TY - JOUR
T1 - Strain-hardening alkali-activated fly ash/slag composites with ultra-high compressive strength and ultra-high tensile ductility
AU - Lao, Jian Cong
AU - Huang, Bo Tao
AU - Fang, Yi
AU - Xu, Ling Yu
AU - Dai, Jian Guo
AU - Shah, Surendra P.
N1 - Funding Information:
This study was supported by the Guangdong Province R&D Plan for Key Areas (No. 2019B111107002 ), and The Hong Kong Polytechnic University through the Research Institute of Land and Space (No. 1-CD7D ) and the Research Institute for Sustainable Urban Development (No. 1-BBWE ). Jian-Cong Lao and Bo-Tao Huang would like to acknowledge the support by the Hong Kong Innovation and Technology Fund (No. ITS/077/18FX ) through the Research Talent Hub.
Publisher Copyright:
© 2022 Elsevier Ltd
PY - 2023/3
Y1 - 2023/3
N2 - This study designed and developed strain-hardening alkali-activated fly ash/slag composites (SH-AAFSC) with both ultra-high compressive strength and ultra-high tensile ductility for the first time. The developed SH-AAFSC showed a compressive strength of 94.4–180.7 MPa and a tensile strain capacity of 8.1–9.9 %, which successfully pushed the performance envelope of alkali-activated materials. A multi-scale investigation was conducted to get an in-depth understanding of the obtained mechanical properties. Results showed that higher GGBS content increased the Ca/Si ratio of C(N)ASH, leading to a further refined microstructure with reduced porosity. As w/p ratio decreased from 0.27 to 0.22, the compressive strength significantly increased but the tensile ductility slightly decreased. Notably, a strong linear relationship was observed between fiber-bridging strength and the average elastic modulus of matrix obtained from nanoindentation. The study provided an avenue to produce SH-AAFSC towards ultra-high compressive strength and tensile ductility, which are promising for resilient and sustainable infrastructures.
AB - This study designed and developed strain-hardening alkali-activated fly ash/slag composites (SH-AAFSC) with both ultra-high compressive strength and ultra-high tensile ductility for the first time. The developed SH-AAFSC showed a compressive strength of 94.4–180.7 MPa and a tensile strain capacity of 8.1–9.9 %, which successfully pushed the performance envelope of alkali-activated materials. A multi-scale investigation was conducted to get an in-depth understanding of the obtained mechanical properties. Results showed that higher GGBS content increased the Ca/Si ratio of C(N)ASH, leading to a further refined microstructure with reduced porosity. As w/p ratio decreased from 0.27 to 0.22, the compressive strength significantly increased but the tensile ductility slightly decreased. Notably, a strong linear relationship was observed between fiber-bridging strength and the average elastic modulus of matrix obtained from nanoindentation. The study provided an avenue to produce SH-AAFSC towards ultra-high compressive strength and tensile ductility, which are promising for resilient and sustainable infrastructures.
KW - Alkali-activated composites
KW - Alkali-activated fly ash/slag
KW - Engineered Cementitious Composites (ECC)
KW - Engineered Geopolymer Composites (EGC)
KW - Geopolymer
KW - Strain-Hardening Cementitious Composites (SHCC)
KW - Strain-Hardening Geopolymer Composites (SHGC)
KW - Ultra-High-Performance Geopolymer Concrete (UHPGC)
UR - http://www.scopus.com/inward/record.url?scp=85145018179&partnerID=8YFLogxK
U2 - 10.1016/j.cemconres.2022.107075
DO - 10.1016/j.cemconres.2022.107075
M3 - Journal article
AN - SCOPUS:85145018179
SN - 0008-8846
VL - 165
JO - Cement and Concrete Research
JF - Cement and Concrete Research
M1 - 107075
ER -