Bridgeview, Ill.-based Prairie Material provided self-consolidating concrete for the SCC 2013 workshop at University of Illinois, Chicago (UIC).
With help from UIC engineering students, representatives from BASF and W.R. Grace demonstrated approved ASTM methods to test critical properties of SCC: filling ability, passing ability, and segregation resistance.
Van Bui of BASF demonstrates an SCC stability test with an inverted slump cone. Bui developed the process that uses a small penetration apparatus to mimic the movement of coarse aggregates through the concrete mix. The cone can then be used to conduct a slump flow test.
Attendees of the Chicago event watch as a J-ring test measures the passing ability of a fresh SCC mix.
Ara Jeknavorian, W.R. Grace research fellow, explains how the company’s rheometer accurately tests SCC viscosity and yield.
The rheometer relays test data to a laptop computer, to analyze the SCC mix design in less than one minute.
UIC engineering students built a plexiglass U-form to demonstrate how SCC can be used to fill complicated formwork. (Students were also responsible for cleaning out the form after the demonstration was done.)
Joe Daczko, BASF product manager, measures each column to check the SCC’s ability to flow and fill the form. In this demonstration, the column closest to the truck measured 47 ½ inches; the far column was 45 inches high.
The SCC mix delivered by Prairie Material was free of bug holes on the surface. However, Daczko cautioned, if the concrete is poured too quickly, it can result in voids that aren’t visible on the surface. “SCC is not a cure-all,” he said. “You still have to pour it correctly according to the form dimensions and mix characteristics.”