Title: Modeling of Internal Curing with SAP at Meso- and Macro-Level

Author(s): M. Wyrzykowski, P. Lura, and D. Gawin

Publication: Symposium Paper

Volume: 290

Issue:

Appears on pages(s): 1-12

Keywords: Concrete, internal curing, poromechanical modeling, superabsorbent polymers, water migration

DOI: 10.14359/51684181

Date: 9/14/2012

Abstract:
Internal curing by means of superabsorbent polymers (SAP) is an efficient method for providing additional curing water in high performance concrete with low w/c. In order to fully use the potential of internal curing reservoirs, the water needs to be supplied possibly uniformly in the whole volume of hydrating cement paste and moreover at rates sufficiently high to compensate for the self-desiccation. At the same time, it is of importance to predict how the internal curing process will influence the overall material behavior at the macroscopic level. In this work, the investigation of the aforementioned phenomena is performed at two scales using poromechanical modeling. First, a mechanistic model of cementitious material is applied for the analysis of internal curing at the meso-level to describe water transport from the reservoirs to the surrounding cement paste. The meso-level simulations confirm that curing water can be practically uniformly and instantaneously distributed within the volume of the surrounding paste at the early stages of hydration. Second, based on this information, a source term due to internal curing is introduced at the macro-level, enabling description of the influence of the SAP on such phenomena as self-desiccation and autogenous shrinkage. This approach provides a very good agreement with the experimental data.