AS/NZS 2891.14.1.2:2013 PDF Download

The AS/NZS 2891.14.1.2:2013 standard specifies the method for determining the field density of compacted asphalt layers using a nuclear surface moisture-density gauge in the backscatter mode. This method is suitable for asphalt layers ranging from 50 to 100 mm thick, with a nominal maximum size not exceeding 40 mm. However, the standard does not provide instructions on how to operate the gauge, as it refers the operator to the manufacturer's handbook for that information.

It is important to note that when using nuclear gauges for density measurement, the exact quantity of material being assessed is not known. This standard recommends referring to the manufacturer's handbook and current literature to estimate the likely volume. The backscatter mode in a nuclear gauge provides an indirect measure of field density, therefore requiring calibration in accordance with AS/NZS 2891.14.4. Regular checks on the operation and calibration of the gauge are also necessary.

To carry out field density testing using the backscatter mode, a density offset must be determined for each combination of asphalt mix and layer thickness that will be tested. This is outlined in Appendix B of the standard.