Project Design and Problems Encountered

M

Mirza

Member
Since there is a field in the forum that I believe is lacking, I felt the need to open this topic. A project made by one of us may not find validity in the place where another person works, even though it is done according to the same regulations!... One of us calls la and the other says 'Lâ'. , violations, etc., share here, examine in an interactive way, discuss and resolve any problems... We want to do this; Getting rid of rediscovering America... In this sense, I'm waiting for your participation... Let me ask the first question to begin with... Question: You are designing a building with closed overhangs, provided that the limits in the zoning regulations (such as the front garden exit limit is 1.50m), the console distance you can exit. Do we have any limitations in the regulations? (as far as I know there is none) Or does your municipality (or project review mechanism) limit you in this regard? You can't go this far as a console, is there an obligation (imposition) like "You can't run a console statically this distance", not from the architectural garden limit? A municipality has fixed this limit as 2.10 m. It says that you cannot exceed this value no matter what your cross-section design is ;) (I leave the comment to you) I would appreciate if you could share the situations you encountered in this or engineering issues as I mentioned... good work, respect...
 
Re: PROJECT DESIGN AND PROBLEMS ENCOUNTERED A restriction that can not exceed a certain length is against engineering science. There should be no limitations after making the calculation that can keep the system alive with the engineer's account and knowledge. I can pull back further than the pull distance and make a bigger console. (I mean, even though there is a 1.5m pulling distance, I can shoot 4m, if my heart desires and can solve it, I can make a 2.5m console.) At least that's what I know. If anyone says no, take a look at the Ankara bus station (AŞTİ) where we all fall, is the length of the reinforced concrete consoles on the embarkation platforms 5m, 7m or 8-10m? Also, I think it's a good topic. In engineering, design is more important than calculation. Especially after the new regulation, this has come to the fore. Design is now important, not static calculation. The account part has become more technological. Another issue is whether the municipalities request and follow the required amount of space as a result of the calculation regarding adjacent nizm structures? Has anyone encountered a problem with this? What do we do in practice of the impact effect we tested on paper? With love...
 
Re: PROJECT DESIGN AND PROBLEMS ENCOUNTERED Dear NYILMAZ; Thank you for your participation... Unfortunately, the municipality I am affiliated with does not have any restrictions or controls in adjoining structures. Even worse, when one of the two adjacent buildings needs to be demolished, there is no action taken. Let alone the control of the impact effect, in a building to be built adjacent, even the level differences between the floor levels of the existing building and the building to be built are not mentioned, even though this situation constitutes a violation of the order in terms of architecture. That is, there is a building with floor elevations of +4.00, +7.00 ..., while in the building next to it, the floor levels are +3,00, +6,00 .... The columns do not hold each other, the building beams cut the columns of the other structure.. As you know, in the earthquakes experienced, in adjacent structures, beams were cutting columns due to this contradiction, and these cuts were occurring because the distance between the two adjacent structures to oscillate was not maintained or because there were elevation differences between the structures. As a result, I can say that there is no control, unfortunately, we always follow behind at the point of taking a lesson. As for what to do, if we do not have any architectural constraints, it may be possible to design the columns in a way that the columns are back to back on the adjacent facade, leaving a dilatation joint above the maximum displacement amount of the structure. If, architecturally, the columns do not come back to back on the adjacent facades and there are elevation differences as I mentioned earlier, the facades can be joined by making closed protrusions after moving away from the adjacent facades and applying the columns (maintaining the minimum dilatation). Let me end by asking one more question;)... It is appropriate to increase the "live load 150kg/m2", which is foreseen by the regulations and our teachers, on floors that carry non-bearing (partition walls) walls. The problem I am facing now is; We have a floor, the columns are connected to each other, you have created very beautiful frames, but in the architectural plan, there is a 20-inch wall in the middle of the floor you have created. What the municipality said, there is a 20 wall here, so you have to throw beams ;) when a beam is thrown there, there will be a stud beam, the frame will not be formed, moreover, instead of throwing beams there, I increased the live load by 150 kg / m2, or I created a linear load where the load is on that floor( It is a futile effort to say ....etc instead of beams (wall load of 20). Because you cannot explain, it is such a strict memorization that it does not break... Does your municipality have any imposition on you, or how is the practice in various municipalities at this point? ... thanks for sharing ... good work, respect...
 
