Yeah sorry about, i was quite confused when everyone thought it was nothing. The axial load alone pushes moment magnifiers too high. Otherwise it could work.
Ive gone and made a fool of my self 160MN (160000kN) is the actual load. Sorry guys I typed it wrong. No wonder noone was as worried about it as me.
I've assumed pin-pin for this column.
Hi DIK,
Its 20m high 100 MPA. Its a pretty scary colun to deign to be honest.
Hi Strook,
I say that because there is a point when the eccentricity you design for seems unrealistic. I ask this because for the case of this column 100mm eccentricity for a 20m column taking 1MN is a bit large...
Hi Strook,
This is actually a concrete column supporting a massive structure at the bottom levels. Its a 2m by 2m concrete column. It is a very slender column so moment magnification is is pretty big.
In my mind it makes sense to limit the minimum moment provisions after a certain size of...
Hi Guys,
I am currently designing a rather slender column with a very heavy load on it, Upwards of 1MN. I just wanted to ask people's opinion on designing this column for minimum moment.
Due to the size of the column the minimum moment eccentricity exceeds the allowable tolerances stipulated in...
Hi Gusmurr,
Below is an image to one of the nodes with a stepped face on the node strut interface.
here is a link to the actual document, the image above is from page 126 if you would like to see it.
https://ctr.utexas.edu/wp-content/uploads/pubs/5_5253_01_1.pdf
Below is an image of a node...
Hi All,
Does anyone know if some of the nodal geometries shown in the document 'strut and tie model design examples for bridges' complies with the Australian code. There are some geometries woth stepped nodal faces and nodal faces that are unstressed. To me this doesn't seem like an issue but I...
Rapt,
Yeah I emailed and asked and they also confirmed that the neutral axis is taken at the steel depth not the section depth.
Captain slow,
its just a test column. Don't know why I selected that to be honest.
Also the project has multiple column types with a range of concrete strengths...
Yes I didn't account for the steel area but that shouldn't result in the difference between the two calcs. The difference would be small compared to what is shown between RCC and the hand calcs.
So apparently RCC Inducta use a parabolic stress profile but take the point of zero strain at the tensile steel depth.
I have attached my hand calcs that shows results when the 0 strain is at the face of the concrete.
I have attached the RCC output for clarification.
Do you guys think that...
Hi Rapt,
Sorry when I said it assumes I meant to just state the the ratio depth to neutral axis is reported as 1.379 in RAPT when I did the analysis.
That still does not explain the different result that RCC is getting. It seems the extreme fibre where strain is equal to 0 is taken at the...
I've checked the load factors they are all the same. For a 1000x200 (5N16s top and bot) It seems the difference is coming from assumptions each program is making. RCC is assuming a Ku(dn/ds) = 1 while structural toolkit and rapt assume a Ku = 1.379 (dn/ds = 200/145). This is 35mm cover and N12...
Hi all,
Has anyone used INDUCTA RCC for column design recently (with the AS3600:2018 code incorporated)? I have currently run a few column designs using it and noticed that the decompression point calculation is wrong. Now I just want to confirm if it is actually wrong or if I am missing...
Hi all,
Regarding the new concrete structures code, can anyone guide me towards resources that can help me understand what is happening with the shear calculations. I know how to use them but I don't fully understand the mathematics behind them (for example what is the kv value exactly and...
