Hello CEE, Thank you for this video, it has helped me a lot to kickstart a deeper dive into this subject especially with regards to defining custom cold formed sections (for roof purlins) with the goal to use these sections in the steel design module. This is what I have found so far: 1. It seems that the design code that is currently implemented in Robot for the verification and design of THIN-WALLED cold formed sections is EN 1993-1-3 2. In the case where one intends to use their defined cold formed custom sections for design and verification in accordance with the code in #1 above; It is important to identify that custom section as a “THIN WALLED section”, this identification can be done during section definition or by “manually editing” the section database where the custom section was saved to. [see reference below] Without the above explicit identification, Robot defaults to identify the sections created as ”SOLID SECTION”. Robot verifies and designs these “solid sections” in accordance to “normal steel design codes” such as the EN 1993-1-1 rather than with the cold formed sections design code in 1 above. 3. It is also possible to “copy, and then rename, and then edit as may be required” an existing section database that already contain cold formed sections on it. I prefer this method as it allows for a number of sections (with varying width, thicknesses, and heights, etc) to be available for the cold formed steel design module to select the more suitable section from during the design iterations. [see reference below] I was able to do both (I created my own custom “thin-walled” cold formed sections and I copied and modified existing cold formed sections databases). I have also successful-ish ran the cold-formed sections verifications and designs according to EN 1993-1-3. However, I have hit the following snags that I am wondering if the CEE may be able to assist with: 4. No matter how I had defined a cold-formed section; when I run the “member verification” or “the code group design” I always get a message (more like a waring message) which says that: “… the members are made from sections for which the EC3 code does not provide the formulas for calculating the critical moment. Mcr for these sections was calculated as for bisymmetric elements……” This is driving me nuts because I can’t understand why EC3 for example would not have formulas for typical sections such as Z and C purlins [these are the sections that I am getting the warning message with]. Am I alone in this? what am I missing that is causing this message? 5. The “member verification” or “the code group design” is ONLY using the bending moment that is applied to the member to verify or to design the member, the shear force is NOT being brought in or imported to the member design calculations. I looked through the "configuration" settings on the design calculation dialog box but I could not find where to “tell robot” to design for both bending and shear. Granted that it is possible to “manually” input the moment, shear, and even the axial force on the design results window although one would have to know the governing design cases for these pains ^_^ first in order to do this manual thing. I can’t understand why robot seem to be excluding the shear force in the purlin design? How can I ensure that both shear and moment (at the very least) are automatically imported from analysis to be used in the design module and calculations? 6. I have also noticed that the section “axes coordinate system for the section properties” that are being used with most [not with all, see reference] “thin-walled sections” databases seems to be the ones that assumes the sections’ horizontal and vertical axes co-ordinates system; the inclined principal axes coordinate system especially for the Z-section that was also mentioned by the CEE at 09:20 seem to be “ignored” by other databases … Given the analysis implications shown already by the CEE at 09:20 above, how significant is the omission from the design point of view of these Z-sections purlins in the case where the principal axes coordinate system is not taken as inclined? References: _www.autodesk.com/support/technical/article/caas/sfdcarticles/sfdcarticles/Robot-Steel-Design-How-to-code-check-a-member-of-Z-or-Sigma-shaped-thin-wall-section-according-part-3-of-code-NF-EN-1993-1.html _www.autodesk.com/support/technical/article/caas/sfdcarticles/sfdcarticles/ROBOT-STEEL-DESIGN-how-design-user-defined-thin-walled-section.html _www.autodesk.com/support/technical/article/caas/sfdcarticles/sfdcarticles/ROBOT-What-are-the-thin-wall-sections-catalogs-available-in-Autodesk-Robot-Structural-Analysis-Professional.html I have enjoyed this video, it has sent me looking (the CEE way ^_^) I like what I have found, and I am looking forward to the next videos. Keep well and kind regards, DK
Hi there Engr. DK, just for your information, you just helped me out MASSIVELY! I was doing some preliminary test on RSAP, and I missed this option! thanks a lot!!! you are the best and saved me some time in research
@@CivilEngineeringEssentials Hello CEE, Thank you for the feedback and for sharing your experiences. It really makes me very happy to know that you have found this comment to be helpful. It is such an honor for me to be of assistance to you. Your approach encourages me to “ask questions freely”, I enjoy our discussions and I find them to be very helpful and informative on many levels for me. Kind regards, DK
For anyone who might come accross the problem I had: When saving the section to the User database 7:14 I had no database to select. Fix: In RSA, go to Tools > Section Database: Create a new database "User" (in this case) Then, in Job Preferences, under Databases > Steel and Timber sections, you add a new database and browse to the newly created previously ("User") After that, the new database shows in the list 7:14 when adding new sections I would like to take the oportunity to applaud the extra info from eng. Donald Khanye to an already informative video from CEE 👏 Great video, great series (Industrial Warehouses) and great channel!
