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#42
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Disaster waiting to happen? Using PVC for deck supports???
scrumble said something like:
wrote: On Sun, 18 May 2008 18:28:11 -0400, Matt Whiting wrote: wrote: On Sun, 18 May 2008 18:02:54 GMT, "Thomas G. Marshall" . com wrote: There was a person I was speaking to recently who was proud of what he considered to be a very bright move on his part. He had noticed that the lolly-columns in his basement had been filled with cement prior to being used. He assumed that the strength of the support was in the cement, and therefore concluded it was a good idea to try filling PVC tubes and using those as posts (note-not as sonno-tubes, but as fully structural support posts). I pointed out that I thought that the strength of a lolly was in the steel, and that the cement was there merely to ensure that it was never dented, causing it to fold like an aluminum can. I was concerned that the first major frost heave under his deck that is able to stress the ledger enough to pull outward a small amount would cause his pvc+cement "posts" to break. Was I right? The concrete in steel lolly columns is to help keep them from collapsing in a fire. It also does provide much improved buckling resistance. Yes, buckling that would be caused by the heat of a FIRE. But surely if that was the only reason for the concrete it would far easier and cheaper just to coat the steel with an intumescent paint? I agree, but further, this is an odd "argument". I look also at the things that might happen in a basement. Heavy things could be moved around and dent the column. It would take a hell of a whack to do that, but it seems to me that filling the thing with concrete is an incredibly cheap way of ensuring that a column doesn't collapse in such an [albeit rare] event. Further, having seen what my 3 1/2 and 1 1/2 year old consider game for smacking with a rock or hammer, I'm thinking that substantially removing the notion of disaster with concrete innards is a great idea. And I can imagine a young person able to swing a sledge hammer thinking it a "funny idea" to send a shock wave through the house, thinking perhaps that the lolies were solid steel or somesuch. |
#43
Posted to alt.building.construction,alt.home.repair
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Disaster waiting to happen? Using PVC for deck supports???
Matt Whiting said something like:
....[snip]... I didn't see a column length in the OP, but when "basement" is the description rather than "crawl space" it is likely that the length is at least 6' and possibly 8' or even more. This is far from being a 1' column. Concrete filled PVC could work if sized properly, but using the same size as the existing steel column is a fool's errand. Again, the OP didn't mention the size of either the steel or the PVC, but I'll bet there were likely nearly the same size. If that is the case, then the PVC is almost certainly inadequate, unless the steel column was grossly oversized for the required load. In my original post I believe I was clear in using the steel column reference only in what the person I met had used as his reasoning for filling them with concrete. I pointed out that HE was under the impression that the strength of the steel column was primarily the concrete within it, and he believed that the steel was a mere form for it. Hence he figured that using nearly anything as a form, e.g. PVC, would be enough for the deck supports. I am not sure of the diameter. I am not sure of the length. I am not sure that they were also the footings (though I hope not, since I doubt he understands the notion of "big feet" and I doubt he was using hugely wide posts). But I have seen concrete cracks in all kinds of things, and I can't help but imagine a crack going clear through one of those things causing a disaster. YMMV {shrug} |
#44
Posted to alt.building.construction,alt.home.repair
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Disaster waiting to happen? Using PVC for deck supports???
CWatters said something like:
"Thomas G. Marshall" . com wrote in message news:ib_Xj.134$ay2.84@trndny01... There was a person I was speaking to recently who was proud of what he considered to be a very bright move on his part. He had noticed that the lolly-columns in his basement had been filled with cement prior to being used. He assumed that the strength of the support was in the cement, and therefore concluded it was a good idea to try filling PVC tubes and using those as posts (note-not as sonno-tubes, but as fully structural support posts). For what? I mentioned the deck in the subject and in the paragraph you snipped. But I was not as clear as I could be: he was using them as the posts. -- Onedoctortoanother:"Ifthisismyrectalthermometer,wh erethehell'smypen???" |
#45
Posted to alt.building.construction,alt.home.repair
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Disaster waiting to happen? Using PVC for deck supports???
