# Combination method for Load groups **URL:** \ **Category:** Grasshopper\ **Tags:** waiting\ **Created:** [9 January 2025 16:06 UTC](https://femdesign.discourse.group/t/combination-method-for-load-groups/438 "2025-01-09T16:06:28Z")\ **Posts on this page:** 20\ **Page:** 2
**Author:** ![Poja](https://dub1.discourse-cdn.com/flex017/user_avatar/femdesign.discourse.group/poja/32/305_2.png) [@Poja](https://femdesign.discourse.group/u/Poja)\ **Post date:** [17 January 2025 09:24 UTC](https://femdesign.discourse.group/t/combination-method-for-load-groups/438/21 "2025-01-17T09:24:03Z")
> [@MarcoPelle](#): > > Ehi @Poja > > It is a WIP and it might contains some bug (especially for custom load group combinations) > > However, I think you can use the following methodology to keep working in a full parametric environment > > ![image](https://europe1.discourse-cdn.com/flex017/uploads/femdesign_api/original/1X/388309c16ba6be7d2d9fff638357403bbe6c9954.png) > > The basic idea is: > > - create a .struxml file which will be a sort of template for you model > - read the file and create a model with `ReadFromFile` > - `AddElements` to the model will then add your parametric bridge geometry > > As LoadGroup are referencing some existing `LoadCase`, I think that you need to assign the existing `load case` to your loads using the one from Model.Deconstruct > > ![image](https://europe1.discourse-cdn.com/flex017/uploads/femdesign_api/original/1X/15a275abfc38e4dcd01053c5a89e20c1873828f4.png) I will try this now 😍 ❤ 👍 👍 👍 > [@MarcoPelle](#): > > You should use the following .gha tool to have the `Load relationship` bug fixed > > [FemDesign\_24.0.0\_WIP.zip](https://femdesign.discourse.group/uploads/short-url/mFI5K8XLfbPqlvzDTLSO4oMvyEs.zip) (1.2 MB) Thanks, which bug does it fix? I still have this issue for permanent loads not being able to be alternative. Is the WIP intended for this, or some other bug? Maybe I did not install it correctly… ![image](https://europe1.discourse-cdn.com/flex017/uploads/femdesign_api/original/1X/1b24a322ae87e3a4dd818c38d3f0de1fc46ae529.png) ---
**Author:** ![MarcoPelle](https://dub1.discourse-cdn.com/flex017/user_avatar/femdesign.discourse.group/marcopelle/32/6_2.png) [@MarcoPelle](https://femdesign.discourse.group/u/MarcoPelle)\ **Post date:** [17 January 2025 09:45 UTC](https://femdesign.discourse.group/t/combination-method-for-load-groups/438/22 "2025-01-17T09:45:02Z")
For anything related to LoadGroup which does not currently work, you currently have to use the “readfromfile” methodology that I have show above. The LoadGroup component that you currently have will be rewritten in the next month. Basically, no load group components in your grasshopper script. You will get those from the Model.ReadFromFile as they are inside the .struxml file that you will load ---
**Author:** ![Poja](https://dub1.discourse-cdn.com/flex017/user_avatar/femdesign.discourse.group/poja/32/305_2.png) [@Poja](https://femdesign.discourse.group/u/Poja)\ **Post date:** [17 January 2025 10:32 UTC](https://femdesign.discourse.group/t/combination-method-for-load-groups/438/23 "2025-01-17T10:32:02Z")
I have not managed to run your suggestion fully yet, but I understand it well. But I am excited to look into the struxml-file for the first time, very interesting how this works 🤩!!! So basically, the GH-components generate text in the struxml-file at the end of the day? So, the reason I think your suggestion will not help me fully is that changing my structure will also change the number and names of load-cases as well as the position and number of loads. A new template would have to be saved each time. However, I wounder about these GUID values… what are these? Do they need to be in those formats or can I choose whatever unique value I want? I’m thinking if it would be possible to create these custom load case realationships by just adding them into the struxml-file via a python-component i GH? That would be beautiful 🥹 ![image](https://europe1.discourse-cdn.com/flex017/uploads/femdesign_api/original/1X/09f9006849e4f16c4219a24a38b8836cbbbf5cc9.png) ---
