Expert On Pre-stressed Concrete Visiting City

Press, Volume CII, Issue 30275, 30 October 1963, Page 23

Expert On Pre-stressed Concrete Visiting City

Jfte-CBOtang at concrete, combined with pre-stressing, was flourishing in New Zealand, said Mr A. J. Harris, a London organ dhing engineer, in an interview with “The Pre«B" yesterday. New Zealanders had done some interesting structures showing imaginative use of the two techoiquea. There was not the volume of production here that there was in overseas countries, but it certainly was increasing and New Zealanders were always very reedy to learn, he said. “We know that well, for we always have a number of Ner.v Zealand engineers chi our staff in London. They stay with us two or three years and then return home —to our regret,” Mr Harris said.

‘Tm a yachtsman and I’ve been greatly interested to do some sailing in this country. I've actually seen one or two concrete teats which show great promise,” he said.

Mr Harris, a world authority on pre-stressed concrete, came to New Zealand to address a symposium on pre-casting in Wellington. He will address engineering students at the University of Canterbury today, and will later go to Dunedin to address engineers and architects. “While I am in New Zealand I am also having a look at engineering works of interest,” he added. Mr Harris was on the Normandy end of the Mulberry harbour construction work

tor the landings on the beaches during the Second World War. He was in Normandy the day after D-Day. He served with the Royal Engineers during the war. Mr Harris said there had been a very big increase in the amount of pre-casting for structures of all types and sizes from single-storey buildings to big bridges and harbour works. The advent of pre-stre®ing had resulted in a huge increase to the use of pre-CBSting. A simple example of precasting wias the concrete telegraph pole which was cast at a factory under good conditions and transported to the site. The other extreme would be a multi-storey block of flats composed of small panels transported to the site and put together there. In the other technique, that of pre-stressing concrete, very high grade steel was used and it was stretched so that it compressed the concrete.

Pre-stressing enabled a targe structure to be built with small panels which were tensioned together with steel wires.