wrote:
On Wed, 21 May 2008 21:18:25 GMT, "Thomas G. Marshall" . com wrote: scrumble said something like: wrote: On Sun, 18 May 2008 18:28:11 -0400, Matt Whiting wrote: wrote: On Sun, 18 May 2008 18:02:54 GMT, "Thomas G. Marshall" . com wrote: There was a person I was speaking to recently who was proud of what he considered to be a very bright move on his part. He had noticed that the lolly-columns in his basement had been filled with cement prior to being used. He assumed that the strength of the support was in the cement, and therefore concluded it was a good idea to try filling PVC tubes and using those as posts (note-not as sonno-tubes, but as fully structural support posts). I pointed out that I thought that the strength of a lolly was in the steel, and that the cement was there merely to ensure that it was never dented, causing it to fold like an aluminum can. I was concerned that the first major frost heave under his deck that is able to stress the ledger enough to pull outward a small amount would cause his pvc+cement "posts" to break. Was I right? The concrete in steel lolly columns is to help keep them from collapsing in a fire. It also does provide much improved buckling resistance. Yes, buckling that would be caused by the heat of a FIRE. But surely if that was the only reason for the concrete it would far easier and cheaper just to coat the steel with an intumescent paint? I agree, but further, this is an odd "argument". I look also at the things that might happen in a basement. Heavy things could be moved around and dent the column. It would take a hell of a whack to do that, but it seems to me that filling the thing with concrete is an incredibly cheap way of ensuring that a column doesn't collapse in such an [albeit rare] event. Further, having seen what my 3 1/2 and 1 1/2 year old consider game for smacking with a rock or hammer, I'm thinking that substantially removing the notion of disaster with concrete innards is a great idea. And I can imagine a young person able to swing a sledge hammer thinking it a "funny idea" to send a shock wave through the house, thinking perhaps that the lolies were solid steel or somesuch. What can I say? Filling lolly columns with concrete FOR FIRE SAFETY is part of THE CODE in many places. What is a lolly column? Is that anything like a lally column? What place has this in the fire code? Here is a reference that clearly states that the main purpose for filling the columns is strength. And it discusses that the concrete can actually be detrimental in a fire in certain conditions although it certainly is beneficial in other conditions. Bottom line is that filling the columns with concrete is not done primarily for reasons of fire resistance. It is for strength first and fire resistance is a nice fringe benefit. http://books.google.com/books?id=FVF...en#PPA 329,M1 Matt |
#46
Posted to alt.building.construction,alt.home.repair
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Disaster waiting to happen? Using PVC for deck supports???
CJT wrote:
wrote: On May 20, 3:53 pm, "JoeSpareBedroom" wrote: wrote in message ... On May 20, 3:40 pm, CJT wrote: CWatters wrote: wrote in message ... On Sun, 18 May 2008 18:28:48 -0400, Matt Whiting wrote: Thomas G. Marshall wrote: said something like: ...[snip]... The concrete in steel lolly columns is to help keep them from collapsing in a fire. ....so the preventing a dent thing is secondary, or not a concern...? No, preventing buckling is a significant advantage provided by filling a steel column. Matt Uh, yes. And the buckling it prevents would be the result of fire. Filling the columns with cement is to protect the columns from buckling in a FIRE. PVC burns doesn't it? So does steel. -- The e-mail address in our reply-to line is reversed in an attempt to minimize spam. Our true address is of the form .- Hide quoted text - - Show quoted text - Steel burns? I guess I learned something new today. ============ Anything will burn at the right temp.- Hide quoted text - - Show quoted text - So there's no difference between burning and melting? Sure there is. Steel will do either (or both) depending on the conditions. Exactly, the perfect example is to consider what is actually happening when you squeeze the lever on a cutting torch. |
#47
Posted to alt.building.construction,alt.home.repair
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Disaster waiting to happen? Using PVC for deck supports???
