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Why doesnt BlenderBIM have Rebar ?

  1. O by Omeyotzin127 on 22 May 2024, edited 28 May 2024 #

    If this is a real BIM why doesn't have the option to generate Rebar ? i've seldomly seen any concrete without rebar, how do others that also use BlenderBIM in AEC generate and quantify rebar from their projects ? Good BIM includes structural elements and can quantify it... So you don't make a project with concrete and forget about rebar, hehehe... The video where it shows you how to make rebar with sverchok is just an alternative, hence its been forgotten in BlenderBIM.

    BIM is supposed to be a full composition of structural and representative elements of an AEC project.

    I am sorry if don't have the light of knowledge in me about this subject.

  2. T by theoryshaw on 23 May 2024 # +1 votes

    I can donate no problem, but when the Addon works right for architects.

    The solution is to improve the tool, so we can get more funding?

  3. O by Omeyotzin127 on 23 May 2024, edited 23 May 2024 #

    @paullee said:

    FreeCAD and IfcOpenShell (BlenderBIM used) has common 3D engine. Maybe there should be effort where development / code could be shared and speed up both development hopefully ?

    would be good

  4. O by Omeyotzin127 on 23 May 2024, edited 23 May 2024 #

    @theoryshaw said:

    @Omeyotzin127 What do you think the solution could be?

    Honestly, i dont code, but if i could contribute in that way i would, my contribution is saying the thruth about the way it works for me, im an architect in Mexico (just for background). I can donate no problem, but when the Addon works right for architects.

    What i think could be the solution is staying away from developing amenities for compatibilty between different applications, focusing on making a real functional BIM is better than instead sharing files between different software. For example they are developing making smart dxf to svg files, what is the good of this if the BIM Addon doesnt even compete with what all Architects need ? theres a saying for this:

    "Jack of all trades, master of none".

  5. M by Moult on 23 May 2024, edited 23 May 2024 # +4 votes

    I think you'll find that the development is heavily influenced by real world usecases. Almost everything developed is to solve a commercial problem that one or more users are facing. The most likely reason there isn't a rebar modeling tool (yet) is that the percentage of users who need it are very small, so given limited developer resource we haven't tackled it yet.

    This can be solved by either increasing developer resources (writing code, or funding), or by filing bug reports (so we get more accurate ideas about demand so we know where to allocate resources). There is already an existing bug report so I'd recommend adding a comment there, and after than helping contribute funding. $5 or $10 a month makes a big difference and adds up. We are hoping to hire another part time developer by the end of this year.

  6. M by Moult on 23 May 2024 # +3 votes

    I'd also like to say that the majority of BIM models do not contain any rebar modeling at all on commercial projects. It's only limited to the structural discipline (1 out of an average of 5-10 other models), and even then there are limited reasons why rebar is modeled. If it is modeled at all, it'll also happen during much later project phases, so most design development models will never contain rebar.

    Most of the time for quantity take-off purposes, using the ReinforcementVolumeRatio property is sufficient to know how much rebar is inside the concrete. This is typically shown on a schedule on a sheet as well.

    The exact rebar details are also typically 2D annotated. It's not critical to model it all in 3D. Some jobs do benefit greatly from 3D rebar, but it's not very common.

  7. T by theoryshaw on 22 May 2024 # +2 votes
  8. P by paullee on 22 May 2024 # +1 votes
  9. O by Omeyotzin127 on 22 May 2024 #

    @paullee said:

    With Native-IFC support with FreeCAD BIM/Arch, anyone tried to use Rebar/Reinforcement tools in FreeCAD to work with BlenderBIM?

    https://wiki.freecad.org/Arch_Workbench

    https://wiki.freecad.org/BIM_Workbench

    https://wiki.freecad.org/Reinforcement_Workbench

    Ive tried using FreeCAD before, only thing is that its rendering honestly is bad, and i tried continuing with Blender, but Blender lacks a lot of Architecture specific interface ease. I have not brought in any rebar from FreeCAD yet but like i said: im trying to stay away from jumping around to different software Applications, still not one better than those two private enterprise softwares we all know...

  10. O by Omeyotzin127 on 22 May 2024 #

    @theoryshaw said:

    There's no parametric tool currently, but you can create a profile based type, and assign it to IfcReinforcingBarType.

    ...

