ICPI 25th Anniversary Commemorative Publication ICPI 25th Anniv Commemorative Album 0219 web - Page 18

An NCMA paver committee meeting in August 1981 in Hershey, PA, addressed developing an ASTM specification for concrete pavers. Committee member Lee Martin who represented Zenith Equipment suggested replicating Germany’s national product specification which included a minimum average compressive strength of 8,700 psi (60 MPa). This requirement likely enhanced freeze-thaw durability and probably obviated the need for freeze-thaw testing in Germany. That proposal didn’t go over well with some block manufacturers who proposed 7,200 psi. The pictures that follow illustrate some of the early and salient flagship projects. A subsequent meeting of the paver committee in winter 1982 was a boisterous one where concrete masonry manufacturers were wondering why 8,000 psi or higher compressive strengths were needed. Some masonry manufacturers and especially paver manufacturers in non-freezing climates were pressing for 7,200 psi (50 MPa). In the meantime, NPCA introduced a standard for balloting at ASTM with 8,000 psi (55 MPa) as the minimum average compressive strength. That ballot was approved by ASTM and published in 1982. Significantly higher than most cast- in-place concrete pavements, the minimum average strength of 8000 psi remains to this day. The number of paver manufacturers grew substantially in the 1980s who introduced interlocking concrete pavement into various markets in the U.S. and Canada. Engineers from overseas including Dr. John Knapton and John Emery from England, Dr. Brian Shackel from Australia, and port engineer H. van Leeuwen from the Netherlands influenced early projects. L to R: John Knapton, Brian Shackel and John Emery meet in the early 1990s at NASA in Langley, VA to discuss testing pavers for skid resistance to aircraft tires. 1982—Pier IX (formerly Massey Coal Terminal) Newport News, Virginia—610,000 sf (56,670 m 2 ) was subjected to huge coal piles (for steel making) readied by big bulldozers for loading onto collier ships bound for Europe or elsewhere. PHOTO COURTESY OF UNI-GROUP USA 1983—North Bay, Ontario—150,000 sf (13,935 m 2 ) of streets and sidewalks subject to harsh winters and deicers. PHOTO SOURCE: PORTLAND CEMENT ASSOCIATION 1 6 • I C P I C O M M E M O R AT I V E P U B L I C AT I O N