Westminster, Colorado June 12, API Cooperative Testing Preliminary Report on Compressive Strength

2012 Protocol Test Protocol in 2012 matched previous years: –Cubes: 100F 8 hours 140F 8 hours 100F 24 hours –UCA: 100F 8 hours 100F 24 hours Time to 50 and 500 psi Changes to protocol in 2012 –As in 2010, eliminated 20 minute pre-conditioning requirement –Eliminated the requirement to calculate cube density –Continue to request pictures of load frames utilized Further analysis to be included in Final CS Report in New Orleans –CS results tied to load frame group: Manual vs Digital –Evaluation of UCA Transit Time –Service Companies and other vs. Cement Plants –Load frame verification using low strength Burst Disks at known failure values

100F-8hr Cube 100F-24hr Cube 140F-8hr Cube 100F-8hr UCA 100F-24hr UCA AVG Std Dev CV With +/- 2 Standard Deviations Deleted AVG Std Dev CV Preliminary Strength Data

AVERAGESTD DEVCV F - 8 hr Cube F - 24 hr Cube F -8 hr Cube hr UCA hr UCA Compressive Strength Comparison 2010 vs (preliminary data)

UCA Time to 50 & 500 psi (preliminary data) 50 psi (min) 500 psi (min) AVG Std Dev 2769 CV With +/- 2 Std Deviation Deleted AVG Std Dev 2347 CV

2012 UCA and Cube CS sorted by value (preliminary data)

8 hr Cube8 hr UCAChange24 hr Cube24 hr UCAChange (194) (92) (165) (208) (203) (164) (198) 2000 to 2012 UCA vs Cubes Average Compressive Strength (preliminary data)

CV Comparison 2000 to 2012 (preliminary data)

2012 Preliminary Conclusions High variability continues with 8 hr cube test. Initial CVs for all test categories continues to creep up. Historical relationships between cubes and UCA holds true. Good response to request for load frame pictures will permit further analysis. Let’s see what full data set reveals after more in depth analysis.

Thank you! Comments and Questions?