19 June 2001
SR-7: PATCHING STEEL SHEET PILE WALL
Problem: Steel sheet pile wall has small to medium holes. General condition of
sheet piling is otherwise sound with minimum signs of corrosion.
Description of Repairs: Clean around area to be patched. For larger holes
using steel plate patches, clean sheet piling from 460-mm (18-inch) below holes
to above mean low water.
Epoxy Patch: Weld wire mesh or bolt fabric mesh over holes and cover with
epoxy-polyamide putty smeared on by hand (see Figure 8-7). Good for a limited
number of small holes.
Steel Plate Patch: Determine size of patch plate needed. Cut plate to size and
bend plate to fit over sheet pile interlocks. Weld plate in place at top, above low
water. Cut holes for Tee bolts in sheet piling behind holes in plate; place and
tighten Tee bolts (see Figure 8-7). Alternative is to weld plate all around, which is
more appropriate for larger holes or several small holes.
Patch and Pressure Grouting: Where several small holes make pure patching
cost expensive, a combination of patching and grouting may be a better solution.
In this approach, cover the larger holes with epoxy or steel plate patches, then
pressure grout the area behind the wall (see Figure 8-7).
Application: This approach will not prevent further corrosion and its success
depends on the surrounding areas of sheet piling being relatively sound and free
from rust. Continued deterioration of a weak structure, particularly near tiebacks,
could lead to rapid failure and poor use of repair funds. Economics should govern
final selection of the repair method.
Future Inspection Requirement: Increased inspection will be required at the
patch areas to ensure that welds and bolted connections continue to hold.