You are right. I even stated all possible problems in the RSA cold formed steel design during my warehouse series. Unfortunately, Robot suffers in terms of designing cold formed sections. Here is the video for your reference: ua-cam.com/video/kuwfiS6o0Bo/v-deo.html&ab_channel=CivilEngineeringEssentials Thnx a lot for your comment, it helps a lot. Regards, CEE
I have three issue regarding these user defined sections: -software doesn't do deflection check -sometimes the section become rotated after insertion and the dimension doesn't match the one used in the AutoCAD -Section is not seen in the database in the program data. What could be the reason. Kindly assist
If you are doing custom sections, you lose a lot of RSA's abilities. it is pretty unpredictable. For the section not seen in the database, please make sure you select the "user specified"database, not a standard database such as AISC> Regards, CEE
Hello, I want to express my gratitude for the fantastic learning content you provide on UA-cam. It has been incredibly helpful and enjoyable for me. I make it a point to watch one or two videos every day. 🙂 I primarily work with steel structures, such as purlins and corrugated steel sheets (Deck) without concrete and sandwich panels. I have a couple of questions: Can I define my section as a shell instead of beams in the modeling software (presumably referring to the software "Robot")? How do I define the overlapping of the plates (corrugated steel sheets) in Robot? Additionally, how can I calculate the stiffness of all plates together with stiffeners to account for wind loads? Normally, I conduct all my designs in Advance Steel or Revit. However, the last time I attempted to transfer my model into Robot, it only recognized the main structure and not my Z purlins and corrugated steel sheets. I would greatly appreciate your guidance on these matters. Thank you once again for your valuable content.
Hi there and thnx a lot for your comment. I am happy those vids help. Sorry for the long response in advance, I try to elaborate as much as I can to help you and your fellow audience. Ok, so first, defining the section of a beam as a shell: Short answer: yes you can, but you lose RSA's abilities to design those section. Long answer: yes you can, and each individual "plate" in your section becomes its own shell element. This is however, waaaay to much calculation effort, as you need to discretize your beam into tiny little pieces that would sky-rocket the calculation effort. So, although it is a theoretical "yes", I do not recommend it. As a secondary problem, you will lose any ability for robot to design that section for you. You are dealing with corrugated sheets only as your decks. So no concrete nor sandwich. I want to re-iterate your question just to make sure I got this right: So you are using corrugated sheets, which means that there is an overlap between two adjacent corrugated sheets, which happens usually on a beam/purlin element. Your corrugated sheets are overlapping because you want to "nail them" to the beam/purlin element. So, you are asking about how to model this deck. Please note that: you could simplify and just use the "single corrugated sheet thickness" in modeling the deck, it has pros and cons: pros being easier to model. cons that you are losing some extra stiffness due to overlap, and you are ignoring the extra weight of the overlapped region. My approach for this - if I want to be super accurate - is to model my deck using two thicknesses. One for a single thickness sheet (no overlap) and one with a double thickness sheet (yes overlap). Here I would have a small strip about the width of the beam/purlin or 1 corrugation in that sheet, this strip is to be modeled using double thickness. other regions are to be modeled using single thickness. Please note that I would think of this approach as being "too accurate", but in case your local/regional authorities demand such a degree of accuracy, then the approach above would be what I would follow. When you import your model into RSA, it will struggle importing the Z-sections and the corrugated sheet, because RSA has very limited abilities when it comes to the design of cold formed sections. I had a video explaining that problem during the "warehouse design series", so I guess that is the reason why the import seems to fail. I hope I addressed your questions. If I missed something, feel free to ask follow up questions. Thnx a lot and stay tuned for more content, CEE
