TY - JOUR
T1 - Application of powdered bio-composites in the field of self-compacting concrete
T2 - A review
AU - Wang, Jiangjiang
AU - Huang, Ziheng
AU - Xia, Jun
N1 - Funding Information:
Acknowledgements are due to the sponsorship of this study by an external research project funded by Sika (China) Co. Ltd., through project TTC- RP0016 - Eco-Friendly Self-Compacting Concretes for Precast Elements in China. The research findings reported herein are those of the authors alone and not necessarily the views of sponsoring agencies.
Publisher Copyright:
© 2022 Elsevier Ltd
PY - 2022/9/5
Y1 - 2022/9/5
N2 - Cement manufacture accounts for 5% of worldwide carbon dioxide emissions, resulting in significant environmental issues, and using supplemental cementitious materials (SCM) is an efficient strategy to minimise cement consumption. Self-compacting concrete (SCC) often relies on high amounts of binder and chemical additives to maintain workability. Thus, reducing the embodied carbon of SCC materials becomes essential for its wider application. Powdered bio-composites (PBCs), such as rice husk ash (RHA), bagasse ash (BA), palm oil fuel ash (POFA), groundnut shell ash (GSA), and eggshell ash (ESA), can be utilised as SCM for SCC. This paper systematically reviewed the physical properties, chemical properties, and heat treatment methods of five types of PBCs and their impacts after replacing cement in SCC. The review disclosed that heat treatment could effectively reduce the value of loss on ignition (LOI), thus ensuring the activity of PBCs. High-temperature, short-duration incineration or low-temperature incineration for a long time can be effective. The review revealed that adding the five types of PBCs will reduce the workability of SCC, and RHA has the greatest negative impact. Segregation occurs when the cement replacement rate with RHA exceeds 20%. All five types of PBCs improve the mechanical properties of SCC to a certain extent after replacement. The preferred replacement rates are 5%-20% for RHA, BA and GSA, while for POFA the preferred rate could exceed 30%. The preferred rate is not conclusive for Eggshell ash, as it may lead to either positive or slightly negative impacts regarding compressive strength. In addition, adding an appropriate amount of PBCs will increase the durability of hardened SCC. The summarised impacts were also correlated with the microstructure of SCC through various analysis tools. The paper reveals the current gaps in applying PBCs in SCC and proposes strategies to design environmentally friendly SCC containing PBCs.
AB - Cement manufacture accounts for 5% of worldwide carbon dioxide emissions, resulting in significant environmental issues, and using supplemental cementitious materials (SCM) is an efficient strategy to minimise cement consumption. Self-compacting concrete (SCC) often relies on high amounts of binder and chemical additives to maintain workability. Thus, reducing the embodied carbon of SCC materials becomes essential for its wider application. Powdered bio-composites (PBCs), such as rice husk ash (RHA), bagasse ash (BA), palm oil fuel ash (POFA), groundnut shell ash (GSA), and eggshell ash (ESA), can be utilised as SCM for SCC. This paper systematically reviewed the physical properties, chemical properties, and heat treatment methods of five types of PBCs and their impacts after replacing cement in SCC. The review disclosed that heat treatment could effectively reduce the value of loss on ignition (LOI), thus ensuring the activity of PBCs. High-temperature, short-duration incineration or low-temperature incineration for a long time can be effective. The review revealed that adding the five types of PBCs will reduce the workability of SCC, and RHA has the greatest negative impact. Segregation occurs when the cement replacement rate with RHA exceeds 20%. All five types of PBCs improve the mechanical properties of SCC to a certain extent after replacement. The preferred replacement rates are 5%-20% for RHA, BA and GSA, while for POFA the preferred rate could exceed 30%. The preferred rate is not conclusive for Eggshell ash, as it may lead to either positive or slightly negative impacts regarding compressive strength. In addition, adding an appropriate amount of PBCs will increase the durability of hardened SCC. The summarised impacts were also correlated with the microstructure of SCC through various analysis tools. The paper reveals the current gaps in applying PBCs in SCC and proposes strategies to design environmentally friendly SCC containing PBCs.
KW - Agricultural by-products
KW - Durability
KW - Fresh properties
KW - Mechanical properties
KW - Pozzolan
KW - SCC
KW - Supplementary cementitious material
UR - http://www.scopus.com/inward/record.url?scp=85134299266&partnerID=8YFLogxK
U2 - 10.1016/j.conbuildmat.2022.128318
DO - 10.1016/j.conbuildmat.2022.128318
M3 - Review article
AN - SCOPUS:85134299266
SN - 0950-0618
VL - 346
JO - Construction and Building Materials
JF - Construction and Building Materials
M1 - 128318
ER -