19 June 2001
INSTALLING A CONCRETE CAP/FACE ON A TIMBER SHEET
: Large-scale deterioration
of the timber sheet pile structure has
occurred precluding the use of patches for repairs.
Description of Repairs: Excavate the soil from behind the wall to a level
required for the new concrete cap or attachment of form ties for a concrete face.
Remove all marine growth and deteriorated wood, and clean the surfaces.
To repair a concrete cap -- Build forms, place reinforcing, and pour concrete at
MLW. After curing, remove forms and backfill behind the wall (see Figure 6-11).
To repair a concrete face -- Place and fasten blocking and low wale against
existing sheetpiling. Drive the timber sheet pile wall about 30 cm (1 foot) in front
of existing sheetpiling using the wale as a guide. Attach outside wales to timber
sheeting and place concrete by pumping or tremie. Leave timber sheet piling in
place or remove as desired (see Figure 6-11).
Application: Used to restore structural strength at the top of the wall (cap) or
prevent further loss of soil through holes in the sheetpiling (face). Does not
restore bending moment capacity in wall. Provides protection against further
Future Inspection Requirement: Do an annual inspection of sheetpiling areas
immediately under the pile cap, in order to ensure that fungi, insect, or marine
borer damage is not weakening the support for the concrete cap.