A precambered beam! I like it.
Sami won't approve it? but build a brick pillar in the centre of the span..
Sami won't approve it? but build a brick pillar in the centre of the span..
Steel beam size
- Thread starter sami69
- Start date
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A pre-cambered beam = pre-cambered masonry.
Surely then when it settles it will cause inevitable cracking?
Surely then when it settles it will cause inevitable cracking?
Well...you'll get the same amount of dead load deflection either way, so I would think that the risk of cracking is the same, precambered or not?
The opening will house 2 fixed panels of glass at each end of 2.5m each which do not open.The middle section of 5m are sliding doors, they are bottom hung.
The glass doors and tracks are been manufactured and are on site - cannot change pillar widths/extra pillars etc now as glass was ***** expensive and made to measure. It was the installers who noticed the deflection to date and were unable to fit sliding doors as they would not work with the amount of deflection at the beam center. Structural engineer has made a major balls up of the steel calc and structure design. We never met him until problem surfaced as he was appointed by the architect. Many steels have been installed in the project - only this one has been cocked up.
We cannot put a huge steel eg 305X305x240UC as the piers would not be able to take it most likely. This would have kept the total max deflection below 7mm with live & dead load.
Having thought about it, I have come up with a simple solution that might work. If we install 305x305x137UC, max deflection should reduced to 22mm considering live+dead load (I found a beam calculator on the net). The steel has come off now. If we made the opening 25mm higher so the beam sits 25mm higher, Any deflection upto a max of 25mm would not impact the doors. The sliding doors people have trim that could be put on the outside to hide the gap. Hopefully any deflection would not come anywhere near the max calculated.
Anyone think I'm bonkers or could this work? I'm assuming I have calculated all loads correctly & calculator is correct.Had a sleepless night when Tony told me that only live load deflection would be less than 7mm yesterday.
What I don't understand is how two SE could have specified a new steel only considering the live load deflection despite knowing the total deflection (live&dead load) has to be 7mm or less otherwise there would be impact on the doors.
I was thinking Tony must be wrong but the more I looked into it last night and using the calculator he seems to be spot on.
Complete nightmare!
The glass doors and tracks are been manufactured and are on site - cannot change pillar widths/extra pillars etc now as glass was ***** expensive and made to measure. It was the installers who noticed the deflection to date and were unable to fit sliding doors as they would not work with the amount of deflection at the beam center. Structural engineer has made a major balls up of the steel calc and structure design. We never met him until problem surfaced as he was appointed by the architect. Many steels have been installed in the project - only this one has been cocked up.
We cannot put a huge steel eg 305X305x240UC as the piers would not be able to take it most likely. This would have kept the total max deflection below 7mm with live & dead load.
Having thought about it, I have come up with a simple solution that might work. If we install 305x305x137UC, max deflection should reduced to 22mm considering live+dead load (I found a beam calculator on the net). The steel has come off now. If we made the opening 25mm higher so the beam sits 25mm higher, Any deflection upto a max of 25mm would not impact the doors. The sliding doors people have trim that could be put on the outside to hide the gap. Hopefully any deflection would not come anywhere near the max calculated.
Anyone think I'm bonkers or could this work? I'm assuming I have calculated all loads correctly & calculator is correct.Had a sleepless night when Tony told me that only live load deflection would be less than 7mm yesterday.
What I don't understand is how two SE could have specified a new steel only considering the live load deflection despite knowing the total deflection (live&dead load) has to be 7mm or less otherwise there would be impact on the doors.
I was thinking Tony must be wrong but the more I looked into it last night and using the calculator he seems to be spot on.
Complete nightmare!
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I think the whole "yawning" aperture is bonkers, impractical and resembling a car showroom window. That gaping mess at the back of your house looks silly.
It's amazing how people can be sucked in by seductive design ideas only to find out that they are totally unworkable in domestic situations.
You have my condolences.
Sorry Noseall but I think you are very very wrong and giving somebody 'condolences' on their home??
This sort of opening might look ridiculous on some properties but given the size of Sami's house personally I think it could look absolutely fantastic.
You are a very knowledgable and helpful fellow, but this is a question of aesthetics which will always be subjective. Just because you don't like the look of it doesn't make it a failure, we can't all like the same things otherwise the world would be a very boring place.
Sami, I love what you are trying to do. I really hope you find a way to resolve the issues.
But please please please post pics once it is all sorted, I'd love to see the finished item!
I agree with noseall. The extension has a ceiling too low for that size opening .... that type of design.
It's been poorly thought out IMO, in terms of technical, practical and design aspects.
Design is not just about finding a steel beam to fit at the last minute
It's been poorly thought out IMO, in terms of technical, practical and design aspects.
Design is not just about finding a steel beam to fit at the last minute
Why not? When designing piers, it's not the weight of the beam that is the issue, but the weight that is carried by the beam. You end up with around an extra 5kN each end if you use a 240kg beam rather than a 137, which is probably not significant when the whole load is taken into account.
This is what I was talking about above. Raise the ends of the beam so that the doors don't bind under maximum load, or precamber the beam so that it's flat under full dead load.
noseall,
I understand you would have prefered my 10m 'yawning' aperture to be half filled with brick. What would I have done with that brick wall - hung a few pictures on it? I want my garden to be the picture.... and I wanted to add a wow factor to the house. In essence it is more of a modern conservatory.
There is nothing impractical about it, it's not 10m of folding doors - only 5m of sliding glass. The rest of the glass is fixed. You seem to have no problem with it if the fixed glass was replaced by brick? Do you think the image below - something similar to what I am doing is is "bonkers, impractical and resembling a car showroom window"? I beg to differ..
There should have been no problem with building it.. it's not exceptionally difficult. The structural engineer made a mistake and I now I need to find a way of rectifying it.
As they say, beauty is in the eye of the beholder. You may not like the look of it, but I love what I will have once the issue is rectified and certainly don't need your condolences...
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