On May 22, 5:53*pm, George wrote:
CJT wrote: wrote: On May 20, 3:53 pm, "JoeSpareBedroom" wrote: wrote in message .... On May 20, 3:40 pm, CJT wrote: CWatters wrote: wrote in message om... On Sun, 18 May 2008 18:28:48 -0400, Matt Whiting wrote: Thomas G. Marshall wrote: said something like: ...[snip]... The concrete in steel lolly columns is to help keep them from collapsing in a fire. ....so the preventing a dent thing is secondary, or not a concern...? No, preventing buckling is a significant advantage provided by filling a steel column. Matt Uh, yes. And the buckling it prevents would be the result of fire. Filling the columns with cement is to protect the columns from buckling in a FIRE. PVC burns doesn't it? So does steel. -- The e-mail address in our reply-to line is reversed in an attempt to minimize spam. Our true address is of the form .- Hide quoted text - - Show quoted text - Steel burns? I guess I learned something new today. ============ Anything will burn at the right temp.- Hide quoted text - - Show quoted text - So there's no difference between burning and melting? Sure there is. *Steel will do either (or both) depending on the conditions. Exactly, the perfect example is to consider what is actually happening when you squeeze the lever on a cutting torch.- Hide quoted text - - Show quoted text - That, imho, is a perfect example of melting, not "burning" http://www.newton.dep.anl.gov/askasc...6/gen06008.htm |
#48
Posted to alt.building.construction,alt.home.repair
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Disaster waiting to happen? Using PVC for deck supports???
wrote:
On May 22, 5:53 pm, George wrote: CJT wrote: wrote: On May 20, 3:53 pm, "JoeSpareBedroom" wrote: wrote in message ... On May 20, 3:40 pm, CJT wrote: CWatters wrote: wrote in message news:39j134h08gs30kb4kq0djaas296spst46m@4ax .com... On Sun, 18 May 2008 18:28:48 -0400, Matt Whiting wrote: Thomas G. Marshall wrote: said something like: ...[snip]... The concrete in steel lolly columns is to help keep them from collapsing in a fire. ....so the preventing a dent thing is secondary, or not a concern...? No, preventing buckling is a significant advantage provided by filling a steel column. Matt Uh, yes. And the buckling it prevents would be the result of fire. Filling the columns with cement is to protect the columns from buckling in a FIRE. PVC burns doesn't it? So does steel. -- The e-mail address in our reply-to line is reversed in an attempt to minimize spam. Our true address is of the form .- Hide quoted text - - Show quoted text - Steel burns? I guess I learned something new today. ============ Anything will burn at the right temp.- Hide quoted text - - Show quoted text - So there's no difference between burning and melting? Sure there is. Steel will do either (or both) depending on the conditions. Exactly, the perfect example is to consider what is actually happening when you squeeze the lever on a cutting torch.- Hide quoted text - - Show quoted text - That, imho, is a perfect example of melting, not "burning" http://www.newton.dep.anl.gov/askasc...6/gen06008.htm some of it does indeed burn. if you don't believe me, hold a match under a wad of 0000 steel wool. Outside, or in a deep sink... nate -- replace "roosters" with "cox" to reply. http://members.cox.net/njnagel |
#49
Posted to alt.building.construction,alt.home.repair
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Disaster waiting to happen? Using PVC for deck supports???
On Thu, 22 May 2008 15:21:41 -0700 (PDT),
wrote: On May 22, 5:53*pm, George wrote: Exactly, the perfect example is to consider what is actually happening when you squeeze the lever on a cutting torch.- Hide quoted text - - Show quoted text - That, imho, is a perfect example of melting, not "burning" http://www.newton.dep.anl.gov/askasc...6/gen06008.htm Reference aside, do you know what cutting torch is how it works? A cutting torch *burns* the steel using a stream of oxygen that is triggered by the lever, though the steel must be hot enough that it will burn first. However, not all the steel is burned, some does fly off as molten metal. Melting a material changes its state. The state can be restored by lowering its temperature. Burning a material changes the material's composition usually combining it with oxygen to form a new substance (iron oxide, for exmaple) Once a material is burned lowering its temperature won't restore it. |
#50
Posted to alt.building.construction,alt.home.repair
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Disaster waiting to happen? Using PVC for deck supports???