@@CivilEngineeringEssentials "Thank you for your response, I understand my concerns about using different thicknesses and the challenges it can pose in accurately modeling the overlapping elements with both beams and shells connecting from node to node. It's unfortunate that when I converted my model from Advance Steel to RSA, the calculation didn't allow for overlapping. Defining a new section as a shell that behaves like a plate (corrugated steel sheet) rather than a beam can indeed be challenging in RSA. I defined a section for my corrugated steel sheet and imported it into RSA, but it behaved like a beam instead of a plate in the analysis. Given my specific job requirements to calculate deflection, bending moment, and stiffness of all plates or the rigid frame of plates due to various loads, including snow, wind, dead, live, and snowdrift loads for roofs with different heights, it's important to have a reliable tool that can handle overlapping and different thicknesses in different spans. Considering the complexity of my work and the specific materials I use (corrugated steel sheets as secondary beams with insulation, etc.), I'm wondering if RSA is the best tool for these tasks. It seems that RSA may not be well-suited for my type of work in industrial warehouses without concrete structures. Before making a decision, I plan to research and inquire about software options specifically designed for corrugated steel sheet analysis, as they might offer better functionality and accuracy for my needs. It's essential to choose a tool that aligns with the unique requirements of my projects, including the consideration of overlapping and varying thicknesses. Thank you for your insights, and I appreciate any further guidance or suggestions you may have.
Hi and thanks for ur content. Why moment of inertia of a section are different in RSA than Autocad or in Inventor, how can I get 100% correct Ix and Iy in RSA.
The way RSA calculates the inertias may be different. Especially when a section is not a circle. Take for example the polar moment of Inertia (J) used to calculate torsional stiffness. The paper that RSA uses to estimate this is: www.witpress.com/Secure/elibrary/papers/BE00/BE00010FU.pdf So those difference are to be expected.
@CivilEngineeringEssentials thanks for responding. My section is a corrugated steel deck, kind of trapezoid shape. I use Ix for span deflection, and Iy for support, no torsional analysis. Maybe you could make a video on how to calculate rigid diaphragm with metal deck on roof due to the lateral wind load. Stiffer and so on.
In that case, how do I change the alpha to 0 deg on principal system on section definition? In your example the alpha is 18.7 deg. By the way, thanks for the video
Hi there, thnx a lot for your comment. is it possible to give me the time-stamp that is related to your question so that I can refine my answer. As far as I understood, you are asking for the reason why the principal axis are rotated a certain way. Principal axis are sometimes shifted and rotated in such a way that provides "as far as possible" a double symmetry around the "shifted/rotated" axis. So it is automatically calculated. Still, if you provide a time-stamp that sparked your question, I would be able to further fine-tune my answer. Thnx a lot for your comment, Regards, CEE
Can this section properties tool be used to model and design RC beams as well? When we define this in the section definition it just gives steel as the material but not other materials like concrete or timber. Your thoughts?
Yes, even if you have steel as the material. You can go to: Geometry -> Properties -> Sections click on your defined section to edit it, and you could select from the drop down list the material type. Try that and tell me if it worked. I used this to define the AASHTO PCI girders for bridge engineering one time. Regards, CEE
Hi there, I just checked. It seems currently it is unavailable. I will search and see if I can find anything Link to the article: forums.autodesk.com/t5/robot-structural-analysis-forum/aluminium-design/m-p/7862044#M65250
Hello CEE, Thank for the tutorial videos on using RSA. However, I have a question regarding creating a built-up section. So, I encounter a case of a steel beam in which the T section is welded under I section. I use the "Section Definition" in RSA. However, when I analyze the section, the result seems inaccurate because it shows that the thickness of web and flange of that built-up section is Zero. Could you recommend on how to design that built-up section? Thank in advance.
if you do a stress analysis, it would be a mess because RSA would not "see" the various thicknesses in your section. It even messes up the deflection. I think I should make a follow-up video for that (Built up sections). It is a short-coming unfortunately. Regards, CEE
Hello, I have a problem with "self-made" steel profiles. During the calculations, I get an information "The following parameters of section %section_name% used in calculations are incorrect. ea, es". I am doing everything exactly as You do. What can cause this problem? Thank you for your help!
