structure analysis - suggestion

[pompeo79]

Bye to all,
I have a theoretical question for you and for those who deal with structural analysis.

I have a frame like that in figure. in reality it also has handkerchiefs (8 squares at 4 corners). by making the beam analysis you get the third picture in figure with its knots. Note that for the two external sides there are two beams per side.
to simulate the struttua with its forces as the first solution in mind (regardless of the analysis software, ) to simulate the contact between the two external beams per side could insert a rigid connection.

as a second solution I thought about simplifying everything by eliminating the external beams, the most extreme on the side.

with the idea of changing the mechanical physical characteristics of the two left ester beams in order to simulate their "double" resistance.
Could it work as an idea?
What feature do you suggest to change? Is the moment of ix inertia enough? and if you just double it?

Thank you very much in advance!:smile:

 

[gil]

Hi.
I don't know where the constraints are. Are the blue round balls? in the modified hypothesis, if you put the load at the center of the beams the slipping due to the eccentricity of the load is not simulated.

In my opinion, without entering the specific case, I suggest you remain as close as possible to reality. this is the beauty of the fem. otherwise for a very approximate verification, the residual tables of carpentry prontuaries are well.

 

[Betoniera]

how to evaluate double profiles in calculation simulations

the data you have transmitted shows that the profile in question is a hea 160, whose characteristics are:

profile type hea 160
area section af = cm2 38,77
elastic analysis
inertia axis x jx = cm4 1673
elastic resistance module x wx = cm3 220,1
inertia axis y jy = cm4 615,6
elastic resistance module y wy = cm3 76,95

with regard to bending for vertical loads
There is no doubt that the doubling of the profile involves the doubling of inertia.
Therefore, in the simulation, you can double all the data of the individual profile.

regarding simulation
if the model is simulated with a single shaft (doubled area and inertia) there are no problems. arrows and tensions will be correct.
if you simulate the double profile with two rods, then it is evident that the two rods are joined, otherwise the deformations of the two rods will be independent. so tensions and deformations will be wrong.

double profiles in some programs.
some calculation programs include the possibility of having double profiles.
I use structural robots where a single rod can be associated with double profile facilitating, so simulation.

Hello, next

 

[pompeo79]

thanks betoniera, you were exquisite.

In particular, I can only double the ix and iy inertia moments? tomorrow perhaps I can post the distribution of the loads. If you give me a few tips, I swear, toast, I owe you one!

 

[pompeo79]

Hi.
I don't know where the constraints are. Are the blue round balls? in the modified hypothesis, if you put the load at the center of the beams the slipping due to the eccentricity of the load is not simulated.

In my opinion, without entering the specific case, I suggest you remain as close as possible to reality. this is the beauty of the fem. otherwise for a very approximate verification, the residual tables of carpentry prontuaries are well.

Thank you very much gil. constraints have not yet been put. but are in correspondence of the knots