20081015095623.pdfECOVSD
09 October 2008, Revised o c T 13 2008
Ann Bullis, Plan Reviewer and BUILDING DEPT.
Building Code Official
Development Services Department
121 5tr, Avenue North, Second Floor
Edmonds, Washington 98020
Dear Ann Bullis:
This is a review on the Revised Road and Shoring Plans for the:
Project Name: Port Edwards retaining structure near NW comer, South Amenity Building
CKCTm Plan Review No. 1149-408 (City Plan Review Number 2008-0426)
Grading and Shoring Issues
1. The Lock-Block Retaining Wall system doesn't seem to have any ICC Evaluation Report
associated with it. There are approved reports at: http://www.icc-es.org/reportslindex.cfm
but most of them are for the UBC, and all rely on geo-grid material to hold them back.
2. The Lock -Block Retaining Wall website does shows its basic design criteria at this link:
http://www. lockbiock_.c_om/design.html. Its design should show that "dead weight," from the
blocks that are at a slope of 1 horizontal to 10 vertical provides the resistance. The shear
between layers of the blocks is resisted by the raised circular "dowels" which fit into
matching holes in the block above it as shown in its website's proprietary literature.
3. The revisions mentioned in the three Terra Associates' Reports and shown, in part, on the
plans should provide relief for pressure on the slope where a failure occurred assuming the
wall didn't reach a height where "tie back" systems including the use of geo-grid materials
would be required.
4. Therefore, the maximum specified height of the wall, 7'-0", and the height of the new 2:1
backfill slope, 1'-6", need to be specified so that it is stable and doesn't affect the main
lower slope (it is shown in -the soils report, but the plans are what get stamped.)
5. The minimum distance away from the bottom block to the sloping soil face, 3'-0", also
needs to be shown on the Engineer signed Shoring plans to ensure the bearing soil
pressure from the Lock -Block system's wall •weightAoesn'f cause another sloughing
failure.
6. Additionally, there should be special inspection provided for the Lock -Block Retaining Wall,
or any other wall manufacturer's installation, if an alternative is used. Presumably, this will
be the Soils Engineer
CLOSING
Thank you for the opportunity to be once more of service. I will be submitting any invoice for this
review for the 4.5 hours I took to review the plans.
Sincerely,
Jerry J. Barbera, P.E.
Construction Codes Consultant