Title:
UHPC Fresh Chloride Limit Testing
Author(s):
Raid Alrashidi
Publication:
Web Session
Volume:
ws_S22_RaidAlrashidi.pdf
Issue:
Appears on pages(s):
Keywords:
DOI:
Date:
3/28/2022
Abstract:
The presence of chloride ions is one of the most widespread causes of corrosion initiation in reinforcing steel in concrete. Trace chlorides present in cementitious materials or admixtures typically result in very low fresh chloride contents in normal strength concrete that do not present a danger of corrosion. Ultra-high performance concrete mixture designs however use much higher dosages of cementitious materials and admixtures that can result in non-negligible fresh chloride contents as measured in mass of chlorides per volume of concrete. These high chloride values are likely to occur more frequently in the future as more UHPC mixtures are made with locally available materials and alternative cementitious materials and may result in concrete mixtures failing to meet specifications for fresh chloride content limits that are based on mixture proportions used in normal strength concrete mixtures. In this study, the chloride threshold for fresh concrete was measured in this study using a slightly modified version of the accelerated test EN 480-14. The water-soluble and acid-soluble chloride ion content of UHPC mixtures tested were measured according to ASTM C1218 and ASTM C1152 to determine the bound chlorides and fresh chloride limits for corrosion. This presentation will discuss the issue facing UHPC producers, the test methods used and results of corrosion testing performed, recommend fresh chloride limits for UHPC, and ultimately reassure users of the durability of UHPC.