads directly to the foundation. I couldn't find any resources on this anywhere. If anyone has knowledge on the subject, can they give information about how much load the elevators will transfer to the system (walls, columns or beams)? 4- Regarding rigid basements, for example, if only 2 sides of a 12*14 meter building are under the ground, if 2 sides are surrounded by a curtain (ie 12 meters in the X direction and 14 meters in the Y direction), do you think this floor will be considered a rigid basement floor. Should it be accepted? 5-Could you give some information about whether the following inferences I made from the regulation on the selection of ductility and R coefficient are correct? a- Since hollow blocks and beamless slabs are accepted as normal ductile, they cannot be constructed as a frame without shear in 1st and 2nd degree earthquake zones. b-1. and 2nd degree earthquake zones, if it is desired to use a hollow floor or beamless slab system, reinforced concrete shears that continue along the height of the building must be made. In these cases, the ductility level can be chosen as normal. R coefficient can also be taken as 4. (if other conditions of the regulation are also suitable) c- If high ductility level curtains are used in such buildings, although such tiled systems are normal ductile, they can be selected as high ductility level or mixed according to alpha(s) value and R coefficient can be determined accordingly. . d-Floor floor and beamless slab systems without curtains are allowed only if the floor height after the basement, which is considered as rigid in the 3rd and 4th degree earthquake zones, is below 13 meters. (i.e. about 4 floors) Normal tiled frame systems without e-Curtains are permissible if the floor height is below 25 meters as normal ductile. (that is, approximately 8 floors or 9 floors if the gallery is floored) f-Frame systems without curtains with high ductility level (R=8) can be used in every earthquake zone. There is a regulation-based relationship between the gR coefficient and the ductility level. But these selected R coefficients represent the maximum values that can be selected. In other words, if we actually choose the system as ductile, evaluate all the conditions related to ductility and choose the R coefficient as 5, it would be stupid, but would the result be wrong? I just think that we would have made a more costly structure. Do you think it is true? h-1. Or, let's say that we solved the building as high ductile (R=7) by providing the necessary alpha(s) values by placing a sufficient number of high ductile shears in a building with a hollow floor in the 2nd degree earthquake zone. In such a solution, the frame system is normally ductile, whereas the system curtains are actually highly ductile. In this context, since the frame system is not highly ductile, is it necessary to check the column-beam junction area on it?

 

[teknikisler]

Let me add to what you said about hollow slabs, you said that hollow slabs are considered normal ductile and you said that they cannot be made as a frame without curtains. Also, at a point I don't understand, when we get R=7, do all the curtains we put in the system have high ductility level (even if R = 7 after B1 irregularity and alpha s controls)

Hollow slabs will be accepted as normal ductile, It is stated in the earthquake code. But if the design is made using high ductility level curtains and other alpha s requirements are fulfilled, the earthquake code says that the system can be accepted as high ductile and R=7. In my opinion, even though we have solved the system as high ductile, the frame system should still be normal ductile. In this case, too, the high ductility frame systems I think that there is no need to check the lon beam junction area.

 

[teknikisler]

1. In the investigation of the relative floor drift, if there is a heavy exterior wall in our structure, these calculations will show great differences. Is it possible for us to calculate this or to enter this exterior into the program? 2) It is generally preferable to prefer the mixed system. I know that it is suitable for high floors, do you think this is true, or what is the truth? Thank you.

1- If there is an exterior in the form of cladding or sheathing, I think that these loads can be loaded on the beams as wall loads. You can do the wall load analysis accordingly. I don't know if such a generalization exists.

 

[teknikisler]

Anyone want to have another opinion?

 

[sereze]

1-Semi-rigid gives more realistic results, especially in the full-rigid option in hollow slabs, the program transfers the entire load only in the direction of the hollow beam beams, whereas there is load transfer in the direction where the hollow slab is weak. 2- It was an elevator that we consulted with a mechanical engineer and made a column-beam-frame. 3-I think that the elevator machine room, that is, on the last floor, will transfer load to the floor in the engine room through the mechanism where the ropes are tied. If we go into detail, when it brakes, it gives load to the curtains through the rails. But you don't need to worry so much. 4-Look at the floor offsets, if there is a much lower displacement than the normal floors, they are rigid. 5-g- Correct, in the geometry of the building, on the ground, on the contractor, etc. We have the authority to stay on the safe side if something happens that you don't like in any way. The result will not be wrong, we will stay on the safe side, the cost will increase a little.