**Author:** ![MarcoPelle](https://dub1.discourse-cdn.com/flex017/user_avatar/femdesign.discourse.group/marcopelle/32/6_2.png) [@MarcoPelle](https://femdesign.discourse.group/u/MarcoPelle)\ **Post date:** [20 January 2025 11:27 UTC](https://femdesign.discourse.group/t/combination-method-for-load-groups/438/24 "2025-01-20T11:27:06Z")
> [@Poja](#): > > So, the reason I think your suggestion will not help me fully is that changing my structure will also change the number and names of load-cases as well as the position and number of loads. A new template would have to be saved each time. My suggestion should actually help as the geometry is detach from the LoadGroup. However, as the load that you will apply to your model are linked to load cases, and the load cases are linked to the load group, you need to use the load cases from the `template file`. > [@Poja](#): > > However, I wounder about these GUID values… what are these? Do they need to be in those formats or can I choose whatever unique value I want? I’m thinking if it would be possible to create these custom load case realationships by just adding them into the struxml-file via a python-component i GH? That would be beautiful 🥹 The custom relationship can be created in the `template` file. I have solved temporarily an issue related to the `LoadGroupDefinition` in the following .dll Have a look at the attached example. It should be self-explanatory for you 🙂 [LoadGroup\_example.zip](https://femdesign.discourse.group/uploads/short-url/v9B4puXguNcn6i7LrqSIcDcon58.zip) (61.2 KB) [FemDesign\_24\_0\_0.WIP\_2.zip](https://femdesign.discourse.group/uploads/short-url/cQqtolWxqKrAHycOtktt97oW3t8.zip) (1.2 MB) ---
**Author:** ![Poja](https://dub1.discourse-cdn.com/flex017/user_avatar/femdesign.discourse.group/poja/32/305_2.png) [@Poja](https://femdesign.discourse.group/u/Poja)\ **Post date:** [20 January 2025 11:50 UTC](https://femdesign.discourse.group/t/combination-method-for-load-groups/438/25 "2025-01-20T11:50:43Z")
Thanks Marco! In my GH-script, changin the length of the bridge changes the number of load cases. I also managed to find a quite good (temporary) work-around during this week-end which allows me to solve my current issues without having to define custom relationships! ---
**Author:** ![MarcoPelle](https://dub1.discourse-cdn.com/flex017/user_avatar/femdesign.discourse.group/marcopelle/32/6_2.png) [@MarcoPelle](https://femdesign.discourse.group/u/MarcoPelle)\ **Post date:** [29 January 2025 10:38 UTC](https://femdesign.discourse.group/t/combination-method-for-load-groups/438/26 "2025-01-29T10:38:13Z")
Hej @Poja , @Bohman Can you give some comment on the workflow? ![image](https://europe1.discourse-cdn.com/flex017/uploads/femdesign_api/original/1X/54bef513f4a03733c26a0748f0f0f6705e901309.jpeg) is it helpful to have also a “number” in the `data` input? ![image](https://europe1.discourse-cdn.com/flex017/uploads/femdesign_api/original/1X/bd52a7fe6c6da2f78d24954f10bddebe054fc33b.jpeg) ---
**Author:** ![Bohman](https://dub1.discourse-cdn.com/flex017/user_avatar/femdesign.discourse.group/bohman/32/16_2.png) [@Bohman](https://femdesign.discourse.group/u/Bohman)\ **Post date:** [29 January 2025 11:49 UTC](https://femdesign.discourse.group/t/combination-method-for-load-groups/438/27 "2025-01-29T11:49:35Z")
Very happy to see this being added!! Regarding the workflow: It will be very time consuming to produce all those “combination-rules-rows”, and keep track of them. Especially when dealing with many loadgroups, it might get a bit messy. But I don´t have any better solution atm so I would still prefer this over nothing. The **most important** part for me would be to first add the option of adding predefined combinations (the button “Add combinations” in the GUI). In this way I can override the national annex (EKS for me working with bridges in Sweden) ---
