1. Acceptance of epoxy-coated steel reinforcement will be as follows:
a. Black reinforcing steel originates from an approved manufacturer of steel reinforcement. Approved manufacturers of reinforcing steel are listed in IM 451 Appendix D. All steel reinforcement shall be melted and manufactured in the USA.
b. Epoxy coating has been applied by an approved epoxy coater as listed in Appendix A of this IM.
c. Steel reinforcement is supplied through approved distributors/suppliers/fabricators listed in Appendix E of this IM.
d. Unless otherwise specified, deformed bars shall meet the requirements of ASTM A 615 / A 615M, ASTM A 706 / A 706M or ASTM A 996 / A 996M.
e. Approved epoxy powders and patching compounds are listed in Appendix B of this IM.
f. An identification list, invoice, or bill of materials for each shipment to a project that contains:
i. the project and design number
ii. name and location of the epoxy coating plant, and supplier/fabricator if different from coating plant.
iii. the size, length, grade, heat numbers and number and weight of pieces in the shipment,
iv. A copy of Mill certificates from the black steel manufacturer, a copy of epoxy powder certificates, and epoxy coating test certificates.
v. It shall also contain a certification stating that the attached Mill Certifications and epoxy-coating certifications are applicable to the material.
vi. Each epoxy coated bondel shall have a tag showing the heat number, mill, and the coater’s name.
g. All products of steel and iron shall be of domestic origin and shall be melted and manufactured in the USA.
2. Approval will be subject to the testing of acceptance and verification samples secured at destination as outlined herein.
3. All reinforcement (deformed and plain) required to be epoxy-coated shall have a protective coating of epoxy applied by the electrostatic spray method in accordance with the requirements of ASTM A775/A775M, except as outlined in this IM.
4. Job site handling of epoxy-coated reinforcing steel bars shall be in accordance with the requirements of ASTM D3963/D3963M and IM 451.03B.
5. Approval to coat, furnish or fabricate epoxy-coated steel on a certification basis may be withdrawn for deficient test results on verification samples, inadequate documentation or identification of materials, or deficient monitoring inspections.
6. Approved coaters shall submit a complete copy of the annual CRSI inspection report to the Materials Office of the Iowa Department of Transportation (DOT) for continual approval.
7. Approved coaters shall be on the approved list prior to the letting.
Refer to IM 451.03B Appendix A
SUPPLIER/FABRICATION SHOP APPROVAL
Refer to IM 451.03B Appendix E.
Refer to IM 451.03B Appendix B.
1. Each shipment to a project shall have an identification list, invoice, or bill of materials showing:
a. the project and design number,
b. Name and location of epoxy coating plant and supplier/fabricator if different from coating plant.
c. the size, length, grade, heat number and number and weight of pieces in the shipment,
d. A copy of Mill certificates from the black steel manufacturer, a copy of epoxy powder certificates, and epoxy coating test certificates.
e. It shall also contain a certification stating that the attached Mill Certifications and epoxy-coating certifications are applicable to the material.
2. The Mill Certifications for black steel shall state the chemical, physical, and mechanical tests reported and the ASTM designation, type, grade, heat number, and source for all heats represented in the shipment.
3. The epoxy-coating test certifications originating from the epoxy coating plant shall provide the coating lot number and powder lot numbers for the heat numbers included in the shipment and the quality control test results for coating thickness, coating continuity, profile measurements and coating flexibility for all coating lots represented in the shipment.
4. The epoxy powder certifications shall be for the powder lot numbers for all coating lots represented in the shipment.
For each shipment to a project from a supplier or fabricator: one copy of the documents prescribed above shall accompany each shipment and be retained in the Project Engineer file.
For shipments from all approved Epoxy Coating Plants: Two copies shall be forwarded at the time of shipment (whether directly to a project site or to a supplier/fabricator); one to the Central Materials Office in Ames, Iowa, and one to the District Materials Office responsible for project administration or warehouse stock monitoring.
Monitoring inspection of the coating plants may be required for deficient test results on verification samples and any other samples that have failed, have inadequate documentation, materials misidentification, or significant changes (non-compliance) in CRSI inspection reports.
