Quality control of water-reducing admixtures

4.1 Perform air entrainment prediction test. If test results are not within the defined limits, the admixture batch is rejected, and corrective action should be taken. Such an action may include isolation of the abnormal batch and diluting it with regular proper admixture. Dilution ratio is to be set so that the test results will be within the defined limits after dilution.4.2 If the air entrainment prediction test is passed, proceed with the mortar flow test. If test results are not within the defined limits, the admixture batch is rejected, and corrective action should be taken.  4.3 Admixtures passing both tests are allowed for marketing and the admixture performance is guaranteed.
4.1 Perform air entrainment prediction test. If test results are not within the defined limits, the admixture batch is rejected, and corrective action should be taken. Such an action may include isolation of the abnormal batch and diluting it with regular proper admixture. Dilution ratio is to be set so that the test results will be within the defined limits after dilution.
4.2 If the air entrainment prediction test is passed, proceed with the mortar flow test. If test results are not within the defined limits, the admixture batch is rejected, and corrective action should be taken. 
4.3 Admixtures passing both tests are allowed for marketing and the admixture performance is guaranteed.
Fig. 1: Torque curves of two samples (same admixture type) Figure: Chaim V. Israel
Fig. 1: Torque curves of two samples (same admixture type)
Figure: Chaim V. Israel
Fig. 2:  Surface tension of admixture solutions as a function of bubble lifetime Figure: Chaim V. Israel
Fig. 2:  Surface tension of admixture solutions as a function of bubble lifetime
Figure: Chaim V. Israel
Fig. 3: Air entrainment as a function of surface tension Figure: Chaim V. Israel
Fig. 3: Air entrainment as a function of surface tension
Figure: Chaim V. Israel
Fig. 4: Torque curves of three admixture samples Figure: Chaim V. Israel
Fig. 4: Torque curves of three admixture samples
Figure: Chaim V. Israel
Chaim V. Israel: Master of Chemical Engineering Science, Technion - Israel institute of technology (Graduated 2000). 23 years of practical experience with Catalysis, Semiconductors processing, Lime plant operation and products development, Aaggregates concrete admixtures development and quality assurance. Member of an expert committee at the Israeli standard institute.        Questions and comments please to: document.write('' + 'chaimisrael' + '@' + 'yahoo' + '.' + 'com' + '');Chaim V. Israel: Master of Chemical Engineering Science, Technion - Israelisches Institut für Technologie (Abschluss 2000). 23 Jahre praktische Erfahrung in den Bereichen Katalyse, Halb-leiterverarbeitung, Betrieb von Kalkwerken und Produktentwicklung, Entwicklung von Zuschlagstoffen und Betonzusatzmitteln sowie Qualitätssicherung. Mitglied eines Expertenausschusses des israelischen Normungsinstituts.    Fragen und Kommentare bitte an: document.write('' + 'chaimisrael' + '@' + 'yahoo' + '.' + 'com' + '');  
Chaim V. Israel: Master of Chemical Engineering Science, Technion - Israel
institute of technology (Graduated 2000). 23 years of practical experience with Catalysis, Semiconductors processing, Lime plant operation and products development, Aaggregates
concrete admixtures development and quality assurance. Member of an expert committee at the Israeli standard institute.        Questions and comments please to:
Chaim V. Israel: Master of Chemical Engineering Science, Technion - Israelisches Institut für
Technologie (Abschluss 2000). 23 Jahre praktische Erfahrung in den Bereichen Katalyse, Halb-
leiterverarbeitung, Betrieb von Kalkwerken und Produktentwicklung, Entwicklung von Zuschlagstoffen und Betonzusatzmitteln sowie Qualitätssicherung. Mitglied eines Expertenausschusses des israelischen Normungsinstituts.    Fragen und Kommentare bitte an:
 

Measuring the admixture performance by testing the admixture effect on a concrete mix is a procedure that requires the investment of large inputs of skilled manpower and time. This paper presents several test methods that are quick and easy
to perform. The results of these tests allow for rapid and accurate determination of whether the admixture is suitable for use and marketing.

The performance of chemical admixtures is a key factor for successful concrete production and placement. Variations in admixture performance will lead to unstable fresh concrete properties and thus increase the probability of concrete casting failures and customer complaints. Measuring the admixture performance by testing the admixture effect on a concrete mix is a procedure that requires the investment of large inputs of skilled manpower and time, making it difficult to integrate into quality control (QC) applications. A more productive method is required to enable the QC of water-reducing...

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BFT 03/2023

Ressort:  SCIENCE AND RESEARCH
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