Concrete Research Being Conducted In New Zealand

Bay of Plenty Beacon, Volume 14, Issue 82, 6 January 1950, Page 5

Concrete Research Being Conducted In New Zealand

Materials used in the concrete and cement for dam construction in New Zealand are being subjected to intense scientific research in order to avoid failures similar to those that have occurred overseas.

Very serious failures have occurred in the United States of America when certain, aggregates of volcanic origin have been used in the construction of concrete dams, and research workers of the Dominion Laboratory, Department of Scientific and Industrial Research, are trying to find out by chemical and physical tests whether aggregates of similar origin found in New Zealand are likely to have the same unsatisfactory properties. In the U.S.A. it is now becoming common practice to add finely ground siliceous admixtures to the concrete used for major dam projects, especially where the aggregate is under suspicion. The purpose is to counteract expansive troubles caused by harmful aggregates. Since the admixture is used as a replacement of part of the cement, considerable savings of cement are possible. Research has been put in hand at the Dominion Laboratory with the object of finding out if any of our local materials are suitable for such a use.

Volcanic deposits from several localities in New Zealand are at present under examination by chemical and conductivity tests in order to see if they have the properties of increasing in concrete its resistance to corrosion. Some of New Zealand’s deposits show considerable promise, but for confirmation of the Laboratory findings extensive practical strength tests have yet to be made.