Load distribution to lighting column

[Anonymous]

Hi all,

I'm new to this forum, but I read a lot of useful comments in the forum.
I have a specific problem that I never anywhere could find an answer that would solve this problem. I download free trial version Robot Structural Analysis December 2016.

I press "Generate wind loads..." button and generate "x+" and "y+" wind direction. Wind in the direction of x + is in the "loads" shown in the "z" direction and I can not get relevant results bending moment. I have a lighting column height h = 4.0 m. In this I dont have the option of setting parameters such as the coefficient of exposure, distance from the sea, the coefficient of altitude, terrain category, shape coefficient...

The standard for lighting column is EN 40-5, and as input parameters have parameters contained in the "Wind and Snow 2D / 3D" (Standard EN 1991-1-3/4:2005). This option is perfectly suited as far as input parameters that I have, but it does not suit me because I MUST make "frame". I need a column, possibly with brackets for the lamp. I do not need frames at a spacing that make eg. "the hall".

My questions are:

1.) What type structure that I have to choose how I could choose "Wind and Snow 2D / 3D" and according to which standards?

2.) What program do you recommend for drawing holes in the column?

3.) According to the structural (EN 40-5), total bending moment is equal to M = sqrt(Mx^2+My^2). How to calculate that moment in RSA?

4.) What is the best method of setting the load when it comes to lighting column?

5.) I tried using the "cladding" but to no avail as the column has a small cross-section (d = 139.7 mm). "Cladding" must be completely flat in order to load could be transferred to the column. How to transfer the wind load on the column using the "cladding"?

6.) I need self weight factor and wind factor =1.2, instead 1.35 and 1.5 by default in RSA. Where is the place to adjust those factors?

7.) I get different results for forces on column, for example wind speed 20 m / s between the options "Wind and Snow 2D / 3D" and the "Generate wind loads ...". Option "Wind and Snow 2D / 3D "gives more greater forces than the second option.

I hope that you are able to understand the problems they've faced, and sorry for the bad English.

Please see the attachment.

Greeting,

Mario.

[Anonymous]

Does not anybody have answers to problems and questions? Without those answers, I can not properly calculate the static lighting columns. Please help.

Greeting,

Mario.

[Anonymous]

My problems that I encountered the oldest unanswered in the last few days. It's a bit strange for me. Are my questions so difficult that no one knows the answers to them? Or am I just impatient in waiting for a response? If someone still trying to find answers to my questions, I would like to write me a message.

Ty,

Mario.

[Rafacascudo]

- Wind X+ is on Z "local" direction of the bar. That´s how it is generated by cfd.

- "coefficient of exposure, distance from the sea, the coefficient of altitude, terrain category, shape coefficient" .

On Wind profile tab you set the it according to the wind standard you use.

1- http://forums.autodesk.com/t5/robot-structural-analysis/automatically-generated-snow-wind-loads-acco...

2-????

3-???

4-Sorry, What´s lighting collumm? Brazilian here. Couldn´t translate the meaning

5-Cladding is a "panel" without structural stiffness . It just distributes the load applied to it on bars or panel edges according to trapezoidal rule on 2 or just one direction. Your model has just one single bar. Don´t know how it would be useful.

6-Create manual combinations and use any factor you want

7-Can´t help you on this one. Never really used CFD  on a real project and there´s no brazilian wind code on RSA.

[Anonymous]

Rafacascudo thank you for response,

a) "lighting column" means a column on which is mounted lamp (lamp post). U know now what I mean? I dint know how better i can explain.

b) I did not use "CFD", but "Generate wind loads..."

c) Which is the best way to convey the speed of the wind on the pole? Wind will create some pressure on the pole.

d) The problem is that my column (pole) is not "frame" and I think it can not exercise the option "Wind and Snow 2D / 3D".

e) Can I change the local axes shall be equal to the global axes?

f) If I have a situation as shown in "picture1", I need the wind in "X" and "Y" direction (global), because it will give me the wind in one direction to create torsion on the pole in the other direction will not. Local axis of these 2 bars are different from each other.

g) Do you have any idea how to wind speed of eg 20 m / s convey the column, using the option "Wind and Snow 2D / 3D". I note that my column is not "frame".

h) "What program do you recommend for drawing holes in the column?" "holes in the column" mean "hole in a pole". I wanna draw hole in my pole (this is some kind of detail), then export into Robot. (from Structural Detailing, or Inventor, or...?)

Greeting,

Mario.

[Anonymous]

Please forgot questions under "e" and "f". I realized what's the point. Other questions still stand.

[Rafacascudo]

a-ok

b-CFD(Computational Fluid Dynamics) or generate wind loads are the same thing.They should give the same results

c-In this simple case I would calculate the wind load manually according to brazilian standards and apply it to the bar as any other bar linear load

e-Not always.Only when bar is on X global direction and section is a square or circular pipe( as the exposed area will be identical on both directions)

f-Don´t bother about the bar local direction. The load will  be generated on the correct perpendicular local direction. Loads on local bar direction are useful in case the bars are not in any of the 3 global axis directions.

h- If your intention is generate loads on this columm with holes,I don´t think it will be possible with a single bar member. MAybe with 2 bars for some section shapes like retangular.

Or you can do it using cladding with corresponding exposed area

[Anonymous]

Rafacascudo,

Thank you for explanations, but I have some concerns.

Maybe I was misled when it comes to the hole in the pillar. This hole is actually opening that serves to within pillars can connect cables, and opening later closed doors. The opening is located on one side of the pole.

May I take the "Wind and snow 2D / 3D" just to get pressure on the pole (kN/m2), but to make the frame (because for this option must be the frame) and later delete parts of the frame that I do not need and leave only column that I need, and then again to make a calculation of the wind load in kN / m2 on a pole?

Or can I use the "Wind load simulation ..." and with increasing coefficient for wind speed, to get the situation as I use the "wind and snow 2D / 3D" because I change the coefficient of wind speed could perhaps replace the odds that I have in "wind and snow 2D / 3D" (coefficient of exposure, terrain category, ...)?

Thanks in advance,

Mario.

[Artur.Kosakowski]

http://www.wikihow.com/Calculate-Wind-Load

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