**Author:** ![MarcoPelle](https://dub1.discourse-cdn.com/flex017/user_avatar/femdesign.discourse.group/marcopelle/32/6_2.png) [@MarcoPelle](https://femdesign.discourse.group/u/MarcoPelle)\ **Post date:** [29 January 2025 13:25 UTC](https://femdesign.discourse.group/t/combination-method-for-load-groups/438/28 "2025-01-29T13:25:40Z")
gotcha! I will open a ticket for our developers. Unfortunately, .struxml does not have access to the functionality and it will need some low level code. However, you can expect to have all the other settings ready to be use! ---
**Author:** ![Poja](https://dub1.discourse-cdn.com/flex017/user_avatar/femdesign.discourse.group/poja/32/305_2.png) [@Poja](https://femdesign.discourse.group/u/Poja)\ **Post date:** [30 January 2025 05:58 UTC](https://femdesign.discourse.group/t/combination-method-for-load-groups/438/29 "2025-01-30T05:58:28Z")
Agree with @Bohman , I would prefer an easy way to choose from the existing combination rules so I can pick 6.10a&6.10b instead of EKS. Of course, customization is also necessary! Much more importantly is the subgroups! Edit: Do you plan to implement a “Deconstruct” component for load group combination? That would be essential if one needs to change something from the existing combionations. In my case, If I would want to exclude a load group from getting combined with another group. I would make an easy component for the user, to just check which loads should not occur simultaneously! ---
**Author:** ![MarcoPelle](https://dub1.discourse-cdn.com/flex017/user_avatar/femdesign.discourse.group/marcopelle/32/6_2.png) [@MarcoPelle](https://femdesign.discourse.group/u/MarcoPelle)\ **Post date:** [11 February 2025 11:37 UTC](https://femdesign.discourse.group/t/combination-method-for-load-groups/438/30 "2025-02-11T11:37:46Z")
@Poja @Bohman I have just realised an updated version of LoadGroup. Unfortunately, we haven’t had time to implement the subGroup but they might follow in the next milestone. ---
**Author:** ![Poja](https://dub1.discourse-cdn.com/flex017/user_avatar/femdesign.discourse.group/poja/32/305_2.png) [@Poja](https://femdesign.discourse.group/u/Poja)\ **Post date:** [14 February 2025 07:33 UTC](https://femdesign.discourse.group/t/combination-method-for-load-groups/438/31 "2025-02-14T07:33:38Z")
> [@MarcoPelle](#): > > realised an updated version of LoadGroup. Unfortunately, we haven’t had time to implement the subGroup but they might follow in the Great, thanks! I will have a look at it soon! ---
**Author:** ![Poja](https://dub1.discourse-cdn.com/flex017/user_avatar/femdesign.discourse.group/poja/32/305_2.png) [@Poja](https://femdesign.discourse.group/u/Poja)\ **Post date:** [23 April 2025 11:34 UTC](https://femdesign.discourse.group/t/combination-method-for-load-groups/438/32 "2025-04-23T11:34:40Z")
Hi @MarcoPelle ! Have we gotten any sub-group functionality yet? ---
**Author:** ![anLor](https://avatars.discourse-cdn.com/v4/letter/a/aca169/32.png) [@anLor](https://femdesign.discourse.group/u/anLor)\ **Post date:** [7 May 2025 15:21 UTC](https://femdesign.discourse.group/t/combination-method-for-load-groups/438/33 "2025-05-07T15:21:46Z")
Hi Poja! 👋 Unfortunately, subgroups have not been added to the API yet. It is still on the to-do list. ---
**Author:** ![MarcoPelle](https://dub1.discourse-cdn.com/flex017/user_avatar/femdesign.discourse.group/marcopelle/32/6_2.png) [@MarcoPelle](https://femdesign.discourse.group/u/MarcoPelle)\ **Post date:** [29 December 2025 16:25 UTC](https://femdesign.discourse.group/t/combination-method-for-load-groups/438/34 "2025-12-29T16:25:16Z")
@Bohman @Poja ![image](https://europe1.discourse-cdn.com/flex017/uploads/femdesign_api/original/1X/0f1e76d0dfc3323c7066e445602f34bccfe366d3.png) Something is moving related to the topic. The `Custom` method is pretty large and, based on the conversation I had with you, I came up with a solution that it is pretty flexible and should help you most of the time. The main idea is that you can modify the combination group table using text format and FEM-Design will read it. In that way, you will be able to modify/create the .csv programmatically if you want (but you do not have to) and modify the values as you preferred. It is currently the best solution that we can offer (especially thinking that we are inside Grasshopper) 🙂 ---
