Slump and Air: The traditional way vs. the RheoTEC™ Z-60 way
Figures 1 and 2 compare and contrast the traditional way versus the new way of managing workability retention, respectively.
Figure 1 shows the traditional way of re-tempering with water and its impact on workability, air content and 1-day compressive strength. As workability decreases so does the air content. The addition of water increases workability and air content. However, the initial re-tempering results in a 32% decrease in compressive strength. Additional retempering through 90 minutes reduced air content and further diminished concrete compressive strength (note that ASTM C 94 only allows a one time addition of water). Re-tempering is one of the primary causes of concrete inconsistency.
Figure 2 shows the same concrete mixture and the impact of the new RheoTEC admixture on workability, air content and 1-day compressive strength. With RheoTEC, concrete performance is more consistent, making the concrete producer more efficient.