Here is a full article about it. There is a problem in the calculation of ea and es in some versions of RSA www.autodesk.com/support/technical/article/caas/sfdcarticles/sfdcarticles/The-following-parameters-of-section-section-name-used-in-calculations-are-incorrect-tw-tf-reported-while-section-steel-design-in-Robot-Structural-Analysis-2023.html This happened before to people. Check that out and tell me if it solved the issue. Regards, CEE
you can. Go to The Menu: Geometry -> Properties -> Sections then, select the section and edit it. when you edit it, you will see a menu just below the section name where you can select the material. hope it helps. CEE
It is better. As far as I know, Robot will still calculate the section correctly if you do not move to the 0,0. But I have seen some bugs in the 3D representation in older versions of robot when you open the "sections" view.
sorry mate but you did it all wrong, Z section is cold rolled section 1. When drawing in autocad you do not draw polyline but line ( centerline ) alone / the process you did is for solid section 2. When creating new section instead of new solid section you need to select new thin walled section 3. Take one of the existing cold rolled databases / copy rename it and delete existing profiles / then save your section there That way when analyzing the section it will be properly analyzed according to EN 1993-1-3
Hello CEE,
Thank you for this video, it has helped me a lot to kickstart a deeper dive into this subject especially with regards to defining custom cold formed sections (for roof purlins) with the goal to use these sections in the steel design module.
This is what I have found so far:
1. It seems that the design code that is currently implemented in Robot for the verification and design of THIN-WALLED cold formed sections is EN 1993-1-3
2. In the case where one intends to use their defined cold formed custom sections for design and verification in accordance with the code in #1 above; It is important to identify that custom section as a “THIN WALLED section”, this identification can be done during section definition or by “manually editing” the section database where the custom section was saved to. [see reference below]
Without the above explicit identification, Robot defaults to identify the sections created as ”SOLID SECTION”. Robot verifies and designs these “solid sections” in accordance to “normal steel design codes” such as the EN 1993-1-1 rather than with the cold formed sections design code in 1 above.
3. It is also possible to “copy, and then rename, and then edit as may be required” an existing section database that already contain cold formed sections on it. I prefer this method as it allows for a number of sections (with varying width, thicknesses, and heights, etc) to be available for the cold formed steel design module to select the more suitable section from during the design iterations. [see reference below]
I was able to do both (I created my own custom “thin-walled” cold formed sections and I copied and modified existing cold formed sections databases). I have also successful-ish ran the cold-formed sections verifications and designs according to EN 1993-1-3. However, I have hit the following snags that I am wondering if the CEE may be able to assist with:
4. No matter how I had defined a cold-formed section; when I run the “member verification” or “the code group design” I always get a message (more like a waring message) which says that:
“… the members are made from sections for which the EC3 code does not provide the formulas for calculating the critical moment. Mcr for these sections was calculated as for bisymmetric elements……”
This is driving me nuts because I can’t understand why EC3 for example would not have formulas for typical sections such as Z and C purlins [these are the sections that I am getting the warning message with]. Am I alone in this? what am I missing that is causing this message?
5. The “member verification” or “the code group design” is ONLY using the bending moment that is applied to the member to verify or to design the member, the shear force is NOT being brought in or imported to the member design calculations. I looked through the "configuration" settings on the design calculation dialog box but I could not find where to “tell robot” to design for both bending and shear.
Granted that it is possible to “manually” input the moment, shear, and even the axial force on the design results window although one would have to know the governing design cases for these pains ^_^ first in order to do this manual thing. I can’t understand why robot seem to be excluding the shear force in the purlin design? How can I ensure that both shear and moment (at the very least) are automatically imported from analysis to be used in the design module and calculations?