Re: PROJECT DESIGN AND PROBLEMS ENCOUNTERED Municipalities can be very strict on these issues at certain points, but we may encounter the same difficulties in the on-site applications, not in the project. First of all, no attention is paid to the column and elevation differences in adjacent structures, and you can even look at the side of the masonry building in an adjacent area, you can build a building, connect them, and give spacing. they are not checked. Apart from defining extra wall load, we solve this problem with thin beams on site. If the beam does not come, we put thin beams, but how healthy is it, what are the opinions of my colleagues on this issue. I would like to bite. In addition, since this approach is not subject to control, I do not know how many people apply it, but I pay attention to this situation.
 
Re: PROJECT DESIGN AND PROBLEMS ENCOUNTERED you mean thin beam in floors; elements with a certain width in slab thickness? If I understand correctly, I have seen what you said before, but it does not make any sense theoretically... in practice, you have an element with slab thickness (12~15cm), a larger size (fi12~14) reinforcement is placed than the slab reinforcement, but this is not the case. How long can the application be? we have to ask ourselves this... imagine if your wall load in the middle of the floor is 650~700kg/m, whether it's a linear load, it's as if we accept that this load is covered by that section (beam beam)... Of course, the beam application will be beneficial, I cannot say that it is a wrong application, but I can say that it is an incomplete application, in short, there is no healing solution... in fact, both our teachers and the regulation have found the most practical approach to this issue, in my opinion, they said to increase the live load by 150 kg/m2. In other words, spread the linear distributed load in your hand to the unit area... they said, do this spread in the live load, since this distributed area load will not be in that area all the time... you will appreciate that making this increase in fixed loads will not be economical, even more so, it will not be realistic... Despite all this, I can't understand the imposition of my friends who are still in the control mechanism... I wish all these neglects and impositions to be fixed... success in the studies... respect...
 
Re: PROJECT DESIGN and PROBLEMS ENCOUNTERED Friends, in the mentioned cases, increasing the live load generally does not make a serious contribution unless the flooring reinforcement and flooring thickness are changed. I tell you from my experience that in these cases, when no intervention is made, you may encounter serious cracks in the flooring. As you know, in the assembly of flooring equipment, the masters do not place the floor mats and stands in a very regular way. It should not be left to the skill of the masters. In this case, I increase the floor thickness (min. 20 cm) and place a hidden beam inside. For example, a 60×20 concealed beam both distributes the wall load and increases the floor rigidity. Zoning laws in adjacent buildings do not allow for such restrictions. In other words, he cannot say that the floor heights of the adjacent buildings will be the same, this is not possible on an inclined road anyway. Here, doing our calculations well and dilatation at least 2 times the maximum displacement is the best solution. Good work.
 
Re: PROJECT DESIGN AND PROBLEMS ENCOUNTERED Mr. suatyy, Do you apply the hidden beam application that you have done in practice, in the design of the project as well? Or what is the attitude of the municipality you are affiliated with in this regard? As I said before, I'm not saying that this practice is wrong, I'm just saying that it doesn't make any sense theoretically, that there is no definition of "hidden beam" in the literature... you mentioned that the amount of reinforcement does not change; When doing the slab analysis, if your slab calculation axes only calculate the cross-sectional effects on the line they pass through and equip accordingly, it is true that the amount of reinforcement will not change, but if you change the properties of your calculation axis and say "calculate the reinforcement for the distance where it is valid", you can clearly observe the change... I suggest you try this, open any project you have, define a linear load on any slab (assuming there is a wall) and make the necessary changes in the calculation axes of that slab (valid Calculate the reinforcement along the distance where it is (by activating the option) and perform slab analysis... you will see that the reinforcements are insufficient and changed... after making the necessary changes in the properties of your slab calculation axis, without defining the wall load (or without introducing a linear load) If you analyze, it will be seen that the reinforcements have changed... but n It is preferred to equip a normal slab (without walls) according to the cross-sectional effects of the calculation axes only on the line (usually at the middle distance in orthogonal slabs) as it is the most economical approach... the system is idealized and solved with an average approximation... is correct) otherwise, calculating the moment for each slab calculation line and having the reinforcement calculated accordingly will be both a difficult task and cause uneconomical results... There are definitely more than one solution for only wall-bearing slabs. I trust your approach and experience, of course, your approach is at the point of application. it's true, but my intention when I first opened this issue is not to test anyone's experience (which is not my place), on the contrary, the attitude of the project supervision mechanisms to the solutions brought... Maybe it will be again, but the question is, in short; On a floor with a 20' wall, is it compulsory to put a beam under that wall by your municipalities? Since I am in a mechanism that imposes this, my wish is to learn if there are such impositions in other places, and to act with a common mind by sharing the problems faced by a project developer. Thank you for your relevance and comments... success in your work... regards. ...
 
