TY - JOUR
T1 - Properties of additively manufactured geopolymer incorporating mineral wollastonite microfibers
AU - Bong, Shin Hau
AU - Nematollahi, Behzad
AU - Xia, Ming
AU - Ghaffar, Seyed Hamidreza
AU - Pan, Jinlong
AU - Dai, Jian Guo
N1 - Funding Information:
The authors acknowledge the support from the Australian Research Council Linkage Infrastructure Grant LE170100168, Discovery Project DP210101680 and Discovery Early Career Researcher Award DE180101587. Further, the authors acknowledge the Victoria-Jiangsu Program for Technology and Innovation R&D grant funded by the Victoria Department of Jobs, Precincts and Regions in Australia, and the Jiangsu Department of Science and Technology in China.
Publisher Copyright:
© 2022 Elsevier Ltd
PY - 2022/5/9
Y1 - 2022/5/9
N2 - Integration of reinforcement in the 3D concrete printing (3DCP) process is a major challenge. As a possible solution, the addition of short synthetic/metallic fibers directly to a fresh mixture before extrusion has been investigated in previous studies. However, the use of natural/inorganic microfibers such as wollastonite as reinforcement for 3DCP has received less attention. Wollastonite is substantially cheaper and more environmentally friendly than synthetic/metallic fibers. To fill this knowledge gap, this study reports a systematic approach to enhance the flexural strength of a 3D-printed geopolymer by the addition of wollastonite microfiber. The effect of different replacement levels of wollastonite (0, 5, 10, 15, 20, and 30% by weight of sand) on setting time and mechanical properties of several mixtures were evaluated to identify the optimum wollastonite content. The printing performances, rheological properties, and mechanical strengths of the optimum mixture were then evaluated and compared with the control mixture (without wollastonite). The results showed that at 10% replacement level, the static yield stress and thixotropy property of the mixture were enhanced, which is desirable for the superior printability of the mixture. In addition, the flexural strength of the mixture incorporating 10% wollastonite was superior to the control mixture, whereas the compressive strength was not changed. The use of mineral wollastonite microfibers as a low-cost and environmentally friendly reinforcement for 3DCP is experimentally established in this study.
AB - Integration of reinforcement in the 3D concrete printing (3DCP) process is a major challenge. As a possible solution, the addition of short synthetic/metallic fibers directly to a fresh mixture before extrusion has been investigated in previous studies. However, the use of natural/inorganic microfibers such as wollastonite as reinforcement for 3DCP has received less attention. Wollastonite is substantially cheaper and more environmentally friendly than synthetic/metallic fibers. To fill this knowledge gap, this study reports a systematic approach to enhance the flexural strength of a 3D-printed geopolymer by the addition of wollastonite microfiber. The effect of different replacement levels of wollastonite (0, 5, 10, 15, 20, and 30% by weight of sand) on setting time and mechanical properties of several mixtures were evaluated to identify the optimum wollastonite content. The printing performances, rheological properties, and mechanical strengths of the optimum mixture were then evaluated and compared with the control mixture (without wollastonite). The results showed that at 10% replacement level, the static yield stress and thixotropy property of the mixture were enhanced, which is desirable for the superior printability of the mixture. In addition, the flexural strength of the mixture incorporating 10% wollastonite was superior to the control mixture, whereas the compressive strength was not changed. The use of mineral wollastonite microfibers as a low-cost and environmentally friendly reinforcement for 3DCP is experimentally established in this study.
KW - 3D concrete printing
KW - Mechanical properties
KW - One-part geopolymer
KW - Rheology
KW - Wollastonite
UR - http://www.scopus.com/inward/record.url?scp=85127309422&partnerID=8YFLogxK
U2 - 10.1016/j.conbuildmat.2022.127282
DO - 10.1016/j.conbuildmat.2022.127282
M3 - Journal article
AN - SCOPUS:85127309422
SN - 0950-0618
VL - 331
JO - Construction and Building Materials
JF - Construction and Building Materials
M1 - 127282
ER -