6. I have also noticed that the section “axes coordinate system for the section properties” that are being used with most [not with all, see reference] “thin-walled sections” databases seems to be the ones that assumes the sections’ horizontal and vertical axes co-ordinates system; the inclined principal axes coordinate system especially for the Z-section that was also mentioned by the CEE at 09:20 seem to be “ignored” by other databases … Given the analysis implications shown already by the CEE at 09:20 above, how significant is the omission from the design point of view of these Z-sections purlins in the case where the principal axes coordinate system is not taken as inclined?
References:
_www.autodesk.com/support/technical/article/caas/sfdcarticles/sfdcarticles/Robot-Steel-Design-How-to-code-check-a-member-of-Z-or-Sigma-shaped-thin-wall-section-according-part-3-of-code-NF-EN-1993-1.html
_www.autodesk.com/support/technical/article/caas/sfdcarticles/sfdcarticles/ROBOT-STEEL-DESIGN-how-design-user-defined-thin-walled-section.html
_www.autodesk.com/support/technical/article/caas/sfdcarticles/sfdcarticles/ROBOT-What-are-the-thin-wall-sections-catalogs-available-in-Autodesk-Robot-Structural-Analysis-Professional.html
I have enjoyed this video, it has sent me looking (the CEE way ^_^) I like what I have found, and I am looking forward to the next videos.
Keep well and kind regards, DK
Hi there Engr. DK,
just for your information, you just helped me out MASSIVELY!
I was doing some preliminary test on RSAP, and I missed this option! thanks a lot!!! you are the best and saved me some time in research
@@CivilEngineeringEssentials
Hello CEE,
Thank you for the feedback and for sharing your experiences.
It really makes me very happy to know that you have found this comment to be helpful. It is such an honor for me to be of assistance to you.
Your approach encourages me to “ask questions freely”, I enjoy our discussions and I find them to be very helpful and informative on many levels for me.
Kind regards, DK
1:13
For anyone who might come accross the problem I had: When saving the section to the User database 7:14 I had no database to select. Fix:
In RSA, go to Tools > Section Database: Create a new database "User" (in this case)
Then, in Job Preferences, under Databases > Steel and Timber sections, you add a new database and browse to the newly created previously ("User")
After that, the new database shows in the list 7:14 when adding new sections
I would like to take the oportunity to applaud the extra info from eng. Donald Khanye to an already informative video from CEE 👏
Great video, great series (Industrial Warehouses) and great channel!
Amazing tip!!! Thank you very much Eng. Razvan 👍👍🌹🌹
Thank you, your input save me a lot of headaches.
Hello CEE,
how do i model a tappered beam in Robot with a flat top.
Hi CEE,
It was a nice video, altough you can not calculate that in steel designing withouth a shape form definition.
You are right. I even stated all possible problems in the RSA cold formed steel design during my warehouse series. Unfortunately, Robot suffers in terms of designing cold formed sections. Here is the video for your reference:
ua-cam.com/video/kuwfiS6o0Bo/v-deo.html&ab_channel=CivilEngineeringEssentials
Thnx a lot for your comment, it helps a lot.
Regards,
CEE
I have three issue regarding these user defined sections:
-software doesn't do deflection check
-sometimes the section become rotated after insertion and the dimension doesn't match the one used in the AutoCAD
-Section is not seen in the database in the program data.
What could be the reason. Kindly assist
If you are doing custom sections, you lose a lot of RSA's abilities.
it is pretty unpredictable.
For the section not seen in the database, please make sure you select the "user specified"database, not a standard database such as AISC>
Regards,
CEE
Hello,
I want to express my gratitude for the fantastic learning content you provide on UA-cam. It has been incredibly helpful and enjoyable for me. I make it a point to watch one or two videos every day. 🙂
I primarily work with steel structures, such as purlins and corrugated steel sheets (Deck) without concrete and sandwich panels. I have a couple of questions:
Can I define my section as a shell instead of beams in the modeling software (presumably referring to the software "Robot")?
How do I define the overlapping of the plates (corrugated steel sheets) in Robot? Additionally, how can I calculate the stiffness of all plates together with stiffeners to account for wind loads?
