Investigation of Accelerated Methods for the Determination of Available Alkali in Pozzolans.

摘要

The procedure specified in acceptance testing of pozzolans for the determination of the available alkali released by a pozzolan requires the lime-pozzolan paste to be stored for a period of 28 days prior to test. In order to investigate the possibility of reducing the storage time of the paste prior to test, six pozzolans were tested for available alkali release rate by subjecting the paste to three conditions of storage time and/or temperature. The three conditions were as follows: (a) Condition 1, Standard Condition, 28 days at 38 C; (b) Condition 2, seven days at 38 C; (c) Condition 3, seven days at 65.5 C. In order to reduce the storage time of the lime-pozzolan paste to seven days, storage Condition 3 with a maximum limit of 1.0 percent available alkali is recommended as an optional method for the acceptance testing of pozzolan.