1. Precast Concrete Pipe and Box Culvert Equipment Calibration
To Trust What We Measure
And To Maintain Consistency

2. Calibration of Testing / Inspection Equipment for RCP
Calibration of Equipment
Check all quality control testing equipment and calibrate them, as required in ASTM C 497. A reputable licensed testing laboratory shall calibrate all jacks and gauges for the three-edge-bearing test equipment at least once every twelve-month period.
Source: FDOT Materials Manual, Section 6.2, Vol. II

3. Calibration of Testing / Inspection Equipment for Precast RCB
Calibration of Equipment
Check or calibrate all quality control testing equipment such as the batching scales, compressive strength testing machines, portable weighing scales, air meters, density buckets, and temperature recording devices for compliance with the applicable test methods.
Source: FDOT Materials Manual, Section 6.3, Volume II

4. Equipment Calibration
Three Edge Bearing (3EB) Rack
Compressive Strength Tester
Hydrostatic Pressure Gauge
Water Meter
Batch Plant Scales
Laboratory Scales
Admixture Dispenser
Joint Gauging Equipment
Temperature Gauge (Thermometer)
Micrometers

5. 3EB Test Equipment

6. What is the history of the 0.01 inch crack in RCP?!
What is the history of the 0.01 inch crack in RCP?
In 1920s/1930s, everyone had their own idea of a “crack” when performing the 3EB test. There was no standard of d-load crack measurement.
A 0.01-inch thick feeler gauge was decided to be the standard by which the d-load crack width would be defined.
It is an arbitrary standard of measurement born out of the need for consistency and practical application.

7. 3EB Calibration
4.4 Calibration—The loading device shall be one which shall provide an accuracy of  2 % at the specified test loads. A calibration curve shall be used. The machines used for performing the three-edge-bearing tests shall be verified in accordance with Practices E 4.
Source: ASTM C 497 Standard Test Methods for Concrete Pipe, Manhole Sections, or Tile

8. Weighing Scales for Absorption
7.4.5 Scale Sensitivity—Weigh specimens weighing less than 1 kg to an accuracy of 0.10 % of the specimen mass. Weigh specimens weighing more than 1 kg to an accuracy of 1g.
Source: ASTM C 497 Standard Test Methods for
Concrete Pipe, Manhole Sections, or Tile

9. Hydrostatic Joint Test Pressure Gauge Calibration
16.3 Apparatus:
Hydrostatic pressure tests on joints shall be made on
an assembly of two sections of pipe, properly connected in accordance with the joint design. The hydrostatic pressure shall be measured with a gage or manometer accurate to  5 % of the test pressure.
The testing machine shall be of any type that has
sufficient capacity to apply the required test load, that is in
addition to the weight of the pipe filled with water, or a suitable dead load shall be applied.
Source: ASTM C 497 Standard Test Methods for
Concrete Pipe, Manhole Sections, or Tile

10. Compressive Strength Calibration
ASTM C 39
Standard Test Method for Compressive Strength of Cylindrical Concrete Specimens
Verify calibration:
At least annually, not to exceed 13 months
Upon installation or relocation
After making repairs or adjustments…
Whenever accuracy of loads is suspect
Paragraph 5 (Apparatus)
5.3 Load Indication

11. Thermometer Calibration
ASTM C 1064
Standard Test Method for Temperature of Freshly Mixed Hydraulic-Cement Concrete
Calibrate using two thermometers
Calibrate at two temperatures
At least 30 degrees difference between tests

12. Calibration Summary Consistency in Measurements
Applies to all Test Instruments / Devices
Check FDOT and ASTM Specs
ASTM Test Method Specification
Allowable Limits
Frequency of Calibration
Method of Calibration