Normally, I conduct all my designs in Advance Steel or Revit. However, the last time I attempted to transfer my model into Robot, it only recognized the main structure and not my Z purlins and corrugated steel sheets.
I would greatly appreciate your guidance on these matters. Thank you once again for your valuable content.
Hi there and thnx a lot for your comment. I am happy those vids help.
Sorry for the long response in advance, I try to elaborate as much as I can to help you and your fellow audience.
Ok, so first, defining the section of a beam as a shell:
Short answer: yes you can, but you lose RSA's abilities to design those section.
Long answer: yes you can, and each individual "plate" in your section becomes its own shell element. This is however, waaaay to much calculation effort, as you need to discretize your beam into tiny little pieces that would sky-rocket the calculation effort.
So, although it is a theoretical "yes", I do not recommend it.
As a secondary problem, you will lose any ability for robot to design that section for you.
You are dealing with corrugated sheets only as your decks. So no concrete nor sandwich. I want to re-iterate your question just to make sure I got this right:
So you are using corrugated sheets, which means that there is an overlap between two adjacent corrugated sheets, which happens usually on a beam/purlin element. Your corrugated sheets are overlapping because you want to "nail them" to the beam/purlin element. So, you are asking about how to model this deck.
Please note that: you could simplify and just use the "single corrugated sheet thickness" in modeling the deck, it has pros and cons:
pros being easier to model.
cons that you are losing some extra stiffness due to overlap, and you are ignoring the extra weight of the overlapped region.
My approach for this - if I want to be super accurate - is to model my deck using two thicknesses. One for a single thickness sheet (no overlap) and one with a double thickness sheet (yes overlap).
Here I would have a small strip about the width of the beam/purlin or 1 corrugation in that sheet, this strip is to be modeled using double thickness.
other regions are to be modeled using single thickness.
Please note that I would think of this approach as being "too accurate", but in case your local/regional authorities demand such a degree of accuracy, then the approach above would be what I would follow.
When you import your model into RSA, it will struggle importing the Z-sections and the corrugated sheet, because RSA has very limited abilities when it comes to the design of cold formed sections. I had a video explaining that problem during the "warehouse design series", so I guess that is the reason why the import seems to fail.
I hope I addressed your questions. If I missed something, feel free to ask follow up questions.
Thnx a lot and stay tuned for more content,
CEE
@@CivilEngineeringEssentials
"Thank you for your response,
I understand my concerns about using different thicknesses and the challenges it can pose in accurately modeling the overlapping elements with both beams and shells connecting from node to node. It's unfortunate that when I converted my model from Advance Steel to RSA, the calculation didn't allow for overlapping.
Defining a new section as a shell that behaves like a plate (corrugated steel sheet) rather than a beam can indeed be challenging in RSA. I defined a section for my corrugated steel sheet and imported it into RSA, but it behaved like a beam instead of a plate in the analysis.
Given my specific job requirements to calculate deflection, bending moment, and stiffness of all plates or the rigid frame of plates due to various loads, including snow, wind, dead, live, and snowdrift loads for roofs with different heights, it's important to have a reliable tool that can handle overlapping and different thicknesses in different spans.
Considering the complexity of my work and the specific materials I use (corrugated steel sheets as secondary beams with insulation, etc.), I'm wondering if RSA is the best tool for these tasks. It seems that RSA may not be well-suited for my type of work in industrial warehouses without concrete structures.
Before making a decision, I plan to research and inquire about software options specifically designed for corrugated steel sheet analysis, as they might offer better functionality and accuracy for my needs. It's essential to choose a tool that aligns with the unique requirements of my projects, including the consideration of overlapping and varying thicknesses.
Thank you for your insights, and I appreciate any further guidance or suggestions you may have.
Hi and thanks for ur content.
Why moment of inertia of a section are different in RSA than Autocad or in Inventor, how can I get 100% correct Ix and Iy in RSA.
The way RSA calculates the inertias may be different.
Especially when a section is not a circle.
Take for example the polar moment of Inertia (J) used to calculate torsional stiffness.
The paper that RSA uses to estimate this is: www.witpress.com/Secure/elibrary/papers/BE00/BE00010FU.pdf
So those difference are to be expected.
