Autodesk Robot Structural Analysis

[#1]

I'm doing the code combinations with the automatic combinations option (EN 1990:2002 code).

First, I have to do them with the last option called "manual combinations-generate" because the previous options are not able to performance a non linear second order analysis. Is there any way to solve this, in order not to have a huge list of combinations and just have the ULS envelope?

Second, I only see the availability of making ULS combinations for the STR combinations of the code, what about the GEO and EQU combinations of this code??

Third, In my strucrure, I've already done some manual combinations, now I want to have the whole code combinations...I use this tool but, in the tab "cases" i just select the simple cases, and I ensure that the manual combinations are not selected, so then, why when I go to the "groups" tab I still have the combinations? I've opened the file in repair mode but this still happens.

[#2]

See the attached picture. You can generate combinations using two regulations of the same type and you can select the load cases you want to include as well as the combination types you want to generate. ACC includes seismic.

If you find your post answered press the Accept as Solution button please. This will help other users to find solutions much faster. Thank you.

[#3]

Which nature should I choose for the combinations? Does this nature affects in somewhere in a certain way?

[#4 · Accepted solution]

This is irrelevant unless you want to use one of these combinations in the definition of another combination and you care about the default load factor it should get.

If you find your post answered press the Accept as Solution button please. This will help other users to find solutions much faster. Thank you.

[#5]

Hi again,

Going over the combinations created automatically, I've noticed that something is not going correctly.

In the attached image you can see the EN 1990:2002 coeficientes, where for the cathegory H are empty, if empty box means 0 it would be ok...but I think it's working as if it would be 1.

when make the combinations, this loads of the H category have to be 0 when are acommpanying the leading action.

[#6]

what I mean is as shown in the following image.

LL E: Live load category E.

LL H: Live load category H.

When leading the LLE, the LLH souldn't be incluided in the combination as its acompanying factor is 0.

So the combination should be 1,35*DL1+1,5*LLE+0*1,5*LLH+0,6*1,5*W+0,5*1,5*S

[#7]

What is the difference of this two ways? The combinations are different.

[#8]

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LL E: Live load category E.

LL H: Live load category H.

When leading the LLE, the LLH souldn't be incluided in the combination as its acompanying factor is 0.

So the combination should be 1,35*DL1+1,5*LLE+0*1,5*LLH+0,6*1,5*W+0,5*1,5*S

In fact there should be two sets of ciombinatios and as far as I can see Robot creates them corerctly:

1. E is main load so we have 0 factor for H

1,35*DL1+1,5*LLE+0*1.5*LLH

2. H is main load and then E get 1

1,35*DL1+1,5*LLH+1*1,5*LLE

[#9]

The point is that Robot don't do what you and me agree:

Robot is doing this:

1. E is main load so we have 0 factor for H

1,35*DL1+1,5*LLE+1*1.5*LLH

2. H is main load and then E get 1

1,35*DL1+1,5*LLH+1*1,5*LLE

[#10]

Send me your file please.