VERIFICATION SAMPLING & TESTING
The location of the sample within a bar shall be at least 3 ft. (1 m) from the ends of the bar.
NOTE: Coated bars that show any amount of rust (trace, moderate or heavy) shall not be sampled and shall not be accepted; and shall be considered grounds for rejection.
For each project, Personnel from the District Materials Office shall secure a random field verification sample 6 ft. (2 m) of any size bar in the project.
For coating plants that have been approved on a project-by-project basis, a random acceptance sample, 6 ft. (2m) of any size bar for each shipment, shall be secured and tested for coating thickness and flexibility (bend test) prior to incorporation into the project.
Two additional samples of the same size shall be secured if the first sample indicates non-compliance. Non-compliance may be considered a cause for rejection. If a bar size in a shipment is rejected, a similar sampling procedure shall be applied to the remaining bar sizes in the shipment.
The verification sample and acceptance sample will be the same sample. The District Materials Office will randomly sample any bar size of the epoxy coated steel for the deck. If the sample fails, two additional random samples of the same size shall be secured. Noncompliance on any one of the additional samples shall be cause for rejection of that particular size in the shipment.
If a bar size in a shipment is rejected, a similar sampling procedure shall be applied to the remaining bar sizes in the shipment.
The contractor shall not place concrete on the deck until there are passing test results of the epoxy-coated steel.
Samples of epoxy-coated steel reinforcement for bridge decks shall be limited to one sample per project.
Each shipment of epoxy-coated pavement tie bars shall be accepted by a letter of compliance identified with the county, project number, and contractor. This letter shall itemize the following:
1. Quantity of material shipped
2. A certification statement that assures the material was fabricated in accordance with approved shop drawings, and indicates the approval date of the drawings
3. A statement for epoxy coating shall include the name of the coating company, compliance with ASTM A775, and indicate that the coating reports for the material are retained in the files of the assembly supplier (subject to review by the Iowa Department of Transportation).
4. Copies of Mill Test Reports of heat numbers of steel used in fabrication of the tie bars
5. The supplier shall retain the records of Coating Reports and Mill Test Reports for three years.
6. Samples of epoxy coated steel reinforcement for all applications shall be one sample per project.
This compliance document shall be distributed in accordance with IM 451, paragraph titled, "Certification Acceptance Procedures."
STEEL FROM WAREHOUSE SUPPLY
The District Materials Engineer shall sample epoxy-coated reinforcing steel, which is shipped to a supplier, fabricator or contractor for use on several projects, at the above-indicated rates.
QUALITY REQUIREMENTS FOR EPOXY COATED BARS
The coating plant shall maintain an updated Quality Control Manual. The coating plant shall also have a trained designated Quality Control Inspector, as well as trained personnel to serve as back-up inspectors for every production shift. Inspection and testing shall be performed in a timely manner during each production shift.
The Plant is responsible to maintain a record of Quality Control monitoring and testing, and document Quality Control meetings and training with personnel.
Reinforcing steel surfaces to be coated shall receive a thorough blast cleaning to near-white metal in accordance with SSPC SP10. Mill scale, rust and foreign matter shall be completely removed. The blasting media shall produce a suitable anchor pattern profile. A minimum profile depth of 2.0 mils to a maximum depth of 4.0 mils (50 µm to 100 µm) shall be considered suitable as an anchor pattern. Coating shall be applied to a cleaned surface soon thereafter. In no case shall the coating be delayed more than 0.5 hr. after cleaning.
The abrasive blasting media shall be inspected for contamination every production shift and a sieve analysis shall be performed at a minimum of twice per week.
Additional blast media containing sufficient grit shall be required if a suitable anchor pattern and/or profile depth has not been achieved. A maximum of 10% steel shot may be added to the blast media.
· A single recorded epoxy coating thickness measurement shall be the average of three individual gage readings obtained between four consecutive deformations. A minimum of five recorded measurements shall be taken approximately evenly spaced along each side of the test bar (a minimum of 10 measurements per bar).
· Note: All individual gage readings shall be reported along with the averages.
· Note: The upper thickness limit shall not apply to repaired areas of damaged coating.
· Test for coating thickness shall be made on a minimum of two bars every two production hours, or whenever bar size changes.