On May 23, 10:56*am, RicodJour wrote:
On May 23, 9:37 am, PeterD wrote: On Thu, 22 May 2008 15:21:41 -0700 (PDT), wrote: On May 22, 5:53 pm, George wrote: Exactly, the perfect example is to consider what is actually happening when you squeeze the lever on a cutting torch.- Hide quoted text - - Show quoted text - That, imho, is a perfect example of melting, not "burning" http://www.newton.dep.anl.gov/askasc...6/gen06008.htm Reference aside, do you know what *cutting torch is how it works? A cutting torch *burns* the steel using a stream of oxygen that is triggered by the lever, though the steel must be hot enough that it will burn first. However, not all the steel is burned, some does fly off as molten metal. Melting a material changes its state. The state can be restored by lowering its temperature. Burning a material changes the material's composition usually combining it with oxygen to form a new substance (iron oxide, for exmaple) Once a material is burned lowering its temperature won't restore it. And how many angels did you get to dance on the head of that pin? You're engaged in sophistry. *We are discussing steel columns and house fires. *For all intents and purposes there is no burning of a steel column. *But feel free to continue the debate - let me know when you feel you're winning. R- Hide quoted text - - Show quoted text - Really, I sit corrected--steel does burn! |
#51
Posted to alt.building.construction,alt.home.repair
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Disaster waiting to happen? Using PVC for deck supports???
On Fri, 23 May 2008 07:56:33 -0700 (PDT), RicodJour
wrote: We are discussing steel columns and house fires. For all intents and purposes there is no burning of a steel column. But feel free to continue the debate - let me know when you feel you're winning. R I always win, or so my wife tells me. For some reason I have to believe her--I think it is because she told me so. That said... Steel columns in a house fire are not an issue. The house will be long gone before they fail. What we *were* discussing was whether cement in a column (of any composition) adds strength, and if so, how much, and as well why add cement. Cement is added to a Lally column to prevent collapse or pinching failures. Who cares what happens when the steel softens to the point of failure? The game's over at that point regardless, the house will be long gone, and the failure of other members of the structure will make any column's ability to withstand fire a non-issue. But, what the heck, let's argue onwards. |
#52
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Disaster waiting to happen? Using PVC for deck supports???
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#53
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-probably_junk- Disaster waiting to happen? Using PVC fordeck supports???
wrote:
- Show quoted text - Steel burns? I guess I learned something new today. ============ Anything will burn at the right temp.- Hide quoted text - - Show quoted text - So there's no difference between burning and melting? Sure there is. Steel will do either (or both) depending on the conditions. Exactly, the perfect example is to consider what is actually happening when you squeeze the lever on a cutting torch.- Hide quoted text - - Show quoted text - That, imho, is a perfect example of melting, not "burning" http://www.newton.dep.anl.gov/askasc...6/gen06008.htm Actually no, consider what the extra oxygen supplied when you squeeze the lever is supporting. |
#54
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Disaster waiting to happen? Using PVC for deck supports???
wrote:
On Sat, 24 May 2008 07:57:32 -0400, Matt Whiting wrote: wrote: On Fri, 23 May 2008 20:26:04 -0400, PeterD wrote: On Fri, 23 May 2008 07:56:33 -0700 (PDT), RicodJour wrote: We are discussing steel columns and house fires. For all intents and purposes there is no burning of a steel column. But feel free to continue the debate - let me know when you feel you're winning. R I always win, or so my wife tells me. For some reason I have to believe her--I think it is because she told me so. That said... Steel columns in a house fire are not an issue. The house will be long gone before they fail. What we *were* discussing was whether cement in a column (of any composition) adds strength, and if so, how much, and as well why add cement. Cement is added to a Lally column to prevent collapse or pinching failures. Who cares what happens when the steel softens to the point of failure? The game's over at that point regardless, the house will be long gone, and the failure of other members of the structure will make any column's ability to withstand fire a non-issue. But, what the heck, let's argue onwards. The firemen trying to save people in the house may care a lot about that concrete in those columns. That's why the building fire safety codes insist on them being there. I've seen two claims of fire codes requiring concrete fill, yet I've seen no reference posted to a fire code that does require that in residential construction. Reference?? Check with your local building department. As I suspected ... you are just making up stuff. |
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