Re: PROJECT DESIGN AND PROBLEMS ENCOUNTERED Konya municipalities also demand the obligation of laying beams under 20-gauge walls... Hidden beam is not in compliance with the regulation. Because according to the regulation, the height of the beam should be three times the height of the floor... I usually throw beams at the minimum height (25/36)...
 
Re: PROJECT DESIGN and PROBLEMS ENCOUNTERED Hello; I have questions about Performance Analysis, I would be glad if you could help me... The project has a comprehensive knowledge level, the concrete strengths measured in a building are small and a performance analysis is required... The total height of the building is 24 m including the basement and the total height is 21m since the basement is rigid. is The design of this building was done in İde... Now the question is... 1. What should we do in order of priority while performing the performance analysis of this building... 2. Is it necessary to make "Analysis-Reinforced Concrete" according to the result of the concrete extracted with the core... If "Analysis-Reinforced Concrete" will not be done again according to the core result, how will we determine the concrete class in order to determine the performance... 4. After writing the concrete class and the value obtained as a result of the core, it is necessary to lock the reinforcements of the existing beams/columns and curtains and perform a performance analysis.. 5. Performing the analysis according to which parameter while performing the Performance Analysis gives better results (max displacement, a certain displacement of the building height, the number of plastic hinges...) I am waiting for the comments and opinions of friends who have worked on these issues before and have knowledge... Thank you for... I wish you success in your work...
 
Re: PROJECT DESIGN and PROBLEMS Hello; 1 a. First of all, you should define to use the existing concrete class determined at the end of the core tests. b. The existing (ie used in the application) reinforcement class should be defined to the column and beam elements by paying attention to their diameter, number and spacing, and you should "fix the reinforcement". c. If stirrup tightening is done in the application, check the option that stirrup tightening has been done from column and beam properties, if not, this option will not be ticked. D. After making the definitions above and creating the model completely, make Analysis+Concrete. to. Then do a Linear Performance Analysis. When making DPA (for your project), select the Mode Combination Method, Comprehensive Information level, the last two options are up to your preference, the necessary explanation is made in the What's This section. 2. Of course, you will do analysis+reinforced concrete according to the results of core and reinforcement screening test, if any. Errors and deficiencies that will arise as a result of this process are not taken into consideration as performance analysis will be performed. 3. ... 4. It is important that the DS is checked during analysis+reinforced concrete whether it is checked during performance analysis or not. 5. The parameters according to which performance analysis will be made are explained in chapter 7 of DBYBHY2007. I wish you good work.
 
Re: PROJECT DESIGN and PROBLEMS ENCOUNTERED thanks for your comments... good luck with your work...
 
Re: PROJECT DESIGN and PROBLEMS ENCOUNTERED Hello; I have a few questions for sharing information about a subject and its applications, which I have just encountered but I think there are experienced friends among us, and thanks in advance for your interest and help... As you know, the Building Inspection Law and the relevant regulation have been put into practice all over the country. A table with the name 'Static-Reinforced Concrete Project Review Sheet' was prepared in the regulation and 'Yes' or 'No' boxes were left against the phrases in the table... I have a few questions about the said ruler... Subject I'm waiting for your comments about... Is it a necessity or a recommendation to have all the boxes in the review sheet as 'Yes'? What is the binding of 'Yes' and 'No' there? Are there some items that are blocked now even though there are designs we have made so far? (If 'yes', what are their theoretical theories?) While the limitations mentioned in regulations such as DBYBHY, TS500 and TS498 are based on a theoretical/experimental infrastructure, some phrases written in this table seem as if they were written with the approach of 'It would be better this way'... I hope we can discuss with detailed concrete examples... good work, regards...
 
