Good question. The solutions I was presented with at the time did not have that solution but two-part lids.Violina said:
So the title and the film (only showing half the lid) from the company say they make 8x4m as TS wants it (I haven't delved deep into their catalog), but based on the steel dimensions presented here, I strongly doubt that's accurate.
If it is accurate, then it's some form of monster construction in a truss on the far long side. The short side with a span of just over 4m shouldn't be any issue. But aluminum with a span of over 8m! Hopefully, they have a patent on that solution…..
If it is accurate, then it's some form of monster construction in a truss on the far long side. The short side with a span of just over 4m shouldn't be any issue. But aluminum with a span of over 8m! Hopefully, they have a patent on that solution…..
Probably because they don't make that type of cover for this size of pool.Huggedugge1 said:
Otherwise, they would have presented it to you??
Anyway, I would say you won't solve your current construction in a smooth and easy way at all, it will unfortunately have to be quite heavy.
And that's because the span is so large and the construction itself is heavy.
Can you fit a pipe along the length in the middle as well, or just one at the end?
Does it have wheels in the middle on the long side that doesn't hang over the pool?
Yes, your reasoning sounds logical. But how do I reinforce it if not with steel? Or aluminum?richardtenggren said:
The problem for you is the long span, a better design would have been to let the deck run along the long side. That way the construction would have been much sleeker, but maybe that wasn't possible in your case. If you study the formula for deflection as it is, you'll see that the length is expressed in cubic, which means that the deflection is greatly affected by an increase in length.
I would also check the foam, it really looks like EPS and not XPS, as previously mentioned it's irritating to calculate on the wrong grounds
If I had been given this task, I would have probably presented two solutions for the customer;
The first with sufficiently high profiles so that the construction could handle the free length even with a reasonable surface load (since I assume it should act as a deck when closed, exposed to snow, etc.).
The second option is to design the construction so that the deck can handle its own weight, but in the closed position, the longitudinal beams are supported by the underlying structure. Thus there is one or more extra supports and it is the length of the short side that should handle the surface load from people and snow.
For the surface load, it's probably sufficient to design for the snow load, as these rarely exist simultaneously, but someone in construction/architecture could probably answer that.
I guess the customer chose the second solution as it probably became much cheaper.
As I said, I can tear the whole thing down and keep the decking. Replace the frames with steel and the framework with load-bearing sheet metal.
But what material and what dimensions?
Surely good with bent pipes, etc., but which sheet metal worker has machines that can handle that in those dimensions?
I don't think Aqvisdeck has done so...
Either you familiarize yourself with how to calculate this kind of thing or you pay someone to do it.
I have no great desire to try and help someone calculate and construct this type of thing based on incomplete information.
Better to buy from that decking company now then (if you are okay with redoing the construction) since they now offer the cover you should have???
Because it will neither be cheap nor easy to solve on your own.
Best regards, "the one who can both calculate, design, and manufacture this type of construction"
There are rail wheels on the rear side as well. In total, I've placed 5 rails with wheels.
If I take off the decking, I can get anything into the construction.
They didn't have the model shown in the video when I was in contact with them. But as you can see in the video, they have it now - with the same dimensions I need. Seems to work really well.
Regardless, I can tear everything down if it can't be fixed with the existing. But I still need to know the dimensions and materials needed...
Yes, maybe I would have done that if I didn't have what I have today. Which is why I've been looking for solutions to the problems here in the group.
Cool that you know this! I don't, which is why I'm asking.
Well… I'd like to solve it with the resources I have now. Otherwise, their lid costs about 165-200KSEK, and then it would be smarter to try to fix the existing deck, wouldn't it? If you can find someone who can provide a concrete proposal on material and dimensions.
What's fun is that I've received many good comments in the thread.
The long span is, as mentioned, crucial to the problem. As mentioned, the length is cubed in the calculation. If you also consider that the self-weight increases proportionally with the length, the deflection becomes proportional to the length raised to the power of 4. So with double the span, the deflection increases by a factor of 8.
Another problem with the current state is that it's a bit like pick-up sticks. There are several beams that are not continuous between their supports but contain joints, cut with another beam passing through, etc. Such joints become somewhat like hinges if they are not made moment-stiff and cause further deflection.
I won't be presenting a complete solution for the entire roof that I can guarantee will solve all the problems but am happy to help with insights and assessments. Considering that it will cost quite a bit no matter how you proceed, it might be worth hiring a structural engineer.
