Raft Basic Reinforcement Amount Prediction !

M

mehmet sesigüzel

New Member
hello; I need the help of my experienced brothers as it is my first months in project design and using idecad. In the attached project, the basic reinforcement ratio seems a little too high to me. After all, the more we can apply the 3E rule in engineering, the more authority you have. If we list what I want to ask as follows; 1-) Although the Zem and Ks numbers were entered completely randomly, I tried to design a raft foundation by estimating that it would be between Zem=20-30 t/m2 and Ko=3000-10000, but how can we minimize the amount of reinforcement. by editing etc. ) 2-) How can we define the calculation axes that I have basically defined in a way that will make an optimum analysis. 3-) When we solve this structure in a semi-rigid diaphragm, the shear safety problem of the column-beam junction does not occur, but when we solve it in a fully rigid diaphragm, there are 2-3 columns that fall into the scope of this problem along the vertical. What is the reason of this ? 4-) I would like to thank my colleagues who will advise and help me as a carrier system or for my mistakes that I did not realize. I wish everyone a good work...
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1) In order to reduce the longitudinal reinforcements on the raft foundation, you can look at the ground tension control in the 3D frame, select the regions where the stress is low, and pass the reinforcement axles there. It will be beneficial not to pass the axles through that region in your project, where the stresses are formed in the regions where the columns and curtains are high. However, there will be additions in that region. 3) In fully rigid analysis, we think that slabs can transfer their loads to beams and columns without bending and twisting. Therefore, loads are directly transferred in fully rigid analysis. However, in semi-rigid analysis, horizontal loads will be transmitted less than they are, since slabs transfer by bending and twisting. The horizontal load transferred is equal (according to the slab). However, in semi-rigid analysis, distribution is completely made according to the rigidity of the slab. Therefore, it is normal for the situations you mentioned to occur. But I believe that full rigid analysis will give safer results in slab slabs. 4)* Connect the S17 and S19 columns completely, I think it is not appropriate. Also, it would be beneficial for the system to connect a column in at least 3 directions. Best regards.
 
"cakilomer":3oehvv58" said:
1)In order to reduce the longitudinal reinforcements in the raft foundation, you can look at the ground tension control in the 3d frame, select the regions where the stress is low, and pass the reinforcement axles there. .However, there will be additions in that region. 3) We think that slabs can transfer their loads to beams and columns without bending and twisting in fully rigid analysis. Therefore, loads are directly transferred in fully rigid analysis. In other words, the horizontal load transferred to the columns and beams in rigid diaphragms is equal (according to the slab). However, in semi-rigid analysis, the distribution is completely according to the stiffness of the slab. Therefore, the situations you mentioned are normal. But I believe that full rigid analysis will give safer results in slab slabs. 4)* Connect the S17 and S19 columns exactly, I think it is not appropriate. Also, connecting a column in at least 3 directions will be beneficial for the system. Best regards.
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First of all, I would like to thank you, Mr. Ömer, for your interest; Thank you, as you said, I adjusted the account axles. This arrangement reduced the amount of reinforcement, even if it was a little bit. As for the columns, you warned that you should connect the S17 and S19 columns completely, referring to the number of beams to which they are connected, I couldn't understand it. Could you please explain it to you again? (Due to architectural restrictions, I could only place it that way. I didn't like it actually, but it had to be like that ) I have one more question for you; *While creating a raft foundation, depending on the type of ground and the height of the building, the depth of the foundation and the ampatment projection can generally be increased by how much per floor. Now, I spend a lot of time using trial and error method to minimize it because I don't have experience. Could you please share your experiences with me... Best regards, I wish you a good work...
 
When calculating the front dimension height of the raft foundation, consider: Put it as the sum of the concrete thickness of the Deck on the foundation. If it is hollow floor slabs, calculate the concrete thickness of the slabs on the hollow block, this gives you a preliminary dimension, you look after the calculations and act accordingly.
 
Estağfurullah We have no experience, we just pass on what we know. * You can bring S17 and S19 columns to the same axis and connect them with beams. So if you need to make an L-shaped beam, make a Polygon column there. * In addition to our brother Sarıdurmus, if the raft foundation depth is generally 5, if the building floor number is 5, for example, 50 cm and 6, 60 cm, this is a very general approach, but it may vary depending on the situation. Best regards
 
yes, my gravelömer friend has touched the place where I did not write on the record floor. If you say the logic of the slab thickness (concrete) = the thickness of the foundation, you will approach it proportionally.
 