Re: PROJECT DESIGN and PROBLEMS ENCOUNTERED First of all, I would like to state that I am not a building inspector, so I agree with this subject because I am interested in this subject. We also discussed the subject you mentioned in my presentation in Amasya today. All of them must be yes on that form. This form is a form published by the Ministry of Public Works for building inspection companies to ensure that these issues are controlled and to set a standard for the control mechanism. Here are some issues that you see more than the minimums in TDY and TS 500. These are the improvements made to eliminate some of the problems seen in the application. For example, min 30 cm column width. The minimum TDY is 25, but the beam minimum is also 25. In this case, the beam reinforcements that sit on the column parallel to the column and the column reinforcements overlap and you cannot apply the rule that the column reinforcements wrap the beam reinforcements. Since we cannot make the beam of 20, making the column of 30 is the most practical method of this. There are also points that are understated or absolutely wrong in that form. A few examples; Construction periods are not asked, they should be asked. Moment diagram cannot be taken for a certain point in shear walls, but the total moment of the section can be taken, but shear diagram is more important for shear walls. This too should be asked. Incorrect suspension reinforcement on stud beams leads to inconvenient results. Instead, stirrup compression and body reinforcement should be placed and checked. and so on..... Suat
 
Re: PROJECT DESIGN AND PROBLEMS ENCOUNTERED Hello Mr. Suat; You said "all of them have to be yes on the form in question". For example: "There is a vertical load-bearing element extending across more than one floor in the building" is it okay to say "yes" to this statement? What does "no" mean? You are modeling a single storey building, can't you make the short side of the column 25? If we make the short side of the column 30 and throw a hollow beam on it (like 60/35), will the column wrap the beam? I think it is due to a situation related to TDY Article 3.4.3.1 (interlocking of beam reinforcements). because min. reinforcement diameter and min. The column size may have been increased because the item in question is not provided with the element dimensions, or as you said, it seems to have been prepared with the logic of how we can prevent this situation with the project, considering the problems in the application. I mean, with some materials, engineering and architectural design are restricted... * "Sudden changes in stiffness in vertical load-bearing elements (such as the transformation of the shear into columns on the upper floors from any floor) are avoided. (Even if the sections seem sufficient as a result of the calculations, da)"........yes, it's a good thing, it can be requested, recommended but not imposed... * "The ends of the columns are connected with continuous beams to form a frame in closed building overhangs. "..........it can be requested, recommended but cannot be imposed...(contained overhanging structures will still be designed architecturally and the solution will be found on hollow floor tiles, because no one wants a beam hanging from the middle of the room, hollow floors I don't need to say anything about it, you already know your problems...we are embracing the types of flooring that the authorities are shouting at and saying "avoid") Also, if we talk about this article, what would be the ruling of this article for a cork flooring? I tried to express it clearly, of course, simpler, simpler is safer, but I think we should not be afraid of different designs... Authorities, who do not impose any restrictions or supervision on the contractor, master, worker at the point of application, said to the designer, "Look, in practice, because of this They are doing this wrong, let's do this and that in projects to absorb their mistakes". The implementation is done according to the project that I know of, the project is not designed according to the application... if the implementer does not know, it would be more appropriate if the implementer did not know, to strengthen the control mechanism, even to apply some deterrent penalties, to issue a license... I would like to talk in more detail, I do not want to bore you too. . By the way, one last question; What would happen if there were "No" in the said project review chart? By the way, I would like you to know that I am not a building inspector, I am writing these as a designer... thanks for your patience and interest... good work, respect...
 
