Splitting ribs exceeding 4 meters

M

muhsin34

New Member
I wonder how it would be if idecad automatically divides the ribs that exceed 4 meters and throws a rib in between, even though we do not look at which flooring exceeds 4 meters one by one.
 
I recommend that you check how the slab transmits the load when you make a cassette. Otherwise, your solution is not correct. I recommend you to divide the slab with your hand. You can also get information from the authorities.
 
actually, when we make cassettes, we make a healthier and more realistic solution... we distribute the load to the beams in both directions by the amount of ribs... but if you add a beam on the output, you do not define the load of the beam on the beam on which the beam is mounted.
 
If you define it as a tape and look at how it transmits the load, you will see that there is no load transmission as you mentioned. We thought that there was a load transmission as you described, but it is not, we have forwarded it to the authorized persons and they stated that they will try to fix this problem in the next update. My advice to you is to draw it yourself as a hatil, otherwise you will have made a whole mistake.
 
This issue will be clarified in the new earthquake regulation. It is likely that the regulation will require the inspection of rib and cassette systems with a semi-rigid diaphragm. After the regulation is issued, this situation will be handled together with other issues introduced or changed by the regulation. We are waiting for the new earthquake regulation to be published. When using cassette in ideCAD, there is no problem with load transmission between backhaul. Due to the nature of this System, it results in this way. Rib and cassette systems behave differently from conventional beam-column systems. If you want the system you mentioned to transfer the load to the perimeter beams in the most accurate way, you should not include the system in the model with flooring beams and cassette beams. For ribbed systems to work as you expect, the ribs must be in the short span direction and the upholstery must have an aspect ratio of around 2. If you throw the ribs in the long direction and expect that the long main beams will not be loaded, the system will not work the way you want. The ribs, which do not require transverse teeth as per the regulation and whose system is selected in the long direction, should also be resolved by including the flooring in the program. In the attached images, the ribs are thrown in the short direction in the system on the left, and they are placed in the long direction in the system on the right. When the results are examined, whether the rigid diaphragm or semi-rigid diaphragm is dissolved in the systems placed in the short direction, moments in the direction you expect have occurred. However, when we include the floors in the system where the ribs are placed in the long direction, the long beams become a serious load and a span of 4.138 tm is formed. Especially the solution of rib systems, where you place the ribs in the long direction and the flooring aspect ratio is not close to two, gives very wrong and wrong results in the solution with the rigid diaphragm method. The analysis made with the rigid diaphragm method, however, gives results close to the real solution in systems where the ribs are placed in the short direction. When solving with ideCAD, especially in rib and cassette systems, solve with the analysis option "semi-rigid diaphragm" that also includes floors. In the image below, the solution is made using the rigid diaphragm method. In the image below, the system floors, ribs and beam columns are modeled and solved as a whole, that is, a semi-rigid diaphragm solution is used.
 
"muhsin34":2vgxls4n" said:
I recommend you to check how the slab transmits the load when you make a cassette. If you define it as a tape and look at how it transmits the load, you will see that there is no load transmission as you mentioned. We thought that there was a load transmission as you described, but it is not, we have forwarded it to the authorized persons and they stated that they will try to fix this problem in the next update. My advice to you is to draw it yourself as hatil, otherwise you will make a whole mistake.
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It is very normal that the results come out like this when you make a cassette tape. And loads are transmitted correctly. When this beam is entered into the system, the result is like this. If you wish, this transverse female will not be inserted into the system and you can add it to the drawing later. However, no one can guarantee you that what you are doing is correct in every system. No one can guarantee you that long beams will not be loaded, even if no transverse teeth are added.
 
