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How to avoid tall concrete piers

Nothing. Gravity is performing the task of keeping them in place. I think a hinge point is created from the loads above (is that axial load?). The crazy thing is they would have been fine with CMU piers.
 
Sifu said:
Nothing. Gravity is performing the task of keeping them in place. I think a hinge point is created from the loads above (is that axial load?). The crazy thing is they would have been fine with CMU piers.
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Hi Sifu,

Neither position is supported. Those piers are fine as long as none are involved in any braced wall lines.

Bill
 
GBrackins said:
so the 6x6's are being on the small 1" piece between the open cells of the cmu?
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What informs you that they're not solids on the top course? The piers in the fore ground are indistinguishable as to the courses. Check out the piers in the background.

Bill
 
A short pier at the bottom with the 6x6 to the floor would probably been the best.

The fundamental problem is the failure to involve an architect or engineer when the building exceeds the proscriptive limitations in the code. The problem is agrevated when jurisdictions allow such "creative approaches" because of lack of enforcement or because there is no engineer in the building department
 
I believe this has been clarified in the 2009 IRC at least for BWP........

R602.10.7 Braced wall panel support. Braced wall panel support shall be provided as follows:

1. Cantilevered floor joists, supporting braced wall lines, shall comply with Section R502.3.3. Solid blocking shall be provided at the nearest bearing wall location. In Seismic Design Categories A, B and C, where the cantilever is not more than 24 inches (610 mm), a full height rim joist instead of solid blocking shall be provided.

2. Elevated post or pier foundations supporting braced wall panels shall be designed in accordance with accepted engineering practice.

Mark K said:
A short pier at the bottom with the 6x6 to the floor would probably been the best.The fundamental problem is the failure to involve an architect or engineer when the building exceeds the proscriptive limitations in the code. The problem is agrevated when jurisdictions allow such "creative approaches" because of lack of enforcement or because there is no engineer in the building department
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The piers are solid. I thought the question asked was if they were "attached", which they are not however they do "rest" on a solid pier. I can find no code that doesn't permit this, I just think it would have been better as a continuous cmu pier. The code allows them to be 10 times the least dimension which would have been greater than the height they needed to be. I did not tag this I just thought it ironic that the builder thought it was the only way to pass inspection. As I said, I don't think it is a good practice. In fact as I write this I do seem to remember the code does require that the bottoms of wood columns need to be restrained, though I don't think this application is what that requirement was meant for. A question occurs to me though, would it be permissable to use a 6x6 directly from the footing to the floor? Answer: yes. How about if the 6x6 was cut in two and stacked one on top of the other?
 
This is about as strange a thread as I've seen here. The 6"x6" is toenailed to the girder and "resting" on the CMU and you are asking if that's OK?
 
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ICE said:
This is about as strange a thread as I've seen here. The 6"x6" is toenailed to the girder and "resting" on the CMU and you are asking if that's OK?
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Give it a few years, lateral loads......lateral loads......lateral loads......

quakefailedhouse.jpg
 
I looked at the picture and thought it looked like a pretty dumb way to solve a problem... then I remembered the picture I posted yesterday of rubblestone piers 42" above a porch floor with wood posts to the porch roof.

I believe Mark's pic is a soft story problem caused by a a weak braced wall on the streefront?
 
ICE said:
This is about as strange a thread as I've seen here. The 6"x6" is toenailed to the girder and "resting" on the CMU and you are asking if that's OK?
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Not asking if its OK. Pretty clear I don't like it but I don't find a code that says its not OK. Code allows wood columns, allows CMU columns, the only code I can find that might apply is the one requireing restraint at the bottom of wood columns.
 
Builder Bob said:
The contractor answer is Bull.......... The piers can be built, however, they may require a double or triple bond pier to be constructed with rebar and an adequate footing. I hate seeing crap like that as the end user will be screwed.
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Does not the code clearly permits solid column heights 10 times their least dimension. '06 IRC 606.6
 
I believe Mark's pic is a soft story problem caused by a a weak braced wall on the streefront?

i believe marks picture is the aftermath of a san francisco or l.a. earthquake!
 
Sifu said:
Not asking if its OK. Pretty clear I don't like it but I don't find a code that says its not OK. Code allows wood columns, allows CMU columns, the only code I can find that might apply is the one requireing restraint at the bottom of wood columns.
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All columns require restraint at the bottom

When the columns are composed of different materials you are now out of the prescriptive path of the IRC that is why you can't find a provision in the code telling you how to put them together and when that happens a DP should be involved. The IRC code does not tell you what is NOT okay it tells you what is allowed prescriptively. Just because the IRC is silent on a paticular way to construct something does not mean it is permited.

R301.1 Buildings and structures constructed as prescribed by this code are deemed to comply with the requirements of this section.

R301.1.3 Engineered design.

When a building of otherwise conventional construction contains structural elements exceeding the limits of Section R301 or otherwise not conforming to this code, these elements shall be designed in accordance with accepted engineering practice

R407.3 Structural requirements.

The columns shall be restrained to prevent lateral displacement at the bottom end. Wood columns shall not be less in nominal size than 4 inches by 4 inches (102 mm by 102 mm) and steel columns shall not be less than 3-inch-diameter (76 mm) standard pipe or approved equivalent.

Exception: In Seismic Design Categories A, B and C columns no more than 48 inches (1219 mm) in height on a pier or footing are exempt from the bottom end lateral displacement requirement within underfloor areas enclosed by a continuous foundation.
 
Update on the column picture. I went to a seminar last week taught by a DP and this type of thing came up. I showed him the photo and he said while it didn't make any sense it was not a clear code violation and that lateral forces would not be a big concern within the crawlspace. (that was my worry) I still have concerns over the axial(?) loads and the potential hinge joint in the column but I don't put P.E. after my name.
 
Lateral force is not a concern because the floor that the piers and posts support is restrained on all four sides. Toss an earthquake into the equation and what do you get. The post isn't attached to the pier....the post is toenailed to the girder.
 
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