TY - JOUR
T1 - Can superabsorbent polymers be used as rheology modifiers for cementitious materials in the context of 3D concrete printing?
AU - Chen, Yu
AU - Liang, Minfei
AU - Zhang, Yu
AU - Li, Zhenming
AU - Šavija, Branko
AU - Schlangen, Erik
AU - Çopuroğlu, Oğuzhan
PY - 2023
Y1 - 2023
N2 - Autogenous shrinkage may be a critical issue concerning the use of limestone-calcined clay-cement (LC3) in high-performance concrete and 3D printable cementitious materials, which have relatively low water to binder (W/B) ratio. Adding an internal curing agent, i.e., superabsorbent polymer (SAP), could be a viable solution in this context. However, employing SAP (without adding additional water) may also influence the fresh properties of LC3 composites by increasing yield stress and viscosity, which may be beneficial for 3D printability. Therefore, this study attempts to use SAP as a rheology modifying admixture with the aim of investigating the impact of SAP on flow behavior, structural build-up, hydration kinetics, compressive strength, and autogenous shrinkage of LC3 pastes with a fixed W/B (0.3). In addition, hydroxypropyl methylcellulose (a typical rheology/viscosity modifier in 3D printable cementitious materials) was also employed in two mixtures to compare their effects. Results show that adding SAP increases the dynamic yield stress and the apparent viscosity, as well as structural build-up and hydration, but decreases the compressive strength at 3, 7 and 28 days. Furthermore, using SAP (especially 0.2 wt% SAP) not only promotes the early-age expansion but also effectively mitigates the autogenous shrinkage of LC3 pastes for up to 7 days. Overall, the obtained results indicated that SAP could act as a promising rheology modifier for the development of 3D printable cementitious materials.
AB - Autogenous shrinkage may be a critical issue concerning the use of limestone-calcined clay-cement (LC3) in high-performance concrete and 3D printable cementitious materials, which have relatively low water to binder (W/B) ratio. Adding an internal curing agent, i.e., superabsorbent polymer (SAP), could be a viable solution in this context. However, employing SAP (without adding additional water) may also influence the fresh properties of LC3 composites by increasing yield stress and viscosity, which may be beneficial for 3D printability. Therefore, this study attempts to use SAP as a rheology modifying admixture with the aim of investigating the impact of SAP on flow behavior, structural build-up, hydration kinetics, compressive strength, and autogenous shrinkage of LC3 pastes with a fixed W/B (0.3). In addition, hydroxypropyl methylcellulose (a typical rheology/viscosity modifier in 3D printable cementitious materials) was also employed in two mixtures to compare their effects. Results show that adding SAP increases the dynamic yield stress and the apparent viscosity, as well as structural build-up and hydration, but decreases the compressive strength at 3, 7 and 28 days. Furthermore, using SAP (especially 0.2 wt% SAP) not only promotes the early-age expansion but also effectively mitigates the autogenous shrinkage of LC3 pastes for up to 7 days. Overall, the obtained results indicated that SAP could act as a promising rheology modifier for the development of 3D printable cementitious materials.
KW - Autogenous shrinkage
KW - Hydration kinetics
KW - Limestone-calcined clay-cement
KW - Rheology modifier
KW - Structural build-up
KW - Superabsorbent polymer
UR - http://www.scopus.com/inward/record.url?scp=85148542185&partnerID=8YFLogxK
U2 - 10.1016/j.conbuildmat.2023.130777
DO - 10.1016/j.conbuildmat.2023.130777
M3 - Article
AN - SCOPUS:85148542185
SN - 0950-0618
VL - 371
JO - Construction and Building Materials
JF - Construction and Building Materials
M1 - 130777
ER -