EUROCODE 2 WORKED EXAMPLES - Federbeton

EC2 – worked examples 6-29
Tied reinforcement in the pile: 8 φ 26 (A s = 4248 mm 2 )
The compressive stress F c in the concrete and the steel tension F s on the pedestal pile are
evaluated from the ULS verification for normal stresses of the section itself:
Fs = fyd As = 391.3·4248 = 1662242 N = 1662 kN
N Sd = 0.8 b x f cd – F s ⇒ 2000000 = 0.8·700·x·14.17 − 1662242 ⇒ x = 462 mm
The compressive stress in the concrete is:
C = 0.8 b x fcd = 0.8·700·462·14.17 = 3666062 N = 3666 kN
(applied at 0,4⋅x ≅ 185 mm from the upper surface)
piles stress
pile stresses are evaluated considering the column actions transfer in two steps:
in the first step, the transfer of the forces Fc e Fs happens in the plane π1 (Fig. 6.17) till to the
orthogonal planes π2 and π3, then in the second step the transfer is inside the planes π2 and π3 till to the piles;
the truss-tie beam in Fig. 6.18 is relative to the transfer in the plane π1: compression: A’ = (MSd/3.00 + NSd/2) = (4000/3.00 + 2000/2) = 2333 kN
tension: B’ = (MSd/3.00 - NSd/2) = (4000/3.00 - 2000/2) = 333 kN
for each compressed pile: A=A’/2 = 1167 kN
for each tied pile: B=B’/2 = 167 kN
In the evaluation of stresses on piles, the plinth own weight is considered negligible.
Table of Content
Fig. 6.18. S&T model in the plane π1.