Evaluation of Cement Paste Cylinder Preparation Methods for Mechanical Property Measurements

Abstract

Abstract Testing cement paste (CP) cylinders for thermal, mechanical, or both properties has gained some recent traction, with thermal methods (e.g., the recently completed ASTM C1753) being more developed than mechanical property assessments. CP contains water, cementitious materials, and sometimes admixtures; no sand or aggregates. Currently there is no standard production method for CP cylinders. As such, the objectives of this article are to assess the variability of CP mechanical properties from multiple methods and then recommend a CP cylinder preparation method considering overall properties and variability. The recommended method prepares specimen tops in a similar manner to one common method for concrete cylinders (i.e., strike off the specimen top). The rationale for selecting this approach was this method produced essentially the same average compressive strength as existing approaches but with slightly less variability and no extra effort. The proposed method had compressive strength coefficients of variations of 17 % or less when specimens were tested within 0.5 hours of removal from moist curing. The proposed method is able to produce specimens with density and moisture content coefficients of variation of less than 1 %.