28 July 2005
In certain situations, where tugboats or camels are not available, sheet pile
bulkheads located along the offshore face of pier and wharf structures may be
less desirable than open type construction because of the greater danger for
contact between the sheet piling and the bulbous bow or sonar dome of a ship
during berthing and unberthing maneuvers.
Track Mounted Crane.
Where a track-mounted crane is required for the pier or wharf, the solid type may
not be suitable. The susceptibility of the solid filled type to settlement and
movement will make it very difficult to maintain the close tolerance required for
rail gage, elevation, and alignment. The surcharge loading on the sheet pile will
also be considerable. For such cases, use an independent pile supported track.
Several aspects of construction that are unique to each structural type should be
For open type wharves and landside ends of open piers, the following schemes
should be considered for retaining upland fill:
a. Platform on Piles and a Curtain Wall at the Inshore Face. See Figure
2-9. The underwater slope should be as steep as possible, as limited by
both constructional and geotechnical parameters, thus making the pile-
supported platform narrow and more economical. In seismically active
areas, where hydraulic fill susceptible to liquefaction is used for upland fill,
a rock dike may be used instead of the granular fill dike to resist the lateral
forces caused by liquefaction of the fill. The use of a filter fabric also
should be considered at the hydraulic fill interface.
b. Platform on Pile and a Sheet Pile Bulkhead at the Inshore Face. See
Figure 2-9. The sheet pile bulkhead permits a narrower platform. The
cost tradeoff between platform width and bulkhead height should be
investigated as the bulkhead may be found to cost as much or more than
the pile supported platform width saved.
Retaining structures may be constructed by the following means:
a. Sheet Pile Bulkhead. See Figure 2-10. The bulkhead consists of a
flexible wall formed of steel or concrete sheet piling with interlocking
tongue and groove joints and a cap of steel or concrete construction. The
bulkhead is restrained from outward movement by placing an anchorage
system above the low water level. Many types of anchorage systems can