obtained from a simple triangle of forces as shown. Where lateral forces are transient in
character, for example, for wind loadings, they may be permitted to be carried wholly or
partly by the pile cap where this is bearing on the ground (see Section 7.8). If raking piles
are installed in fill or compressible soil which is settling under its own weight or under a
surcharge pressure, considerable bending stresses can be induced in the piles, requiring a
high moment of resistance to withstand the combined axial and bending stresses as
discussed in Section 6.4.
Piles to resist uplift and lateral loading 307
Tie rod
Wholly
compression
Wholly tension Sheet-piling
Alternating
tension and
compression
Chimney
Wind
Bridge pier
Braking and
acceleration
loads
(a)
(b)
(c)
Figure 6.3Raking piles to resist overturning forces. (a) Piled anchorage to tie rods restraining
sheet-piled retaining wall (b) Raking piles to withstand wind forces on chimney (c) Raking
piles to withstand traction forces from vehicles on bridge.
Fender
Bollard
Figure 6.4Raking and vertical piles in breasting dolphin.