Title:
Interaction between Accelerating Admixtures and Portland
Cement for Shotcrete: The Influence of the Admixture’s
Chemical Base and the Correlation between Paste Tests
and Shotcrete Performance
Author(s):
Luiz R. Prudencio, Jr., Hugo S. Armelin, and Paulo Helene
Publication:
Materials Journal
Volume:
93
Issue:
6
Appears on pages(s):
619-628
Keywords:
accelerating agents; admixtures; field tests; portland
cement; shotcrete.
DOI:
10.14359/9869
Date:
11/1/1996
Abstract:
This study analyzes the correspondence between initial and final setting times measured using Gillmore needles (commonly specified for shotcrete) with shooting stiffness-measured Proctor needles and compressive strength at early ages (evaluated using nondestructive penetration tests). Two different types of accelerating admixtures (carbonate and aluminate based) and two different types ofportland cements were used in the tests on cement paste and shotcrete. Results indicate a difference in performance between the different types of accelerating admixtures tested. Also, it was found that although tests on cement paste show adequate sensitivity to accelerator type and addition rate, the correspondence with setting time and early strength gain in shotcrete is still very poor: