Cement and concrete research vol:31 issue:7 pages:1027-1031
This paper presents the results of a European round robin test on air void analysis on hardened concrete (SMT-EC-research project - Contract No. SMT4-CT95-2006). Thirteen laboratories in Europe from seven countries participated in the intercomparison test of which seven used a manual method and six an automated measurement system. The results indicate that the results obtained with measuring methods using image analysis (IA) techniques all statistically lie in the group of all measurement results. The automated methods can be problematic when a high amount of porous sand grains is present in the concrete. A second disadvantage of these automated methods is that it is not possible with the current methods being used to measure the paste content of the sample. (C) 2001 Elsevier Science Ltd. All rights reserved.