All testing of bituminous materials for compliance with specification in the UK is carried out in accordance with one of the methods in British Standard BS 598 which currently require the use of chlorinated solvents. An alternative method using a radioactive source in a nuclear gauge is assessed in this report. The results demonstrated the ability of the nuclear gauge to operate over a wide range of binder contents and types of bituminous material. The results also showed that the nuclear-based measurements were very close to the line of equality and that the scatter was less than that obtained with the two analytical methods currently specified in BS 598. The work showed that the repeatability of the nuclear method was superior to that of the analytical methods. (A)
Abstract