【国外标准】 Standard Guide for Measurement of the Rheological Properties of Hydraulic Cementious Paste Using a Rotational Rheometer

4.1 Rheological properties determined using this guide include plastic viscosity and yield stress as defined by the Bingham model and apparent viscosity.4.2 Rheological properties provide information about the workability of hydraulic cementitious paste. As an example, the yield stress and plastic viscosity indicate the behavior of a specific cement paste composition. As another example, the apparent viscosity indicates what energy is required to move the suspension at a given strain rate. This test may be used to measure flowability of a cement paste or the influence of a specific material or combination of materials on flowability.4.3 Rheological properties may be sensitive to the procedure being used. This guide describes procedures that are expected to provide reproducible results.1.1 This guide covers description of several methods to measure the rheological properties of fresh hydraulic cement paste. All methods are designed to determine the yield stress and plastic viscosity of the material using commercially available instruments and the Bingham model. Knowledge of these properties gives useful information on performance of cement pastes in concrete.1.2 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.1.3 This guide offers an organized collection of information or a series of options and does not recommend a specific course of action. This document cannot replace education or experience and should be used in conjunction with professional judgment. Not all aspects of this guide may be applicable in all circumstances. This ASTM standard is not intended to represent or replace the standard of care by which the adequacy of a given professional service must be judged, nor should this document be applied without consideration of a project's many unique aspects. The word “Standard” in the title of this document means only that the document has been approved through the ASTM consensus process.1.4 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.1.5 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.