CONCRETE SEALERS
Concrete sealers for use
in protecting concrete from chloride intrusion shall meet the requirements of
applicable Iowa Department of Transportation Specifications. Sealers generating a shiny surface are listed in the
Appendix A. They are intended for use only on bridge substructure areas such as
pier tops and abutments. Sealers that do not affect surface texture are shown
in the Appendix B. The sealers listed in the Appendix B can be applied
to the bridge decks and the bridge substructure areas. It is not intended that either type of concrete
sealer be applied over the entire bridge deck surface. Materials that are
penetrating and crystalline forming to block moisture and can be applied to the
entire surface of traffic areas are shown in the Appendix C.
Acceptance of concrete sealers for use on the Department of Transportation projects will be on the basis of manufacturer and brand name approval. Approved manufacturers and brands of concrete sealers are listed in the Materials Approved Products Listing Enterprise (MAPLE) as the Appendixes A and B for different applications.
To obtain approval of a concrete sealer under the Appendixes A and B, manufacturer shall submit the following items to the Office of Construction and Materials in Ames, Iowa:
1. Product identification including brand name and product number;
2. Complete manufacturer recommendations of usage including coverage rate;
3. Current Safety Data Sheet (SDS);
4. If available, independent test data showing the effectiveness of the sealer in preventing chloride intrusion; and
5. A sample consisting of at least 1 quart of sealer.
The
laboratory evaluation will consist of testing in accordance with AASHTO T 259:
"Resistance of Concrete to Chloride Ion Penetration," except a C-3
mix shall be used. and sandblasting prior to
applying sealer shall be omitted. For
a sealer used only on non-traffic surface area, sandblasting prior to applying
sealer shall be omitted. For a sealer that can be used on traffic and
non-traffic areas, the sandblasting shall be done before applying sealer.
The chloride content of the treated concrete at the 1/16 in. to 1/2 in. depth shall not exceed 10 percent of the control concrete at the same depth.
Approval of a concrete sealer may be withdrawn because of deficient monitor test results; product changes made after original approval, or unsatisfactory field performance.
Manufacturer shall file a certification statement at the beginning of each calendar year stating that the material supplied during that year is identical with the formulation previously tested and approved by the Office of Construction and Materials.
The Office of Construction and Materials may sample and test concrete sealers to verify compliance with specifications.