1020.8 Laboratory Testing Guidelines for Sec 1020
This article establishes procedures for Laboratory testing and reporting samples of metallic-coated steel culvert metal. Refer to Sec 1020 for MoDOT's specs.
Laboratory tests desired on the sample will be designated by the inspector in the remarks area in AASHTOWARE Project (AWP). Normally, the only Laboratory tests required are mass of coating on each sample and chemical analysis approximately once a year. If two samples from different districts are submitted for chemical analysis within a period of one month from the same manufacturer and base metal, only one of the samples need be tested. Other tests shall be performed when requested.
1020.8.1.1 Chemical Tests
The procedure for determining mass of coating shall be according to AASHTO T65 for zinc coated and T213 for aluminum coated. Mass of coating shall be reported as ounces per square foot (Kg per square meter), double exposed surface. Chemical composition of the base metal shall be determined according to the following methods set forth in ASTM E30-68; exclusive of any later revisions thereto:
- (a) Carbon - Direct Combustion method.
- (b) Manganese - MoDOT Test Method T57.
- (c) Phosphorus - Alkalimetric method.
- (d) Sulfur - Evolution method.
- (e) Silicon - Sulfuric Acid method
Original test data and calculations shall be recorded in Laboratory workbooks. Test results shall then be recorded through AASHTOWARE Project (AWP).
1020.8.1.2 Physical Tests
Gage and thickness shall be determined with a micrometer graduated in increments of 0.0001 in .(.00254 mm) A minimum of five thickness measurements are to be made on the tangents of corrugations and at least 3/8 in.(9.5 mm) from the edge of metal. Both the minimum and average thickness results shall be reported, to 0.001 in .(.0254 mm) All other processes requested by the inspector shall be performed as prescribed in Sec 1020. Test results shall be recorded through AWP.
1020.8.2 Sample Record
The sample record shall be completed in AASHTOWARE Project (AWP), as described in AWP MA Sample Record, General, and shall indicate acceptance, qualified acceptance, or rejection. Appropriate remarks, as described in EPG 106.20 Reporting, are to be included in the remarks to clarify conditions of acceptance or rejection. Laboratory and field test results shall be reported on the appropriate templates under the Tests tab.