Thank you both for your help; If I think proportionally to the thickness of the deck, I need to build a very thick foundation. I was approaching with the logic of 8 cm thickness per floor, 10 cm ampatmany, and I have already concluded that this approach is reliable with the help of you. Thank you again, thank you..
"cakilomer":2wucs39b" said:
Estağfurullah We don't have experience, we're just sharing what we know. *You can bring S17 and S19 columns to the same axle and connect them with beams. In addition to our brother Sarıdurmus, if the raft foundation depth is 5, for example 50 cm and 6, 60 cm, this is a very general approach, but it may vary depending on the situation. You can go up to the minimum depth in Ampatman. But it will be more beneficial to go to the side where the stresses are. Regards[ /quote] I just can't help but ask you these problems, cakilömer: *I haven't tried the S17 and S19 columns because of the architecture, because of the architecture, that part will be a balcony, I even solved the hollow block without putting the S21 column at first. I didn't like it because it was too open, then I applied S21 I put it towards the end of the balcony, anyway, when I make S17 a polygon column, it does not provide column-beam cutting safety (torsion) on I didn't do this for flour, if the design can be done in a way that does not cause torsion problems, if you help that part in the form of a polygon column, it will be a treat :) *curtains that do not provide the ratio of 1/7 are always in our projects, I am asking based on your experience,'' This panel in the municipality is 1/7 Will I encounter obstacles such as not providing the rate?'' Best Regards, Take it easy ...
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*I can't say anything without seeing the architecture of the S17 and S19 column, but if the wall is making teeth, it doesn't have to pass under the beam, it can step on the floor, I think. *If the ratio of 1/7 is exactly at the border, for example, you can define the header area such as 25/170 and transfer it in the drawing in that way. Best regards
 
I took a look at your project. If you want tangible criticism on such a serious project, it is useful to put an architectural plan. In this way, no one wastes time in vain and makes a more accurate assessment. I would like to say 1-2 sentences in addition to what İbrahim Bey and my brother Ömer said. Although you are in the 3rd degree earthquake zone, your use of curtains in such a high-rise building (15 floors) should be curtains that contribute to the system as I always emphasize. You have no pitch in the X direction. PAN4 PAN6 curtains in the Y direction do not contribute to the system. We see that PAN3 and PAN7 are interrupted in continuity. Curtains are placed only on the points related to the elevator, arising from the architecture. There is no static curtain design in terms of improving the carrier system. I think you know what band beams mean: Constructive beams whose reinforcements are determined by the user, without any contribution to the calculation. Excuse my expression; beams we deceive ourselves. That's why I don't want or recommend you to apply. I wish you could have used beams that run through those corridors instead. If our architect brother (or our brother, sister, whoever) did not give you this concern. If a suspended ceiling on the floor of that apartment building turned the negative beams (?!) into positive with a play of light. There is nothing to be said for the S17 and S19. Because they said what they had to say. When they looked at the plan, they said "we don't fit here". As my brother Omar said, DO NOT build an interior console (called L) inside the building. It is difficult for us to make suggestions without architecture. But it was not what it seemed. No need for a book. Think of it just like architecture: Just as you don't like something that scratches your eyes in architecture, there is a problem in moving something that scratches your eyes in statics. Let me also write something that bothers me. It was a bit strange that in a 15-storey building there were 25/45 columns on one side and 40/115 or 120/30 columns on the other. Of course, there is a reason why there is no column at the intersection of K27-28 and K44 beams (I-11 axis). Stabbing another beam of 5.75 in a beam with a net span of 7.10? I think it must be unbearable lightness of working in the 3rd degree earthquake zone. Maybe what I wrote was like a repetition, but I wanted to make some highlights. Hopefully it benefits your business.
 