When I defined it as a cassette and checked the load transmission, I saw that the cassette beam I defined after 4 meters transferred half of the floor load to the other beam. Now, if this were literally a cassette, that is, if it worked in two directions, the result would be correct for this slab, but it is not correct for a single tooth to transfer half of the load of the slab to the other beam. When I checked in the semi-rigid solution, the same load transfer is wrong. When I wanted to explain, I couldn't understand exactly what you said
 
"muhsin34":1ihln6zr" said:
when I defined it as cassette and checked the load transmission, I saw that the cassette beam I defined after 4 meters transferred half of the floor load to the other beam. It is not correct that the tooth transfers half of the load of the floor to the other beam. When I checked in the semi-rigid solution, the same load transfer is wrong. Write that the load is being falsified. However, please use a simple ide file with 4 columns. click it.
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There cannot be a natural and normal situation as the moment increase due to the transverse tooth. The transverse thread increases the opening moment of the beam into which it is inserted. You think that there will be no moment increase due to the transverse thread, you just show this thread in the drawing. But what you are doing is not correct. Information of the modeled system: Columns 40x40 Beams 25x60 No Duavr load 4 x 6 meters floor height 3 m ribs 10x35 rib spacing 40 cm floor height 7 cm Coating 0.15 t/m2 Q 0.2 t/m2 Combination where torque values are given 1.4G + 1.6Q [b ]Full Rigid Diaphragm No transverse threads[/b] Full Rigid Diaphragm Transverse threads Semi-Rigid Diaphragm No transverse threads Semi-Rigid Diaphragm ( elastic diaphragm ) Transverse threads Analyze your ribbed systems with a semi-rigid (elastic diaphragm) analysis option by including slab finite elements, whether they are transverse teeth or not.
 
Hello friends, when we solve the ribbed floor as a semi-rigid diaphragm, the reinforcement in the rib beams always gives as 4Q10, if the floor is 5m or 9m, it still gives 4Q10, but in full rigid diaphragm, extra reinforcement is thrown in the form of pillars or as additional support reinforcement, I wonder what is the reason for this?
 
Hello, in one the slab is fully rigid, the rib cassette system does not displace together with the beams, the other is semi-rigid, the slab shows elastic behavior, the plate between the ribs, the ribs and the beam system dissolve and displace together. Accordingly, it is normal for the rib opening moment to be less in the semi-rigid diaphragm solution, which affects the rib reinforcements. The question you asked was explained in detail in the messages under this topic. Also what is a semi-rigid diagram, the information given in the following link will help you:
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"manzoor":1zm3poh1" said:
Hi guys, when we solve the ribbed floor as a semi-rigid diaphragm, the reinforcement in the rib beams always gives as 4Q10. If the floor is 5m or 9m, it still gives 4Q10, but in full rigid diaphragm, extra reinforcement is thrown in the form of pillars or additional I wonder what is the reason for this as a support reinforcement?
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When the span changes, either the full rigid solution or the semi-rigid section effects change. However, the more accurate result is semi-rigid solution. When the span changes, the result does not change. Add the project that you say always gives 4 fi 10.
 
"manzoor":exscci2a" said:
Hi friends, when we solve the ribbed floor as a semi-rigid diaphragm, the reinforcement in the rib beams always gives as 4Q10, whether the floor is 5m or 9m, it still gives 4Q10, ?
Click to expand...
This is not the case. You can see that the moment changes at different openings in a semi-rigid diaphragm. The reinforcement is the reinforcement that meets that moment. If we examine the attached sample projects. Aperture moments for the example without transverse teeth (rib example.ide85): D1 = 0.538 tfm 4m Span D2= 1.109 tfm 6m Span D3= 2.65 tfm 10m Aperture Moments Also in semi-rigid diaphragm solution, it varies according to the opening.For the example made by defining the transverse tooth, the opening moments (rib example_eninedişli.ide85): D1 = 0.475 tfm D2= 1.01 tfm D3= 2.386 tfm changes according to the aperture.
 
"manzoor":3ls78g61" said:
Hi guys, when we solve the ribbed slab as a semi-rigid diaphragm, the reinforcement in the rib beams is always 4Q10. I wonder what is the reason for this as support reinforcement?
Click to expand...
In the rib systems entered in the long span direction, the solutions obtained with the classical old drawing methods give far results. The new earthquake regulation to be released already clarifies this issue. I recommend you systems containing ribs and tapes, Solve it with semi-rigid diaphragm method.In this example, in the old approximate classical method, the main carrier beams in the long direction (K02 and K04) work almost without taking any load off the floor.But when the floors are involved with finite elements and calculations are made with ribs and main beams, this beams ( K02 and K04 ) contribute significantly to the system, so this example The semi-rigid diaphragm solution for k gives much more accurate, precise, realistic and economical results.
 
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