CONCRETE V. MACADAM

Hokitika Guardian, 16 July 1919, Page 4

CONCRETE V. MACADAM

EXPERTS REPORT ON PALMERSTON EXPERIMENT.

PALMERSTON NORTH, July 10. !

Tlie Kairanga County Council contemplates going in for improved methods in road construction, but so far it has been unable to chose between the respective merits of concrete and tar macadam. Two experimental pieces of road were laid down iii the county about a year ago one in concrete and the other in macadam. At a meeting of the Council Messrs Toogood and Mail- submitted a comprehensive report on the concrete experiment on 'Rangitikci Line, which was carried out bv Councillor Craw a year ago. The report stated that they were favourably impressed with the surface appearance of the road, except for pitting caused by drift w T ood in the river shingle having worked to the surface during the process of laying the concrete, and the covering film of mortar having been worn away. The signs of wear were no greater than usually found in this class of road, but they were not prepared to recommend further work on the same lines without an extensive test.

Roth engineers were strongly of the opinion that before deciding upon the eonjstruction of .concrete -roads the council should decide whether it intended to countenance or on the other hand discourage by tlie means within its power heavy traction-engine traffic. This was important, because in considering the construction of concrete roads the question of width of wheels, weight of load, and traction engine traffic must be taken into account. The class of road under review would bo suitable for twelve ton loads on suitable tyres, but not for the heaviest form of traffic. Mr Craw’s road would require a carpet of bituminous compound in a few years, but this was used with all concrete roads.

The vexed question as to what the experiment actually cost was settled by the engineers, who estimated that it had cost Mr Craw £213 to lay down five chains of road in concrete. Ordinarily, they considered that it would cost more than this sum to construct this class of road. At the next meeting of the council, Messrs Hair- and Toogood will submit a report on the tarred-macadam experiment.