Geotechnical Data and Pile Design - Offshore Structures: Design, Construction and Maintenance - page 283

Blows per 0.25 meter

0 50 100 150 200 250 300

0

MRBS3000,lower bound SRD

MRBS3000,upper bound SRD

MRBS3900,lower bound SRD
MRBS3900,upper bound SRD
DelmagD80,lower bound SRD
DelmagD80,upper bound SRD

10

20

30

40

50

60

70

FIGURE 4.17 Blowcount versus depth for three types of hammers and 30-inch pile with 1 4 -inch wall
thickness.

given to incorporation of a pile shoe to prevent undue distress to the pile during
driving through the cemented layers.
The shoe should be externally flush, should have an appropriate outer bevel
profile at the tip, and should have an increased wall thickness over a suitable
length. As with an overall increase in pile wall thickness requiring some addi-
tional drivability assessment, the incorporation of a pile shoe will also need to
be with regard to its effect on pile-driving behavior.