Edge load (API)

[stathiseleftheriadis]

Hi,

Is there a way to assign a linear load on a single edge (29_Edge(4) or a selection of slab edges with the API? 

Thanks

[Romanich]

As far as I know it is not possible to select a single edge like 29_Edge(4) via API.

[stathiseleftheriadis]

Thanks

Initially, I thought it can be done like this

SDL = (RobotSimpleCase)Robapp.Project.Structure.Cases.Get(10);
// int IL_B = CaseIL.Records.New(IRobotLoadRecordType.I_LRT_UNIFORM);
LoadRecord = (RobotLoadRecord)SDL.Records.Get(1);
LoadRecord.SetValue(System.Convert.ToInt16(IRobotLinearOnEdgesRecordValues.I_LOERV_PX), 0);
LoadRecord.SetValue(System.Convert.ToInt16(IRobotLinearOnEdgesRecordValues.I_LOERV_PY), 0);
LoadRecord.SetValue(System.Convert.ToInt16(IRobotLinearOnEdgesRecordValues.I_LOERV_PZ), -1500);
LoadRecord.Objects.Add(EdgeSelection);

But I'm struggling to get the selection of edges. 

I event tried 

 LoadRecord.Objects.AddText("29_(4)");

But it's not working

[Rafal.Gaweda]

Hi @stathiseleftheriadis 

Roman is right. It is not implemented in API.

[stathiseleftheriadis]

Thanks Rafal. 

So as an alternative I'm creating small edge panels around the slab with height similar to slab thickness and then I apply FE Uniform load to those (which can be done in API). Do you think that would yield similar results?

[Rafal.Gaweda · Accepted solution]

Dear @stathiseleftheriadis

Exactly !

See example:

https://forums.autodesk.com/t5/robot-structural-analysis-forum/error-2110-problem-with-linear-loads/...

But you may encounter this:

Objects not assigned to record if macro used more than one time on opened Robot

[stathiseleftheriadis]

Great. So far I haven't encountered any issues. I'm running it on a recursive algorithm in a case study with balcony loads. I run a test with more than 500 simulations and it was OK. 

My only concern was the edge stiffness benefit due to the thickness of the panel but I reckon it would be minimal. 

[Anonymous]

Hi @stathiseleftheriadis and @Rafal.Gaweda,

Nice work around to solve the problem. I can create these edge panels along the boundary of the slab, but shouldn't I keep the thickness of these edge panels as less as possible ? Why did you take their thicknesses as equal to the thickness of the base slab?

[Anonymous]

hi @stathiseleftheriadis and @Rafal.Gaweda, I am looking to apply my linear load on these edge panels. 

[Rafal.Gaweda]

Hi @Anonymous

As @Romanich mentioned - fake bars there or add lines there and apply loads to them

[Anonymous]

Hi @Rafal.Gaweda

str.Nodes.Create(1, 0, 0, BaseLevel + WallHeight);
str.Nodes.Create(2, 0, B, BaseLevel + WallHeight);
str.Nodes.Create(3, W, B, BaseLevel + WallHeight);
str.Nodes.Create(4, W, 0, BaseLevel + WallHeight);

str.Bars.Create(1, 1, 2);
str.Bars.Create(2, 2, 3);
str.Bars.Create(3, 3, 4);
str.Bars.Create(4, 4, 1);

/Apply dead load of roof slab

RobotSimpleCase deadweight_roof = str.Cases.CreateSimple(5, "Dead weight of roof", IRobotCaseNature.I_CN_PERMANENT, IRobotCaseAnalizeType.I_CAT_STATIC_LINEAR);
deadweight_roof.Records.New(IRobotLoadRecordType.I_LRT_UNIFORM);
IRobotLoadRecord2 LoadRec4 = deadweight_roof.Records.Get(1) as IRobotLoadRecord2;

LoadRec4.SetValue(2, -2000);
LoadRec4.SetValue(11, 1);
LoadRec4.Objects.FromText("1,2,3,4");

This doesn't throw an error. But it doesn't reflect the loading either. I am unable to figure out where I have gone wrong

[Rafal.Gaweda]

Hi @Anonymous

Use :

LoadRec4.Objects.FromText("1 2 3 4");

instead of 

LoadRec4.Objects.FromText("1,2,3,4");

[Anonymous]

It doesn't work 😞

[Anonymous]

Is it because I haven't initialised the bars?

[Rafal.Gaweda]

Hi @Anonymous

Try : 

RobotLoadRecord LoadRec4 =....

[Anonymous]

Hi @Rafal.Gaweda,

Thank you for your reply. But it still doesn't work. 😞

[Anonymous]

I found the bug. It should be I_LRT_BAR_UNIFORM  and not I_LRT_UNIFORM.

[Anonymous]

Hi @Rafal.Gaweda and @Romanich,

How do I assign properties to the bars so that the overall effect on my calculations is minimum? (since the bars shouldn't technically be there in the first place). Any suggestions are welcome

[Anonymous]

Hello,

I am facing the same problem. Can you please share me how you added the edge in your code ..