Re: PROJECT DESIGN AND PROBLEMS ENCOUNTERED Dear Mirza, I took your name as Mirza, if not, please warn me. I do not know your project experience and please do not take this on yourself. Regulations give minimums. They are not completely correct, so they are often revised due to the detected problems and the necessities of the day. Although the 25 cm column looked problem-free on the project, it was causing many problems in the field. The problem of wrapping the beam reinforcements I mentioned is just one of them. The hollow floor beam you gave an example cannot be considered ductile anyway. Cork flooring is also at normal ductility and is subject to different controls. Due to the ductile structure, we take the R coefficient as 8 and seriously reduce the earthquake force. However, the first condition of ductility is that the rigidity of the joints is not deteriorated. This error we're talking about breaks this combination. Many examples were seen in earthquakes with this type of dispersed combinations. Another problem is that the spacers are 4 cm in accordance with the fire regulations. This is also the case in Europe and America. Can you remove the 8 cm cover from 25 cm, what do we have left as a column? 17 cm. Do you think it is enough? I have never used 20-gauge columns since 1989, I have used body iron in every beam without exception, but the requirement for 25 cm columns came in the 1998 regulation. If the columnar structures built at this time of 20 cm have somehow passed the license period, they cannot obtain a license at the moment. There is no such problem when I do it. I've been using a 30 column for a long time, after seeing these problems, I'm sure after a while the column min. width will be 30 cm. Regulations shouldn't restrict engineering, you're right, it should be very simple. However, let's not forget that there is no specialization distinction in civil engineering in our country. An engineer who has worked on the highway for 30 years can come and do a static project the next day. Unfortunately, our engineers have endless authority regardless of any qualifications. Regulations seek to prevent such serious errors. It cannot be said that all of the engineers of the building inspection companies in the position of project control are experienced in these matters. These forms have been prepared to ensure project supervision with minimum errors and to bring a standard. All of the topics you have listed have been prepared in order to minimize the mistakes that are not written in the regulation or clearly written, but which are frequently made by novice engineers in the market, which will have serious consequences. If, as in Europe, it requires an experience of at least 5 years and an average of 10 years for an engineer to be authorized to sign, if the specialization mechanism works seriously and passes serious exams, believe me, neither these forms nor the regulation will be needed. "Sudden changes in stiffness in vertical load-bearing elements (like shear walls transforming into columns on upper floors) are avoided. (Although the sections seem sufficient as a result of calculations)"...... Look at the build-and-sell buildings, most of them are sitting on the floor. Consoles have serious cracks. It was written for this reason. You are right, it has been imposed because there are not enough experienced engineers, but I wish all our engineers would see this problem and impose it, if these problems did not exist. Hollow floor slab is extremely inconvenient in the 1st degree earthquake zone. However, in some areas, you may need to make toothed flooring to hide the beams (this is how I solve these problems), you do not need to fill the entire structure. You create the main axes with beams, you guarantee the ductility of the structure, then (the beam does not need to be in the middle, you can create the console area on the ceiling as a low floor). This type of structure does not perform as well as fully ductile, but it is the best of the worst. You should not be afraid of any building designed by a good engineer, but look around you, how many engineers can read the earthquake code to the end. In the meantime, in order to be able to read earthquake regulations, structural dynamics, finite elements, theory of elasticity, and earthquake dynamics etc., which are graduate courses. I want to remind you that you must have taken the classes.
 
Re: PROJECT DESIGN AND PROBLEMS ENCOUNTERED Hello Mr. Mirza, Mr. Suat. Actually, you are both right, but ts500, tdy2007, structure inspection app. regulation does not contain the same rules. Of course, there is the fire code. Regulations need to be updated urgently. Meanwhile, the building inspection regulation was prepared while it was being implemented in 19 pilot provinces, and there were 30 cm forcings for provinces with high earthquake risk. However, in small two-storey buildings in Karaman, I think this is not necessary.
 
Re: PROJECT DESIGN AND PROBLEMS ENCOUNTERED Dear Tvekkul, The issue here is not the number of floors. It is to accept a ductile behavior and reduce the earthquake load, and to make a non-ductile joint due to this type of connection errors. Even if it is a single storey, let's not make a mistake like this. There are many single-storey or two-storey buildings destroyed in the Erzincan and Düzce earthquakes. The problems and errors in the regulations do not end. The new one will also have a problem. As I mentioned before, regulations are written to minimize the risk of making vital mistakes. This is not the only point of conflict. Let me just give one more example, when calculating shear strength Vr, there is a coefficient Vc for the concrete admixture. For different values of this coefficient, see TDY in TS 500. You go to TDY, at the relevant point, he says, see TS 500 for different values of this coefficient. You come and go between the two regulations. What do you do in this situation? Wouldn't you take this coefficient just because it doesn't exist? Of course no. In this case, you get whichever coefficient leaves you on the safe side. One more example. You know, it is not possible to recover the shear safety of column-beam junctions without interfering with the architecture. Any beam that sits on the columns from the side and at the end of the column does not save this control. Is it because it really didn't save? No, the Regulation is a deficiency in the formula. Here, Ve is expected to be greater than Vr. For Ve, a shear capacity is calculated by taking the lower and upper reinforcements of the beam according to the earthquake direction. but for Vr, only the concrete cross-sectional area of the column that the beam pushes is taken. However, in order to prevent shear cracks to be controlled here, stirrups are also placed in the area of the columns corresponding to the beam, but these stirrups are not taken into account in the calculation of Vr. It is a formula prepared by staying on the very safe side. So, are we going to skip this check just because we know the deficiency in this formula? No, because the placement of beams in this area has not yet become a habit for all blacksmiths and we do not trust the control mechanism that much yet, so we do this again to stay on the safe side. In short, I think all these controls are necessary. Here, we must spend our energy to find solutions to such applications that cause errors in building behavior. A blacksmith who could not place the column stirrup we mentioned said to me, 'I cannot place this stirrup here, if you know, let's put it on the show'. At that moment, the man was right, asking for a solution at this point. I thought a lot and found a solution and had it done by the master. Greetings
 
