Splitting of wood column

[GalileoG]

I have attached a picture to this post of a wood column that has a significant split on it. The building is at least 15+ years old and this column is exposed to environmental effects (snow, rain, etc.) I understand that splits like this can happen when wood shrinks and is nothing to worry about. However, this split seems to be significant and appears to have originated where the bolt-through at the base use to be (it's missing now...I wonder how.) The size of the split has me concerned. How would I go about repairing the split? I suppose some sort of an adhesive? Your input is appreciated.

 

[MiketheEngineer]

This exact subject was discussed extensively just a few weeks ago. Suggest you search it and we don't start another long post...

 

[hokie66]

Mike, I think this is different enough from the other thread to stand on its own. The split probably started due to corrosion of the through bolt. This split has gone all the way through, so that a triangular chunk is now separate from the column. The simplest repair may be to prop and replace the post. Closer examination is required of the base condition, which may be compromised by corrosion.

 

[GalileoG]

Thank you for the responses.

Hokie66, I've attached another picture of a close-up of the column base. There is no corrosion visible. I suspect the split was initiated at the bolt-through location but it doesn't look like it was because of any corrosion. It also seems like the bolt-through was removed at some point in a vain attempt to prevent further splitting.

So column replacement is the only remedy?

 

[msquared48]

I would be concerned with reduced end bearing of the column, plus rot of the end allowing vertical settlement over time, possibly causing distress in the bolt and the subsequent splitting of the column that we see.

Mike McCann
MMC Engineering

http://mmcengineering.tripod.com

 

[SAIL3]

Comments on this post and previous posts on the subject of splits in wood columns and to some extent beams seem to take a casual approach to the problem and nothing to worry about.
This not meant to be a criticism as they are from experienced engineers ,but leave me with the following questions.
To me a split in wood may not be static and can progress over time.
It is difficult to determine the extent of the split by visual inspection with any degree of certainty.
A wood col that has a significant split in my understanding could be sigificantly weakened as the original stability of the col was based on the whole x-section where now with a split could be based on 2 or 3 smaller x-sections.

 

[DLBennett]

I agree with Galileo, the crack may have initiated at the bolt as the bolt may have received all of the load. This explanation would collaborate with the bolts later removal. Bolt bearing may have occurred due to poor construction or end rot (as Mike suggested). I think replacement of the column very soon is by far the best option, it is relatively cheap. Trying to repair the column would probably be as expensive.
Don Bennett
Lone Star Engineering, PC

http://www.lonestarengineeringpc.com

 

[shobroco]

Obviously looking at a photograph is not the same as looking at the column, but it appears that the split could have occured as a result of the column twisting as it dried and being restrained by the bolt. Column (square) sections typically contain the heart of the log simply because of sawmill practice in boxing out the heart to produce the greatest high-quality lumber from the perimeter of the cant. Sections containing the heart are very prone to twisting and splitting. GalileoG says there is no visible corrosion, but doesn't comment on rot. Regardless, replacement appears pretty cheap compared to unsatisfactory and unsightly repairs. Replace it and specify a section not containing the heart.

 

[MiketheEngineer]

This is obviously much more drastic than the previous post. I didn't realize that and apologize for simply suggesting you search the old posts.

Two things -

1. It can "possibly" be fixed if the vertical loads are not too high - say 75-80% of normal capacity.

2. Best bet would to replace it if at all possible. As noted that may be the more economical solution.