Steel Space truss design

[Mohamed Maher]

Dear all

anyone has design calculation for space 3d truss can share it with me, please.
is it the same as normal trusses or it needs a special requirement?
and the joint ball which is collecting the members(kindly refer to the attached, how we can design it?

Thanks
Maher

 

[hokie66]

Mohamed,

Space trusses are best left to proprietary suppliers. I wouldn't even attempt a one off system.

 

[HTURKAK]

-You may model the 3D space truss with FEM ( with using SAP 2000 or similar software ) assigning the joints free to rotate.

- But i will suggest you to ask the services of the supplier since this trade is specialized field and they provide design calc. when you choose as supplier..

- I remember collapse of HARTFORD CIVIC CENTER COLISEUM. Pls have a look to the following doc. to see the modelling issues..






If you put garbage in a computer nothing comes out but garbage. But this garbage, having passed through a very expensive machine, is somehow ennobled and none dare criticize it. ( ANONYMOUS )

 

[Settingsun]

SI base unit being kilogram instead of gram strikes again. Maybe being off by a factor of thousand on their allowable forces also contributed.

 

[hokie66]

steveh49,

Not sure what you mean. I don't think that SI units would have been involved at all in the 1970 design. If you mean those MN, GN forces listed in the article table, yes, the writers are confused about how SI is intended to be used. And yes, their conversions are off by a factor of 1000. Someone should tell them that units of force, for structural engineering purposes, should be expressed in kips in the US, kN elsewhere.

 

[Settingsun]

Just a joke because the SI values were presented as the main values, with US as conversions.

But I do suspect that using kg as the base unit, instead of g, confuses some people.

 

[hokie66]

They also get pressure units confused. Every engineer who tries to think across the unit divide should realize that that 1 kPa (not 1 Pa) is approximately 20 psf.

The authors of that paper should be ashamed, as should the editors. I suppose a correction is too difficult now, as the paper is more than 20 years old.

 

[dik]

and 4.8 of them is about 100 psf... if that helps.

-----*****-----
So strange to see the singularity approaching while the entire planet is rapidly turning into a hellscape. -John Coates

-Dik

 

[TLHS]

( with using SAP 200 or similar software )

My favourite.

 

[HTURKAK]

According to your post , although your favorite software is ABACUS , i am not sure if you can really use it ..But apparently you are capable with photoshop.

The original picture of the subject ABACUS is,

If you put garbage in a computer nothing comes out but garbage. But this garbage, having passed through a very expensive machine, is somehow ennobled and none dare criticize it. ( ANONYMOUS )