Civil Engineering Association

1.1 This European Standard establishes general principles for the execution of bored piles.

1.2 This European Standard applies to bored piles with:
— uniform cross-section (straight shaft);
— telescopically changing shaft dimensions;
— excavated base enlargements; or
— excavated shaft enlargements.

1.4 This European Standard applies to piles with the following rake (see Figure 4): — n ≥ 4 (Θ ≥ 76°); — n ≥ 3 (Θ ≥ 72°) for permanently cased piles.
1.5 This European Standard applies to bored piles with the following dimensions of the shaft or base enlargements (see Figure 3):
a) base enlargements:
1) in non-cohesive ground: DB / D ≤ 2;
2) in cohesive ground: DB / D ≤ 3;

b) shaft enlargements in any ground: DE / D ≤ 2;
c) slope of the enlargement in non-cohesive ground m ≥ 3; 1) in non-cohesive ground: m ≥ 3; 2) in cohesive ground: m ≥ 1,5;
d) base enlargements area of barrettes: A ≤ 15 m²;

1.6 The provisions of this European Standard apply to:
— single bored piles;
— bored pile groups;
— walls formed by piles.

1.7 The bored piles which are the subject of this European Standard can be excavated by continuous or discontinuous methods using support methods for stabilizing the excavation walls where required.

1.8 This European Standard applies only to construction methods that allow the designed cross-sections to be produced.

1.9 The provisions apply to bored piles constructed of:
— unreinforced (plain) concrete;
— reinforced concrete;
— concrete reinforced by means of special reinforcement such as steel tubes, steel sections or steel fibres;
— precast concrete (including prestressed concrete) elements or steel tubes where the annular gap between the element or tube and the ground is filled by concrete, cement or cement-bentonite grout.

1.10 Micropiles, mixed-in-place columns, columns constructed by jet grouting, ground improvement for piling, mixed-in-place pile bases and diaphragm walls are not covered by this European Standard.