Re: PROJECT DESIGN and PROBLEMS ENCOUNTERED Mr. Mr. Suat, your observations are correct and good. I resigned. As you stated, Erzincan and Düzce are cities within the active earthquake zone. However, I have mentioned the provinces with relatively less earthquake risk. For example, there is no previous devastating earthquake in the center of Konya and in many of its districts. While this is the case for many regions of Turkey, we all design and inspect earthquake resistant structures. For example, in Karaman, which is in the 5th earthquake zone, the projects are already being solved like the 4th earthquake zone, they should be solved. But 2-storey structures with high ductility level are not solved (not necessary). Therefore, there is no need to verify the shear safety of the column-beam junction that you have already mentioned. In addition, since the earthquake thrust on such structures is not very much, we see that even if we use a column size of 30 by 20 and take the R coefficient of 1, even if we solve the projects as zero ductile, we see that it saves the calculation. The important thing here is to carry the vertical loads safely and transfer the loads to the foundation safely. In addition, considering the earthquake lateral load effect, the length of the vertical carriers is more important than the width. The extension of the neutral axis increases the capacity. Therefore, using curtains in buildings is the most important measure to be taken against earthquake risk. The thickness of the curtains is limited to 20 cm. The floor space on the curtains is the same as on the columns. Likewise, beams are attached to these vertical carrier elements.
 
Re: PROJECT DESIGN AND PROBLEMS ENCOUNTERED Dear friends, Our friend Suat explained the event by giving a good example about our regulations. Now, after graduating from school and entering the market, friends with a computer, a package program and earthquake regulations say that I entered the project in the program, the program knows (checks) the regulations, it should give me the right solution, even I don't know regulations, I don't know static or reinforced concrete for me. They say to do the work. This will not happen, friends, after you create the project in your package program, I say that the ENGINEER should see that project, you cannot say with the master's head that the horizontal load will be less here. In our opinion, look at the UK, which is not in the earthquake zone, which regulations are below us, and it is not in the earthquake zone like us. Thank you all for your contributions.
 
Re: PROJECT DESIGN AND PROBLEMS ENCOUNTERED Dear Tvekkul, Please don't be offended by my words, I'm not saying this to offend you. I guess I'm older so take it as advice from you. First of all, do not rely too much on the earthquake map. Do not be so sure that after a few years new faults will not be activated and the map will not change. There have been examples before. As an engineer, you cannot design only for vertical loads just because we are in Karaman. There are some unchanging rules in the building, regardless of earthquake or region. The most important of these is the strong column rule. As a simple physics rule, we have been applying this rule since 1989, which our new graduate friends encountered with the 1998 regulation. However, due to our engineer friends who could not think of this physics rule, they entered this regulation. What is this rule? In a strain, the weak spot breaks. If you build a 20-gauge column just because we don't have an earthquake here, it saves calculations, look what a simple sitting under a column does to your structure. The fact that your earthquake load is light does not change the basic engineering rules. The fact that the curtains are given a minimum of 20 does not mean that you can put 25 on the head of this curtain. In this case, you can either make the curtain 30 cm or use a curtain head 30 cm wide. The width of the elements is important as well as the length. Because structures are 3D. It should be of sufficient strength for loads coming from both directions. Greetings
 
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