Hello everybody.
I have a concrete slab that i would like to study and there is an embedded steel part inside the concrete. I have attached a screenshot of the model.
The embedded steel part is solid, not just the regular beam LINK180 parts. I made a cavity in the concrete slab, so the 2 parts...
I run a project of a large boat trailer consisting of 32 wheels.
Maximum load of the trailer will be 200 metric tonnes, so in theory each tyre should withstand 200/32 = 6.25 metric tonnes. At this rating i can easily find a tyre that fits into my dimension constraints.
However in practice, the...
Hello Erik,
I made a "hand" calculation of the pin, approximated as a beam. I applied N and mm as units anywhere to conclude in MPa (N/mm2).
Pin: D=60mm / Length=305mm
Section modulus = 21168mm3
Loads: Distributed load on each side of the pin, force on each side = -85.000N, length of load...
@Erik
"Not sure how the bushing is attached to the outer part, not the pin, but if it is pressed, perhaps a bonded contact between the outer part and the bushing might be a start there, of course, between the pin and the bushing the frictional contact is the most realistic there, and that seems...
Back again, now applying frictional contacts between the pin and the bushings, also between the hydraulic cylinder end with the pin.
Constraints
I applied a remote displacement (rotation x=0 all other free) on both sides of the pin, and also to the outer sides of each bushing insert...
This is the supporting structure of a large boat trailer. In the real world, the upper structure will rotate only a small amount until it is parallel to the inclined surface of the boat.
The pads of the upper structure should follow the inclination of the boat bottom sides, that why there is...
Hi David,
I have tried to raise the friction coefficient when applied frictional contacts but still no convergence.
How to add a rotational constraint? An how this could be realistic either?
Thanks!
One thought about the weird stress diagram. The stress results as shown above are for the whole pin, not for a specific node. As such, i suppose that maximum stress occurred at different nodes during the loading time period. So maybe due to stress redistribution, we had let's say point X with...
Based on these results, i attach a picture of the fatigue life.
Analysis Type: Strain Life
Mean Stress Theory: SWT
Stress component: Max Shear (this gives the worst result)
Fatigue life of 100.000 cycles is perfectly acceptable to my application, but something tells me that this is not a...
So, i am back with the final results.
Material model
http://oi65.tinypic.com/2ln9z47.jpg
Load case. Here i made a bit of a change, i added one second after the release of the force to give more time to the pin to come to its final steady state.
http://oi67.tinypic.com/2ia5x8i.jpg
Here is...
Hi again,
I have run a nonlinear analysis (large deflections on) but i could not use nonlinear contacts between the pin and bush because the angle of the acting force causes the structure to rotate so no convergence. I will try again though.
So what we have is "large deflections on", and...
@ Petr Vymlatil + L K
Many thanks for your replies.
I post again some images with corrected stress plot (370MPa).
I think the situation is quite serious as the whole circumference of the pin exceeds yield strength.
Section images also attached.
What do you think?
Would it be better to...
@ Petr Vymlatil
If i understand correctly, my fatigue analysis results are not correct just because the stress and strain i got from the linear static analysis are not correct either because the pin is outside the tensile strength limit.
@ L K
I attach some images from the analysis. I hope it helps.
I will try to decompose the area of interest and run a nonlinear analysis.
And yes, i have defined the full strain-life parameters of the material.
Strength coefficient: 920Mpa
Strength exponent: -0.106
Ductility coefficient...
I have used high quality and density hex mesh for the pin.
The contact with the bushing is "no separation" as this is dictated by the available computing resources. With my current workstation capabilities, nonlinear contact options will result in days of analysis time.
My analysis is linear...
Hello to all.
I am evaluating a project in terms of fatigue.
This is a large steel structure which is designed to take 40 tons of load.
I have done an analysis of 50ton just to be evaluate what will be the results in case the user loads the structure more than the specified maximum load...
Hello and thanks for your replies.
Yes, the title is a bit misleading. Wheel self-leveling system is how the system it normally called that's because i used it.
To maintain the bed level is a good thing but not absolutely necessary.
Anyway the bumps are not going to be large so the...