New method for determination of absorption capacity of internal curing agents

Accurate assessment of absorption capacity (k) of internal curing agents is necessary to properly proportion cement-based mixtures and to measure their effectiveness in mitigating autogenous shrinkage. Standard methods for quantifying absorption capacity, such as those for coarse and fine aggregate, are not appropriate for the highly absorptive, finely divided materials often used for internal curing. Here, it is demonstrated that the absorption capacity of internal curing materials may be determined from early age heat evolution data measured through isothermal calorimetry. An example application, using pulp fibers as internal curing agents, is used to demonstrate the utility of the method.