Coating continuity shall be monitored by:
· An In-Line Holiday detector
· A Hand-held Holiday detector (wet sponge type)
Hand-held Holiday detection checks shall be performed at a minimum rate of once per shift. The accuracy of the In-Line System shall be compared to the accuracy of the Hand-held detector at all times. There should be fairly close correlation between the Hand-held and In-Line Holiday counts. Only 1 Holiday per 1.0 linear foot (3 Holidays per meter) shall be allowed over the length of the coated bar.
A bend test shall be performed to evaluate the flexibility of the coating. Coated bars shall be tested at a uniform rate, a minimum of one bar of each size every four production hours around a mandrel of a specified size within a maximum specified time period. (See Table 1, ASTM A775/AA775M.) No cracking or disbonding of the coating shall be visible on the outside radius of the bent bar. Evidence of cracking or disbonding of the coating shall be considered a cause for rejection. The test bars shall be between 68˚F and 86˚F (20˚C and 30˚C) when tested.
Epoxy Powder shall be stored in a suitable
temperature and humidity controlled environment
The powder shall be kept dry at all time. The Epoxy powder shall be used within the manufacturer’s recommended shelf life. Epoxy powder that has exceeded the manufacturer’s “Use-By” date shall not be used.
All systems for handling epoxy coated steel bars shall be padded. All bundling bands shall be suitable banding to prevent damage to coating. All bundles of epoxy coated steel bars shall be carefully lifted to prevent bar-to-bar abrasion, sagging of bars, and/or damage to coating.
Long-term storage (greater than two months) of bars shall be minimized at the fabricator and at the job site. Coated steel reinforcing bars shall be stored off the ground on protective cribbing, and/or on padded support with padded timbers placed between bundles when stacking is necessary. Sufficient supports shall be spaced evenly to prevent sags in the bundles during storage.
Epoxy coated steel reinforcing bars stored outdoors longer than two months either at the fabricator or at the project site shall be protected from sunlight, salt spray and weather exposure. The coated bars shall be covered with a non-transparent material, or other suitable opaque protective material. Provisions shall be made for adequate ventilation to minimize condensation. The date on which the coated bars are placed outdoors shall be recorded on the identification tag of the bundled steel. Weathered (discolored) bars shall be rejected.
If coated bars have been stored outside at the coater for a period of six months or longer from the date of coating, the coater shall inspect, sample, and retest the bars prior to shipment to a warehouse or project site. If coated bars have been stored indoors at the coater for a period of one year or longer from the date of coating, the coater shall inspect, sample and retest the bars prior to shipment to a warehouse or project site. Bars shall be retested for coating thickness and flexibility (bend test). A copy of the test results shall be attached to original coating report.
Epoxy coated bars that have been stored at the project site for a period of six months or longer from the date of coating may be inspected, sampled, and retested prior to use at the discretion of the District Materials Engineer.
Points of contacts for epoxy coated bars shall have padded contact areas.
Coated epoxy bars or bundles shall not be dropped or dragged.
NOTE: Coated and uncoated steel reinforcing bars shall be stored separately.
Supports shall be spaced sufficiently to prevent sags in the bundles.
Epoxy coated tie wires and bar supports shall be used with epoxy coated reinforcentment to prevent damage to the coating.
Coated epoxy bars or bundles shall be stored above the ground on wooden or padded supports with timber placed between bundles when stacking is necessary.
H. COATING REPAIR MATERIAL
· The patching or repair materials shall be compatible with the coating as required per ASTM D3963/D3963M and Appendix B of this IM.
· Sheared ends and / or saw cut ends of coated reinforcing bars shall have adequate coating, have no signs of surface rust or damage, and shall be coated and / or repaired with approved patch / repair material listed in Appendix B.
· Repaired / Patched areas shall be allowed to cure (dry to touch) before concrete placement over the coated bars.
· Surface preparation, repair, and patching application procedures shall be in accordance with the powder manufacturer’s recommendations.
Coated bars that do not meet the requirements of this IM, ASTM A775/A775M, ASTM D3963/D3963M, and the requirements of IM 451.03B and Specification 4151.03 shall be rejected. Rejected bars shall be marked with contrasting color paint or other suitable identification and stored separately.