Minimum Pile Spacing Before Group Effect on Lateral Capacity 1

[BigEasyGeoSleuth]

What are you geotechs using for the minimum pile spacing before group effect needs to be considered for lateral load capacity for drilled shaft groups? I have seen 6D.

For Auger Cast Pile groups? (may be less due to the auger providing lateral support??)

 

[SlideRuleEra]

http://www.asce-sf.org/downloads/clay_tests.pdf

and

http://www.asce-sf.org/downloads/clay_analysis.pdf

http://www.SlideRuleEra.net

 

[Panars]

I think the latest AASHTO code uses 5D as the limit.

 

[eric1037]

Poulos and Davis have a good discussion on this in "Pile Foundation Analysis and Design".