1. Rationale
The phrase This test method is not intended to be used with lightweight aggregate needs to be modified as it is in conflict with standard practice. For over 40 years, millions of cubic yards of lightweight concrete using ASTM C330 or ASTM C332 Type II aggregate have been placed using the absolute volume method based on relative densities using the 24 hour criteria determined from the present versions of ASTM C127 and C128. In the paper moisture dynamics of lightweight aggregate and concrete published in the proceeding of the sixth international conference on durability of concrete, CANMET/ACI Thessanloniki, Greece June 2003. The authors measured and reported the very slow further rate of absorption of lightweight aggregate after 24 hour absorption. In order to be conservative the sub-committee voted and approved to extend the submersion time to be 72 hours and to have the material stirred once ever 24 hours. This very slow rate of absorption after 24 hours is also reported in chapter 46 lightweight concrete and aggregates in ASTM 169D Significance of Tests and Properties of Concrete and Concrete Making Materials; Editors Lamond J.F. and Pielert J. H.
Keywords
absorption; aggregate; apparent density; apparent relative density; coarse aggregate; density; relative density; specific gravity;
Citing ASTM Standards
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