Iveco 90-16 Original Structure - remove triangle support beams?

[Kalle12]

Moin,

I am currently clearing out the remaining internal steel beams of the Iveco 90-16 box/structure.

Are the triangle support beams important for stability? Or can I safely remove those? I have attached a picture. The question is whether I can remove the 3 beams marked in orange, or not? I believe I have seen photos of completely cleared out 90-1-6 boxes before...

[hugepanic]

I have removed these 3 and I can easily stand on the roof with one person.

No worries, cut them out....

Someone said that roof is build to take the load of 8people, with the triangles.


Edit: the one strut in driving directions (x-direction) might be a little more critical for braking maneuvers. I have closed the sides of the structure, an all my x-loads from the roof can go there. So it depends on your other structures if you can follow my example.

[Kalle12]

I have removed these and I can easily stand on the roof with one person.

No worries, cut them out....

Someone said that roof is build to take the load of 8people, with the triangles.

That is great news. Have you noticed any twisting of the structure or other damage from offroading? Or can it handle the stresses of off-road without the triangles as well? I would think so considering the size of the steel beams and the number of them.

EDIT: I was planning to keep the one triangle in the x-direction, but really want to remove the two triangles for roof support (y-direction). I will have internal walls but I will not close the sides; the shutters will remain all around.

[meggmann]

With or without it will not stand offroad driving because the subframe is (or was if you have changed it) not made in a propper way to eliminate bending of the structure.
Nevertheless there is a secound Problem of the box, a steel frame is cover with aluminum sheets and fixed with rivets. Because of the difference in length gaining according to higher temperatures the rivets are loosen or broken.

Greetz Marcel

[Kalle12]

With or without it will not stand offroad driving because the subframe is (or was if you have changed it) not made in a propper way to eliminate bending of the structure.
Nevertheless there is a secound Problem of the box, a steel frame is cover with aluminum sheets and fixed with rivets. Because of the difference in length gaining according to higher temperatures the rivets are loosen or broken.

Greetz Marcel

I have used the truck in heavy offroading over the last two years and the structure has not bent or twisted anywhere. That includes hundreds of km on really terrible bumpy desert trails in Morocco. The subframe is original as far as I can tell with "spring mounts" in the front.

Regarding the aluminum sheets and rivets, they have so far lasted very well and nothing leaks or is loose. The truck is always outside in rain and sun alike.

I don't care if the structure breaks down over time since it is an original piece that I intend to replace sooner or later with a standing height box. However, I don't want to cut the triangles if they compromise the safety of the structure. For now I am just hoping to get feedback on this question while searching the forum for more clues.

[hugepanic]

From my feeling I would say it is OK to remove the struts if the roof is unloaded.
You can add some small 45° struts in the corners to reinforce against x-loads.

[Kalle12]

I would think x-loads through the side of the truck would be absorbed by the walls? But for x-loads in the driving direction 45° struts could be helpful? I am considering saving the big strut from the floor but removing the two others. The roof is loaded with the stock spare wheel, and a storage box in the opposite corner.

[hugepanic]

For definition:
X directions n is the forward driving/braking direction
Y is lateral (left/right)
Z is vertical (up/down)

To be save you can assume the the vertical struts can not effectively take any loads in x and y direction.

For y-loads you still have the sheet metal front and aft that will transfer loads from roof to the frame.

Foy x-loads you are missing this sheet metal. I would recommend to add a reinforcements like the one you want to remove.

[Kalle12]

Thanks for the explanation. So if I understand correctly, you are suggesting removing the struts that take the z force, but adding struts to absorb x force? Yes, for the y force I believe the sheet metal handles it. There are also horizontal struts that intersect the vertical struts in the front and rear wall.

[hugepanic]

Figure 1 shows the original condition
Figure 2 your cabin with removed strut
Figure 3 shows my proposal
Detail-A shows the high loaded area if you don't reinforce the structure

[Kalle12]

Thanks for a great drawing, I understand your explanation.

I have a question about the x force (driving direction) and reinforcements.

In the attached picture, the visible struts are how my truck has been for the last two years.

Did reinforcement for x force come from the blue strut, or the blue and green struts together? Perhaps I can safe some of the green struts and the blue strut in that case, and build around them.

[hugepanic]

If I see this right the green strut has been removed from left to center. The left-to-right part of the green strut (if left intact) reinforces the roof. It builds a triangle like in a house roof structure.
This triangle is now not intact, and can be removed intirely.

For x loads, only the blue strut is necessary.

[Kalle12]

If I see this right the green strut has been removed from left to center. The left-to-right part of the green strut (if left intact) reinforces the roof. It builds a triangle like in a house roof structure.
This triangle is now not intact, and can be removed intirely.

For x loads, only the blue strut is necessary.

Yes it's correct, the strut from left to center was removed and broke the bigger triangle. The right part was left intact as this was my old storage area. Now I'm removing the remainder of the green struts.

Regarding the broken large triangle, they still form two smaller triangles in the left and right corner and connecting in the center of the roof. Although weakened, wouldn't these smaller triangles still provide some roof support for z forces?