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If you really want to go in details, then see RISA explanation what it does in finding critical parameter; https://risa.com/risahelp/risafoundation/Content/Common_Design/Punching%20Shear%20-%20Design.htm Goto " Finding the Controlling Case (Interior, Edge or Corner) " section and see how many options are there to find punching perimeter; you can do this manually if the column is very critical.

The provision you are talking about is performed in other softwares like ADAPT, but I could not find such definition of edge/corner columns in ACI. Can you please share where it is written in ACI code? I dont think there is such provision in ACI. If you read ACI-318 2008 R11.11.1.2, it says "For edge columns at points where the slab cantilevers beyond the column, the critical perimeter will either be three-sided or four-sided." So draw punching perimeter around column and see if it lies inside the slab, then take it as interior column. (SAFE does this, if you keep the column location Auto). If any edge of punching perimeter lies outside the slab footprint, ignore that edge. In your case of example attached above, the column should be taken as interior column.

And before that, make sure the document is really from ACI? (I also dont know about this clause, so please let me know, I am learning from you). Because the document you are referring says "ADAPT Technical Notes", its does not look like official document of ACI. And remember ADAPT program is used for PT slabs. ( I mentioned this in post#14 as well). Also you still have the option to overwrite punching perimeter (as he said in post#7). Show me the edge column definition from some standard ACI paper or code in next post. (Not from the documents you have already mentioned). Thanks.

The document section I have quoted clearly says the clause you were mentioning is for prestressed sections. Now you have attached the summary that explains the intent of the document that the clauses in this document are written for the design of prestressed and non-prestressed concrete sections (same like ACI). Based on this you cannot say that all what is written inside is applicable to both. Each one of them is treated separately. The section I quoted above is for "Prestressed". Instead of putting links and reference to other items, why don't you show me directly where it is written in ACI the definition of edge column with distance less than d/2? So that we can talk directly on the specific point instead of loop referencing! I have not read the documents you attached the link for, in your last post. Please take a screenshot where it says specifically, and attach it here.

Salaam everyone! I wrote these scripts a few years back when i was working on my final year project. Definitely spent a lot of time & effort. I remember searching for any hints when i was about to embark on this project... This code may however be most useful for students & any pedagogic purposes while its application in real scenarios can't be denied either! My Project.zip

Moreover, SAFE methods are based on Amin Ghalis book for deflection and punching. You can read his book for insight. (Author of this technical article as well)

Have your really read the paper you are mentioning? This paper talking about distance < 4d is only applicable to "Prestressed slabs".

W.s So the SME says that if there is only compression, the cold joint shouldn't be an issue. But if there is moment in the foundation at cold joint location then reduced stiffness properties shall be considered. I don't know what the foundation framing is? Can you share that- probably a line diagram? Thanks.

Ws. I can see the concern of the Lender's Engineer. For a turbine foundation, with an unintentional cold joint, he may be worried about vibrations and subsequent crack propagation. Well the irony is that you can't really have machine foundation poured in a single unit (unless its a simple small square pad). It has to has construction joints or sometimes unwanted cold joints. Given the nature of problem, a super-imposed beam would not add any value to given problem. This approach shall make sense if you only think inside static design bubble. However, considering the limit states for turbine foundations, the addition of beam may not help. Here are two solutions: 1) Static Design: Your engineers should demonstrate that enough reinforcement is present and crack control is not a problem. I have done huge compressor foundations and have allowed construction joints where required. Joints are inevitable and shouldn't be any problem. The impact of a cold joint on machine foundation is somewhat hard to assess as there are so many factors involved-quality of joint, location of joint, support framing . The above stated solution is an acceptable one if the dynamic loads being produced by turbine are very small- dynamics analysis wouldn't be of any significance. 2) For significant dynamic loads: This solution is applicable if your turbine dynamic loads are significant enough to affect foundation response. Talk to your engineers to see what limit states governed foundation design. If your foundation is table top, re-check the foundation using reduced section properties(since concrete is cracked). Normally, machine foundation design(other than table tops) is based on the assumption of rigid block and no one would consider reduced properties when checking response of foundation against dynamic loads. If your engineer re-checks the foundation based on reduced section properties(If foundation is table top) and amplitudes are still below the maximum limit, and there are no resonance issues, you shouldn't require any modification at all. However, You still need to add the crack control check to ensure that enough rebar has been provided and cracks won't propagate. Don't float this idea to the Client unless someone who designed the foundation has actually done the check. Unless the foundation is excessively over-designed, this condition shall be very hard to meet. I will also discuss this with dynamic analysis subject matter expert and update you on what he thinks. #2 is a conservative way and is just one of many approaches out there. So, adding a beam would do nothing to your wind turbine foundation. If the beam being added is a huge beam, it would add some/ little mass and damping to system but the response of the beam is not related to what your question is about. The question is also about what kind of dynamic loads are present. I have never seen any vendor data of wind turbines and can't say about kind of dynamic loads produced by them. If your dynamic loads are significant and foundation type is table top, see point 2 else point 1. I hope this helps. Keep the updates coming. Thanks. Update: Regarding Point #2, for table top machines, reduced Section properties should be used. For rigid blocks, cold joint will not have any significant affect as foundation will be most likely in compression.