Bolted connection between pile cap and pile.

[Raquib]

Any thoughts on bolted connection between pile cap and screw pile. We are thinking of it to reduce field welding cost. But our structure is sensitive to lateral movement and moment. Please see attached picture and comments. Thank you.

 

[paddingtongreen]

It looks like investing two dollars to save one by the time you jig up and drill those holes on opposing sides.

Michael.
"Science adjusts its views based on what's observed. Faith is the denial of observation so that belief can be preserved." ~ Tim Minchin

 

[Raquib]

Sorry I missed one information. Pile cap plate and 356 mm Diameter pipe is connected by all around 8mm fillet shop weld.

 

[Raquib]

Few bolt connections will be shop drilled. My supervisor things we will be able to save money this way. I am concern about saving money along with pile movement and stability issue between pile cap and pipe bolted.

 

[Brad805]

I doubt it will work out to be a savings. Screw piles are notorious for wandering during installation and the bolted connection will end up field welded 85% of the time.

 

[Raquib]

It seems to me that adding up all the field drill & field bolting time and probability of field weld due to pile movement, will make the project more costly than straight field welding for everything from the beginning.

 

[TXStructural]

If you have the welder on site to do some connections, may as well let him/her weld it all. The expense with field welding is not making the welds, it is mobilizing the trade. And since you cannot add capacity of bolts and welds, you'll probably end up welding it all anyway.

I agree with Brad, and you may well end up with the need for holes where you cannot drill and bolt without conflict.
Also, if you are planning one-for-one pile-for-column as drawn, chances are good you will have large eccentricity.