ASTM pros

Summary The compressive strengths from the concrete cylinders are the main focus of this report although air and proctor tests were also conducted. The tests conducted in the LAOP conform with the standards approved by the American Society of Testing Materials (ASTM) which are briefly described in Appendix A of the report. This report will focus on five admixtures tested on four different Lafarge cements. One of the admixtures was targeted for possible future commercial …

…worst performance with 25-XL at 46.5 MPa. Oddly, the 25-XL had the best 7 day strength. None of the admixtures did a poor job. The largest spread between the best and worst admixture occurred with the St. Constant cement with a difference of 3.5 MPa. This range represents a 7.5 % difference in strength. All of the other cements had a difference of less than 1.7 MPa which means that the difference on most cements fell between 2-4% in strength difference.