Road Testing Modernised

The Ministry of Works employees pictured on this page, with their machinery, are conducting what is known as the "California Bearing Ratio Test", which is a new mechanical method of valuing the sub-grade strength of the ground carrying a main highway.

By placing weight on a small portion of the road for a set period of time, the amount of depression or buckling is recorded on micrometers down to thousandths of an inch.

From these readings can be calculated the quantity of metalling and sealing required to bring the road up to state highway standards.

On this occasion D. H. Bennets, with his assistants Kiri Patuwai and Colin Ria, was testing the sub-grade strength of upper Gladstone Road.