A comparison of design practice of bored piles/drilled shafts between Europe and North America

Figures & data

1 Examples of diverse geologic conditions for drilled shaft design

2 Design approaches outlined in Eurocode 7

3 Diversity of European practice with bored pile design

4 Rock core samples for drilled shaft design

Table 1 Boring requirements for drilled shafts in AASHTO code

Redundancy condition	Shaft diameter (ft [m])	Guideline
Single column, single shaft foundations	All	One boring per shaft
Multiple shaft foundations in soil	≥6 ft [1.83 m]	One boring per shaft
Multiple shaft foundations in soil	<6 ft [1.83 m]	One boring per four shafts
Multiple shaft foundations in rock	All	One boring per shaft

Table 2 Ground test results (n = number of profiles)

for n =	1	2	3	4	5	7	10
	1.55	1.47	1.42	1.38	1.36	1.33	1.30
	1.55	1.39	1.33	1.29	1.26	1.20	1.15

5 Components of concrete for drilled shafts/bored piles (Figure credit: Beckhaus 2016)

Beckhaus, K. 2016. Concrete for Deep Foundations. ISSMGE - ETC 3 International Symposium on Design of Piles in Europe. Leuven, Belgium, 28 & 29 April 2016.

 Google Scholar