    Swept disks is also tantalizingly close, as an option, as well: https://github.com/IfcOpenShell/IfcOpenShell/issues/3496

    thank you, i will try working with the IfcReinforcingBarType meanwhile. But i really think its not a real BIM until one day when it has all features needed for an Architect, like i said sverchok is covering all lacks of BlenderBIM, my point of view is that it shouldn't be like that. Also CAD sketcher is not that great.

    Blender is a universal plattform that can shelter multiple addon applications, so its product is a blend of applications, i am aware that its opensource, but not saying the thruth about its funcionality and lack of ease in the workflow would make so many of us feel even more frustrated.

  11. P by paullee on 22 May 2024 #

    FreeCAD and IfcOpenShell (BlenderBIM used) has common 3D engine. Maybe there should be effort where development / code could be shared and speed up both development hopefully ?

  12. T by theoryshaw on 23 May 2024 #

    @Omeyotzin127 What do you think the solution could be?

  13. M by Moult on 23 May 2024 # +1 votes

    There is currently nothing developed for modeling rebar easily. In theory, the tools are there to do basic, highly manual rebar modeling, but it is nothing more than a start and insufficient for anything practical.

    Both FreeCAD and BBIM are using IfcOpenShell and IFC natively, so if we develop rebar modeling tools for one in native IFC, it'll automatically be shared with the other (apart from creating a UI). For example, FreeCAD gets an automatic standard case door generator for free :)

    If you'd like to help, the best way is to:

    1. Report bugs https://github.com/ifcopenshell/ifcopenshell

    2. Write code (same link)

    3. Contribute funding https://opencollective.com/opensourcebim

  14. O by Omeyotzin127 on 23 May 2024, edited 23 May 2024 #

    @Moult said:

    I think you'll find that the development is heavily influenced by real world usecases. Almost everything developed is to solve a commercial problem that one or more users are facing. The most likely reason there isn't a rebar modeling tool (yet) is that the percentage of users who need it are very small, so given limited developer resource we haven't tackled it yet.

    This can be solved by either increasing developer resources (writing code, or funding), or by filing bug reports (so we get more accurate ideas about demand so we know where to allocate resources). There is already an existing bug report so I'd recommend adding a comment there, and after than helping contribute funding. $5 or $10 a month makes a big difference and adds up. We are hoping to hire another part time developer by the end of this year.

    Ok, i understand a lot of "designers" don't use it, but architects do need it. My way of looking at this is that there a lot of people who upload videos related to BlenderBIM usage and modeling, and i can say that 95% of those videos are just 3D modeling with BIM (masses, volumes), but they are not using BIM for what BIM is intended for... BIM is intended for modeling realistic characteristics where Materials and Elements are the main Relevance of the model.

    Isn't it true that most call it BIM because it composes volumes called "walls", it composes volumes called "doors, windows, etc..", and this is the way they draw buildings and houses?. But BIM is about scheduling, BIM is about materials, quantities and sometimes physics when it comes to structural analysis, BIM is not about doing 3d modeling only, you dont need to use "BIM" to model anything that people model in those videos.

    "If you cannnot quantify all materials (EVERYTHING) in a BIM model then its just a partial project". So this is still more like a 3D volumetric sketcher.

    Composite columns are very common and they have rebar in their sleeves.

  15. M by Moult on 23 May 2024 # +2 votes

    You can quantify all materials - on our projects we most commonly use the ReinforcementVolumeRatio property for this rather than the overhead of modeling in 3D. This isn't specific to BBIM, most structural modelers (at least here in Australia) won't do 3D rebar unless there is no alternative.

    If you're looking for the definition of BIM, this is defined in ISO 16739-1, which is implemented by the BlenderBIM Add-on. If you're looking for capabilities more than 3D modeling, the features are demonstrated here:

  16. O by Omeyotzin127 on 23 May 2024, edited 23 May 2024 #

    @Moult said:

    I'd also like to say that the majority of BIM models do not contain any rebar modeling at all on commercial projects. It's only limited to the structural discipline (1 out of an average of 5-10 other models), and even then there are limited reasons why rebar is modeled. If it is modeled at all, it'll also happen during much later project phases, so most design development models will never contain rebar.

    Most of the time for quantity take-off purposes, using the ReinforcementVolumeRatio property is sufficient to know how much rebar is inside the concrete. This is typically shown on a schedule on a sheet as well.

    The exact rebar details are also typically 2D annotated. It's not critical to model it all in 3D. Some jobs do benefit greatly from 3D rebar, but it's not very common.