I'll think about it a bit more, but first, time for dinner
Another problem with the current state is that it's a bit like pick-up sticks. There are several beams that are not continuous between their supports but contain joints, cut with another beam passing through, etc. Such joints become somewhat like hinges if they are not made moment-stiff and cause further deflection.
I won't be presenting a complete solution for the entire roof that I can guarantee will solve all the problems but am happy to help with insights and assessments. Considering that it will cost quite a bit no matter how you proceed, it might be worth hiring a structural engineer.
I'll think about it a bit more, but first, time for dinner
In the meantime, while @Bernieberg is recharging, may I ask how you have solved the motor drive and if you have any link to the tracks?
D Derbyboy said:
D Derbyboy said:
https://umakovshop.com/bottom-guiding-rail-u-inox-l-6000-mm-5fb0568a29f6f4001b840c75Bernieberg said:
The long span is, as I mentioned, crucial for the problem. As mentioned, the length is cubed in the calculation. If you also consider that the weight increases proportionally to the length, the deflection becomes proportional to the length to the power of 4. So with double the span, the deflection increases by a factor of 8.
Another problem with the current setup is that it's a bit like a pick-up-sticks game. There are several beams that are not continuous between their supports but contain joints, cut with another beam passing through, etc. Such junctions act as hinges if not made moment-stiff and contribute to further deflection.
I will not present a complete solution for the entire roof that I guarantee solves all problems, but I'm happy to help with inputs and assessments. Considering it costs a bit however you proceed, it might be worth hiring a designer.
I'll think further, but first, dinner
Also bought the wheels there. Double.
Eh, wrong rail. Bought V rail.
And these wheels.https://umakovshop.com/push-up-pulley-complete-d-80-mm-5fb055a229f6f4001b840632
If I read aqvisdeck's brochure correctly, they use 160x61 mm aluminum profiles (doesn't specify which type) spaced at 450 mm. In your case, it would be ten or eleven beams. The maximum span without additional reinforcement beams is, however, 6400 mm between the wheels, so you would definitely need extra reinforcement beams. Unfortunately, I can't find any information about their extra beams other than a picture. So it is possible with aluminum, but it requires a lot more than just edge reinforcements.
Their basic construction weighs 19 kg/m^2, which with decking becomes about 40 kg/m^2 (their specification). In your case, it would be approximately 1500 kg (8.4*4.2*40=1411.2). About what your solution weighs too. They size for 100 kg of snow per square meter, which with deadweight in your case becomes around 5 tons (8.4+4.2*140=4939.2).
Based on these figures, I would size the deflection after 1500 kg (given that the insulation doesn't absorb moisture and complicate things) and size the strength after 5 tons (avoid running the roof with the load).
Unfortunately, aqvisdeck doesn't specify deflection, but from their distance between the bottom edge and the wheel track, one can conclude that the deflection is less than 30 mm (the deck is 195 mm high, including wheels but without decking). The deck should never be rolled while loaded.
With these starting values, one could calculate different solutions, such as:
- Two strong (cambered) steel beams
- Three or more (possibly cambered) beams (with enough, perhaps aluminum, otherwise steel)
- Self-supporting sheet metal
What do others think, are the values I've borrowed from aqvisdeck a reasonable starting point?
Their basic construction weighs 19 kg/m^2, which with decking becomes about 40 kg/m^2 (their specification). In your case, it would be approximately 1500 kg (8.4*4.2*40=1411.2). About what your solution weighs too. They size for 100 kg of snow per square meter, which with deadweight in your case becomes around 5 tons (8.4+4.2*140=4939.2).
Based on these figures, I would size the deflection after 1500 kg (given that the insulation doesn't absorb moisture and complicate things) and size the strength after 5 tons (avoid running the roof with the load).
Unfortunately, aqvisdeck doesn't specify deflection, but from their distance between the bottom edge and the wheel track, one can conclude that the deflection is less than 30 mm (the deck is 195 mm high, including wheels but without decking). The deck should never be rolled while loaded.
With these starting values, one could calculate different solutions, such as:
- Two strong (cambered) steel beams
- Three or more (possibly cambered) beams (with enough, perhaps aluminum, otherwise steel)
- Self-supporting sheet metal
What do others think, are the values I've borrowed from aqvisdeck a reasonable starting point?