TY - GEN
T1 - The effect of SAP on volumetric changes and microstructural alterations in PC-GGBS matrices
AU - Almeida, Fernando C.R.
AU - Rostami, Rohollah
AU - Klemm, Agnieszka J.
N1 - Acceptance and AAM requested. ST 26/02/21
AAM: 12m embargo (going by Springer's generic policy: https://www.springer.com/gb/open-access/publication-policies/self-archiving-policy) and made open as embargo expired at time of upload. ET 8/3/21
YYYY only for pub date. ST 26/02/21
^YYYY only in Crossref too. ET 4/3/21
PY - 2020
Y1 - 2020
N2 - Despite their growing popularity in construction, cement-based materials containing ground granulated blast-furnace slag (GGBS) may suffer from various deteriorative actions, including development of early cracks caused by shrinkage processes. Moreover, the degree of GGBS reaction (at later stages) can be limited by lack of space already filled by early products of Portland cement (PC) hydration. In attempt to reduce these negative effects, Superabsorbent polymers (SAP) can be used as internal curing agents and facilitate hydration processes. This paper intends to evaluate and correlate shrinkage behaviour and microstructural features of SAP-GGBS mortars during the first 90 days. Six sets of mortars (with 0% and 50% GGBS) modified by two SAPs were analysed. Autogenous, plastic and drying shrinkages were tested, and microstructural characteristics were analysed by the MIP technique. The experimental results showed significant effect of SAPs on shrinkage reduction in GGBS matrices. The paper argues that deposition of later GGBS hydration products in pores below 20 nm, triggered by SAP water, leads to a relative expansion of SAP-PC-GGBS mortars. In this context, the role of SAPs in GGBS-PC matrices is twofold: firstly, a provision of additional water for hydration and, secondly, a provision of the required space for later products formation.
AB - Despite their growing popularity in construction, cement-based materials containing ground granulated blast-furnace slag (GGBS) may suffer from various deteriorative actions, including development of early cracks caused by shrinkage processes. Moreover, the degree of GGBS reaction (at later stages) can be limited by lack of space already filled by early products of Portland cement (PC) hydration. In attempt to reduce these negative effects, Superabsorbent polymers (SAP) can be used as internal curing agents and facilitate hydration processes. This paper intends to evaluate and correlate shrinkage behaviour and microstructural features of SAP-GGBS mortars during the first 90 days. Six sets of mortars (with 0% and 50% GGBS) modified by two SAPs were analysed. Autogenous, plastic and drying shrinkages were tested, and microstructural characteristics were analysed by the MIP technique. The experimental results showed significant effect of SAPs on shrinkage reduction in GGBS matrices. The paper argues that deposition of later GGBS hydration products in pores below 20 nm, triggered by SAP water, leads to a relative expansion of SAP-PC-GGBS mortars. In this context, the role of SAPs in GGBS-PC matrices is twofold: firstly, a provision of additional water for hydration and, secondly, a provision of the required space for later products formation.
KW - superabsorbent polymers
KW - GGBS
KW - hydration
KW - shrinkage
KW - porosity
U2 - 10.1007/978-3-030-33342-3_11
DO - 10.1007/978-3-030-33342-3_11
M3 - Conference contribution
SN - 9783030333416
T3 - RILEM Bookseries
SP - 97
EP - 105
BT - 3rd International Conference on the Application of Superabsorbent Polymers (SAP) and Other New Admixtures Towards Smart Concrete
A2 - Boshoff, W.P.
A2 - Combrinck, Riaan
A2 - Mechtcherine, Viktor
A2 - Wyrzykowski, Mateusz
PB - Springer
ER -