    Yeah, maybe in your country rebar is not relevant, in Mexico we use rebar and concrete in 85 % of all new buldings, homes, etc. Anyway, maybe its not really important, due to that we all may be using the wrong building construction system over here. I do know you do use rebar in all weight bearing slabs.

  17. M by Moult on 23 May 2024 # +1 votes

    I think you might be misunderstanding. We use rebar, we simply don't model it in 3D. We may model it in 2D, or we may simply have a non-geometric element with properties and relationships attached to it. Apart from the 3D modeling tools, which we're missing, we can do 2D rebar or non-geometric rebar data already in BBIM.

  18. O by Omeyotzin127 on 23 May 2024 #

    @Moult said:

    I think you might be misunderstanding. We use rebar, we simply don't model it in 3D. We may model it in 2D, or we may simply have a non-geometric element with properties and relationships attached to it. Apart from the 3D modeling tools, which we're missing, we can do 2D rebar or non-geometric rebar data already in BBIM.

    Thank you for your patience Dion, i wish i had the knowledge to compose a video related to rebar in the way of blender and its current resources... Best regards.

  19. O by Omeyotzin127 on 23 May 2024 #

    @theoryshaw said:

    The solution is to improve the tool, so we can get more funding?

    i know funding is meant to improve it, but theres no funding for this element. Thank you.

  20. E by emiliotasso on 23 May 2024 # +4 votes

    I've made an attempt with FreeCAD see https://community.osarch.org/discussion/2055/from-freecad-to-blenderbim-italian-house

    The Reiforcement workbench it's a very good starting point and seems to do what it promises, but i've found that is at a basic level to achieve a deliverable reinforcement ifc model.

    Of course my words depends on the Italian (European?) way of concrete designing, where the structural engineer is responsible to provide the construction detailing of the reinforcement.

  21. E by emiliotasso on 23 May 2024 # +4 votes

    From January the first 2025, in Italy BIM Ifc model will be mandatory for every public construction project over 1e+06 €. (so typically the structure cost will be 400 thousands €). I'm not experienced and skilled in BIM modeling, only two times i've created the 3Dmodel at Level of developement "C", and as @moult said I've modeled only concrete structure without reinforcement detailing (the rebar drawings were made via 2D cad as usual).

    There is some debate between small engineering firms about what will be the future with BIM modeling, personally I'm scared that public stakeholder will ask everything so also IFC rebar reinforcement will be mandatory. Typically in Italy engineering firms has 1,5 employer (including the boss!) so, apart from the trouble with learning the new metodology and a new software tool, there will be problem with the epensese' increase in software licensing.

  22. M by mcnill on 23 May 2024 # +3 votes

    From my point of view, you will not necessarily need reinforcement models to start and work with Bim workflows.

    Most times it'll be an exchange of building models and informations.

    In the last years bearly 1 or 2 BIM Pro asked for reinforcement models and didn't want to check them in the end.

    For sure this will change in the future and other may use them rightnow, That's just my experience...

  23. C by CSN on 23 May 2024 # +2 votes

    Not to add much into the discussion but I just want to say that for large civil works projects reinforcement IFCs are absolutely being used right now. For bespoke, irregular, non-standard concrete forms - they are a must have, in my opinion. These models are not just for reference, they are provided as design information, and used and seen by a huge range of disciplines on the projects.

    Whether or not BBIM needs to build itself into a powerful rebar modeller (ala Tekla) is up for debate though. I'm not a rebar designer/modeller, but I can't imagine it is overly simple. Easier to build the more basic and common parts first and then use those to build more complex systems. I'm still not 100% convinced that the slightly restricted customizability of Blender is enough to replace proprietary software in all cases, but now I'm waffling.

  24. M by mcnill on 23 May 2024 # +1 votes

    That's very interesting! In germany i've heard of very few projects where they used reinforcement IFCs as of now in infrastructure because of the complexer geometries.

    So we'll hopefully look into a brighter future!

    Personally i wouldn't work anymore with 2D based workflows. Espescially for reinforcement plans, but this is an old discussion ;)

  25. K by KoAra on 23 May 2024 # +2 votes

    I hear a lot about rebar and I know how hard it is to draw rebar with 2D CAD. On the other hand, should we model it into BIM? It is used in construction BIM, so it is useful in bidding and construction, but not in maintenance management for equipment replacement. Especially in terms of geometry. It might be used for computational analysis of earthquake resistance. I just don't see modeling rebar geometry as a higher priority than life cycle BIM and IoT utilization.

    Is ROI a term you would use at this time?

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