asked the Minister of Transport what are the conditions of traffic and climate in this country that are so different from those of the United States of America as to prevent the acceptance by his Department of the findings of the American Association of State Highway Officials road test that concrete roads were superior to asphalt roads for fast heavy traffic.
§ Mr. Hay
The concentration in time of heavy axle loading in the test traffic was from five to ten times that on a normal heavily trafficked road in Great Britain. It was not mixed traffic such as is carried on roads in Great Britain. The depth of frost penetration at the test site was almost double that normally experienced in Great Britain.
We are advised that highway engineers in the U.S.A. recognise the limitations of 20W the test and that further experiments under normal road conditions are being staged.