@CivilEngineeringEssentials thanks for responding. My section is a corrugated steel deck, kind of trapezoid shape. I use Ix for span deflection, and Iy for support, no torsional analysis.
Maybe you could make a video on how to calculate rigid diaphragm with metal deck on roof due to the lateral wind load. Stiffer and so on.
I think that is a great suggestion ^_^ I will keep it in mind.
In that case, how do I change the alpha to 0 deg on principal system on section definition? In your example the alpha is 18.7 deg. By the way, thanks for the video
Hi there, thnx a lot for your comment.
is it possible to give me the time-stamp that is related to your question so that I can refine my answer.
As far as I understood, you are asking for the reason why the principal axis are rotated a certain way.
Principal axis are sometimes shifted and rotated in such a way that provides "as far as possible" a double symmetry around the "shifted/rotated" axis.
So it is automatically calculated.
Still, if you provide a time-stamp that sparked your question, I would be able to further fine-tune my answer.
Thnx a lot for your comment,
Regards,
CEE
Can this section properties tool be used to model and design RC beams as well? When we define this in the section definition it just gives steel as the material but not other materials like concrete or timber. Your thoughts?
Yes, even if you have steel as the material. You can go to:
Geometry -> Properties -> Sections
click on your defined section to edit it, and you could select from the drop down list the material type.
Try that and tell me if it worked. I used this to define the AASHTO PCI girders for bridge engineering one time.
Regards,
CEE
Hi ! Can ve add Aluminium Section inside Steel reinforcement section ? I am designing aluminium façades sametimes ı need this
Hi there, I just checked. It seems currently it is unavailable. I will search and see if I can find anything
Link to the article:
forums.autodesk.com/t5/robot-structural-analysis-forum/aluminium-design/m-p/7862044#M65250
Hello CEE,
Thank for the tutorial videos on using RSA. However, I have a question regarding creating a built-up section. So, I encounter a case of a steel beam in which the T section is welded under I section. I use the "Section Definition" in RSA. However, when I analyze the section, the result seems inaccurate because it shows that the thickness of web and flange of that built-up section is Zero. Could you recommend on how to design that built-up section? Thank in advance.
if you do a stress analysis, it would be a mess because RSA would not "see" the various thicknesses in your section.
It even messes up the deflection. I think I should make a follow-up video for that (Built up sections).
It is a short-coming unfortunately.
Regards,
CEE
@@CivilEngineeringEssentials That video for composite section would be great.
Hello,
I have a problem with "self-made" steel profiles. During the calculations, I get an information "The following parameters of section %section_name% used in calculations are incorrect. ea, es". I am doing everything exactly as You do.
What can cause this problem? Thank you for your help!
Here is a full article about it. There is a problem in the calculation of ea and es in some versions of RSA
www.autodesk.com/support/technical/article/caas/sfdcarticles/sfdcarticles/The-following-parameters-of-section-section-name-used-in-calculations-are-incorrect-tw-tf-reported-while-section-steel-design-in-Robot-Structural-Analysis-2023.html
This happened before to people. Check that out and tell me if it solved the issue.
Regards,
CEE
Hello doctor , i have a little problem , the section is defined as concrete , how can i change the properties ?
you can. Go to The Menu:
Geometry -> Properties -> Sections
then, select the section and edit it.
when you edit it, you will see a menu just below the section name where you can select the material.
hope it helps.
CEE
@@CivilEngineeringEssentials Thank you.
thanks CEE! i would like to know do i always need to move my section's center of gravity to the coordinate 0,0 in CAD before saving it as .DXF?
It is better. As far as I know, Robot will still calculate the section correctly if you do not move to the 0,0.
But I have seen some bugs in the 3D representation in older versions of robot when you open the "sections" view.
sorry mate but you did it all wrong, Z section is cold rolled section
1. When drawing in autocad you do not draw polyline but line ( centerline ) alone / the process you did is for solid section
2. When creating new section instead of new solid section you need to select new thin walled section
3. Take one of the existing cold rolled databases / copy rename it and delete existing profiles / then save your section there
That way when analyzing the section it will be properly analyzed according to EN 1993-1-3