Civil Engineering Reference
In-Depth Information
Cast-in-place concrete
Cast-in-place
piles (shells driven
concrete piles
Pile type
Timber
Steel
without mandrel)
(shells withdrawn)
Maximum length
35 m
Practically unlimited
45 m
36 m
Optimum length
9-20 m
12-50 m
9-25 m
8-12 m
Applicable material
ASTM-D25 for piles; P1-54 for
ASTM-A36 for structural
ACI
ACI*
specifications
quality of creosote; C1-60 for
sections
creosote treatment (standards of
ASTM-A1 for rail sections
American Wood Preservers Assoc.)
Recommended
Measured at midpoint of length:
f
s
65 to 140 MPa
0.33
f
c
; 0.4
f
c
if shell gauge
14;
0.25
f
c
-0.33
f
c
maximum stresses
4-6 MPa for cedar, western
f
s
0.35
f
y
-0.5
f
y
shell stress
0.35
f
y
if
hemlock, Norway pine, spruce,
thickness of shell
3 mm
and depending on code
5-8 MPa for southern pine,
Douglas fir, oak, cypress, hickory
Maximum load for
270 kN
Maximum allowable
900 kN
1300 kN
usual conditions
stress
cross section
Optimum load
130-225 kN
350-1050 kN
450-700 kN
350-900 kN
range
Disadvantages
Difficult to splice
Vulnerable to corrosion
Hard to splice after concreting
Concrete should be placed
Vulnerable to damage in hard driving
HP section may be damaged
Considerable displacement
in dry hole
Vulnerable to decay unless treated,
or deflected by major
More than average
when piles are intermittently
obstructions
dependence on quality
submerged
of workmanship