Hello my brothers cakilomer and NYILMAZ; First of all, I would like to thank you for taking the time to review and give advice.
"NYILMAZ":2n7o9qbq" said:
Let me write something that is strange to me. It was a bit strange that a 15-storey building had 25/45 columns on one side and 40/115 or 120/30 columns on the other side. K27-28 and K44 beams Of course, there is a reason why there is no column at the intersection (I-11 axis). I hope it will be of use to you.
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*The difference in my column dimensions, especially my 25/45 columns, as it can be seen from the architectural plan, I decided to put a small column there because the balcony is large. If you have any other suggestions, I would be glad if you could help. [quote ="NYILMAZ":2n7o9qbq"]Even though you are in the 3rd degree earthquake zone, your use of curtains in such a high-rise building (15 floors) is more, and as I always emphasize, it is a product that contributes to the system. should be leaders. You have no curtains in the X direction. PAN4 PAN6 curtains in the Y direction do not contribute to the system. We see that PAN3 and PAN7 are interrupted in continuity. Curtains are placed only on the points related to the elevator, arising from the architecture. There is no static curtain design in terms of improving the carrier system. [/quote] *When we look at the plan, how can we make the most appropriate curtain placement? I couldn't place curtains especially in X direction, since I couldn't place curtains in X direction in a balanced way, I didn't put any curtains. I would be very happy if you could help me... *Especially because there is no curtain in the front of the building, the front part is more deformed than the rear part, it is obvious that I need your advice to make a balanced curtain placement as you said, brother NYILMAZ... *In Bodrum K6-[b ]K7-K8-K9-K10[/b]-K11 Is the cause of the axial load excess in the beams due to the shear walls or is it due to a design error? In general, the project used 25/60 beams. *In general terms, I would like to thank all my colleagues who will tell me about my shortcomings in my project and give advice... ATTACHMENTS:
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"cakilomer":2oshmh7f" said:
Mehmet, I couldn't see the architecture, it says the file could not be found. Regards
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Omer, I refreshed the page, now I reloaded it, I think the file is not visible due to a technical problem... Regards
 
Our experienced brothers can predict a more detailed system. It is necessary to place the curtains in such a way that there is no rotational effect when placing them. In other words, we want them to match the stiffness with km as much as possible and to meet the earthquake shears in a ductile way, like a set on the outside. * Apart from that, if you are going to make a fully rigid solution, you should transfer the stair loads to the building elements. Best regards
 
Mr. Omer; First of all, thank you for your time and effort. As far as I can see the curtain layout from the plan, I need to arrange such a regular layout for such structures. But I can't help but ask this, I have been working for 2-3 months (But I still don't have a project I gave to the municipality). Now, as can be seen in the render, I couldn't use curtains in order not to lose the symmetry of the building facade and the window places. Now, when I cover most of the facade with curtains in 1-2 rooms of the apartments as you suggested, the architects will not like this situation, it is a fact. The fact of the matter is that I'm a recent graduate, the fact of the matter, and because my feet still don't touch the ground like an engineer, if there were another engineer tomorrow or the next day, "-he would do as we wanted, as this engineer was doing it,- no, we don't want beams here, we don't want columns here, etc", both from being crushed. I'm afraid how much I can listen to their wishes and compromise what we know. You know these things because you are more experienced than me. If an experienced engineer other than me was working, he would have given the necessary answer like a competent authority, but no matter how much I know, in their eyes, I am a new graduate. How can I break this image in the fastest way, how can I make it clear to them that these things will not work with architecture and aesthetics, with the spirit of an engineer who puts his strong feet on the ground... Best regards.
 
First of all, Mr. Mehmet, I put curtains without taking into account the window spaces in the plans you sent, because there was no window information if I remember correctly. You need to put the curtains in accordance with the architecture, this should not spoil the suitability of the purpose of use of this building. What the architects want is true without exaggeration. You can place curtains according to the plan. I tried to get information about curtains in many seminars. Curtains are elements that take shear force. It is important whether it receives shear forces in an earthquake when defining curtains. Therefore, in my opinion, curtains should be defined in high-rise buildings as an L-shaped corner or by forming a large core area. Also, the most important element that should not be overlooked in curtains You can define your curtains in a way that does not cause rotation. You can define your curtains in accordance with the architecture and examine them by looking at the shearing forces and rotational effect they receive. (My limited information is about curtains) The discourses you say about engineering can happen to all of us. I think the important thing is to be comfortable in conscience. Of course, knowledge is required in this. It is acquired over time when faced with different events. I am not in a position to give you advice, but I do this by myself, reading and researching all the time adds a lot to the person, but in some things it is based on experience. Best regards
 
Sorry I didn't have time to reply. More precisely, I did not have time to edit and try and write. You asked for an alternative to curtains. I'm adding them. (Analysis done. Problem does not appear). The zip file contains the architectural pictures you shared and the curtain options on it. If we design the living room and the hallway as a single floor, why don't we make the balcony and the kitchen. Provided that the loads are entered carefully, a whole flooring can be made to eliminate the problems that will occur in the architecture. I apologize for being late in replying. Maybe you have made the solution and have already gained some distance, but I wrote it because I wanted to share a different view for those who follow the forum. Good luck with. Good work.
 
Hello my brothers NYILMAZ and CAKILOMER; Thank you very much for your interest and helpful attitude you have shown. The alternatives and suggestions both of you gave opened my horizons a little more. I wish you a healthy and profitable working life. Stay safe, best regards... :)
 
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