**Author:** ![Bohman](https://dub1.discourse-cdn.com/flex017/user_avatar/femdesign.discourse.group/bohman/32/16_2.png) [@Bohman](https://femdesign.discourse.group/u/Bohman)\ **Post date:** [4 January 2026 08:33 UTC](https://femdesign.discourse.group/t/combination-method-for-load-groups/438/35 "2026-01-04T08:33:51Z")
Great, looks lika a reasonable workaround for now ---
**Author:** ![Arun\_N\_Dinesh](https://avatars.discourse-cdn.com/v4/letter/a/dbc845/32.png) [@Arun\_N\_Dinesh](https://femdesign.discourse.group/u/Arun_N_Dinesh)\ **Post date:** [5 June 2026 14:44 UTC](https://femdesign.discourse.group/t/combination-method-for-load-groups/438/36 "2026-06-05T14:44:25Z")
Hi @MarcoPelle Adding to this thread if its relevant. Is the “LoadGroupTable.Construct” component is released? 1. In my case I wish to Generate load combination with the load groups of moving vehicle loads as well. Is it possible? 2.Furthermore, since the vehicle load is generated automatically only after the FEM model is opened or run, I am unsure how to create a load group for the moving vehicle load in GH and link it to the load group below for generating load combinations. ![image](https://europe1.discourse-cdn.com/flex017/uploads/femdesign_api/original/2X/f/fc59413adf2351acfaac9c973bfa88b93d9be186.png) ![image](https://europe1.discourse-cdn.com/flex017/uploads/femdesign_api/original/2X/7/7f03a27711e49efacb901fd975c4dfc4a64baa4c.png) ---
**Author:** ![MarcoPelle](https://dub1.discourse-cdn.com/flex017/user_avatar/femdesign.discourse.group/marcopelle/32/6_2.png) [@MarcoPelle](https://femdesign.discourse.group/u/MarcoPelle)\ **Post date:** [10 June 2026 13:56 UTC](https://femdesign.discourse.group/t/combination-method-for-load-groups/438/37 "2026-06-10T13:56:13Z")
Hi @Arun_N_Dinesh The LoadGroupCombinations table is still under development. The idea will be to fully rely on the software functionality. From a user point of view, it will only be a “SetCustomCombinationMethod”. ---
**Author:** ![Bohman](https://dub1.discourse-cdn.com/flex017/user_avatar/femdesign.discourse.group/bohman/32/16_2.png) [@Bohman](https://femdesign.discourse.group/u/Bohman)\ **Post date:** [2 October 2026 08:19 UTC](https://femdesign.discourse.group/t/combination-method-for-load-groups/438/38 "2026-10-02T08:19:24Z")
Any new on the custom combination tool for load groups in grasshopper? ![image](https://europe1.discourse-cdn.com/flex017/uploads/femdesign_api/original/2X/2/218f2dc97a9e63770a07b44c4ba3a9d73f6578bb.png) ---
**Author:** ![MarcoPelle](https://dub1.discourse-cdn.com/flex017/user_avatar/femdesign.discourse.group/marcopelle/32/6_2.png) [@MarcoPelle](https://femdesign.discourse.group/u/MarcoPelle)\ **Post date:** [5 October 2026 07:42 UTC](https://femdesign.discourse.group/t/combination-method-for-load-groups/438/39 "2026-10-05T07:42:13Z")
Ehi @Bohman Unfortunately, not yet. It is still one of our priority but, due to a major refactoring, the task is still not solved. ---
**Author:** ![Bohman](https://dub1.discourse-cdn.com/flex017/user_avatar/femdesign.discourse.group/bohman/32/16_2.png) [@Bohman](https://femdesign.discourse.group/u/Bohman)\ **Post date:** [5 October 2026 07:55 UTC](https://femdesign.discourse.group/t/combination-method-for-load-groups/438/40 "2026-10-05T07:55:57Z")
@MarcoPelle Right, is it possible to script a workaround with the c# core or by using any other method? [Previous page](https://femdesign.discourse.group/t/combination-method-for-load-groups/438.md?page=1) [Next page](https://femdesign.discourse.group/t/combination-method-for-load-groups/438.md?page=3)