Analysis of the ASTM Round-Robin Test on Particle Size Distribution of Portland Cement: Phase 1.

摘要

Particle size distribution (PSD) is an essential property of cement. The only standard method to measure the PSD of cement, namely ASTM C115 (1) is limited in scope; this standard describes a method for determining 'fineness' with a lower size detection limit of 7.5 um. As there is not standard procedure covering the whole range of cement PSD, the implementation of different measurement methods varies widely within the industry. In general, the round-robin results summarized here have demonstrated the high variability between participants using instruments based on the same physical principles. ASTM committee CO1.25.01 sponsored a round-robin test to measure the PSD of cement. The aim of the current report is to analyze the data generated during those tests and to summarize the various approaches available to measure the PSD of cement. The analysis of the data is conducted in two parts. In the first part, an attempt is made to establish a reference distribution using a standard cement powder (SRM 114p). This is followed up by a comparison of the round-robin data in order to initiate discussion on developing a standard test method for cement PSD to be submitted for ASTM consideration. The report provides all raw data collected during the round robin tests, and the results of a statistical analysis of the collected data.