TY - JOUR
T1 - Role of aggregate and fibre in strength and drying shrinkage of alkali-activated slag mortar
AU - Chen, Weiwei
AU - Xie, Yu
AU - Li, Binxu
AU - Li, Bo
AU - Wang, Juan
AU - Thom, Nicholas
N1 - Funding Information:
The authors wish to acknowledge the financial support from the Zhejiang Provincial Natural Science Foundation of China (Grant No.: LGF19E080008 ) and Ningbo Municipal Bureau of Science and Technology (No.: 2019B10048 ). The Zhejiang Provincial Department of Science and Technology is acknowledged for this research under its Provincial Key Laboratory Programme (No.: 2020E10018 ). The technical support from the New Materials Institute and Civil Engineering Laboratory at the University of Nottingham Ningbo China is also greatly acknowledged.
Funding Information:
The authors wish to acknowledge the financial support from the Zhejiang Provincial Natural Science Foundation of China (Grant No.: LGF19E080008) and Ningbo Municipal Bureau of Science and Technology (No.: 2019B10048). The Zhejiang Provincial Department of Science and Technology is acknowledged for this research under its Provincial Key Laboratory Programme (No.: 2020E10018). The technical support from the New Materials Institute and Civil Engineering Laboratory at the University of Nottingham Ningbo China is also greatly acknowledged.
Publisher Copyright:
© 2021 Elsevier Ltd
PY - 2021/9/13
Y1 - 2021/9/13
N2 - This paper presents an investigation on the influences of aggregate-to-binder (A/B) ratio, aggregate size, polypropylene (PP) and steel fibre dosages on the strength and drying shrinkage of alkali-activated slag mortar (AASM). The results indicate that increasing either A/B ratio up to 2.0 or aggregate size up to 1.18 mm first enhances both compressive and flexural strengths of AASM, followed by a reduction as they further increase. This is mainly attributed to the densified aggregate skeleton formed inside AASM. Furthermore, increasing the A/B ratio decreases the moisture loss in AASM and subsequently decreases their drying shrinkage. The use of coarse sand (e.g. 1.18–2.36 mm) enhances the volumetric stability of AASM prepared with the same binder content. For fibre reinforced AASM, the addition of PP fibres reduces the compressive strength of AASM, while the addition of steel fibres has a positive impact. The use of PP fibres not only causes fibre cluster problem, but also creates the weakened interfaces between fibres and binder. Increasing the PP or steel fibre dosage can enhance the flexural strength of AASM, particularly for steel fibres as they have a better bond with the matrix. Incorporation of PP or steel fibres can reduce the drying shrinkage of AASM. As compared to PP fibres, steel fibres are more effective in restraining the drying shrinkage of AASM.
AB - This paper presents an investigation on the influences of aggregate-to-binder (A/B) ratio, aggregate size, polypropylene (PP) and steel fibre dosages on the strength and drying shrinkage of alkali-activated slag mortar (AASM). The results indicate that increasing either A/B ratio up to 2.0 or aggregate size up to 1.18 mm first enhances both compressive and flexural strengths of AASM, followed by a reduction as they further increase. This is mainly attributed to the densified aggregate skeleton formed inside AASM. Furthermore, increasing the A/B ratio decreases the moisture loss in AASM and subsequently decreases their drying shrinkage. The use of coarse sand (e.g. 1.18–2.36 mm) enhances the volumetric stability of AASM prepared with the same binder content. For fibre reinforced AASM, the addition of PP fibres reduces the compressive strength of AASM, while the addition of steel fibres has a positive impact. The use of PP fibres not only causes fibre cluster problem, but also creates the weakened interfaces between fibres and binder. Increasing the PP or steel fibre dosage can enhance the flexural strength of AASM, particularly for steel fibres as they have a better bond with the matrix. Incorporation of PP or steel fibres can reduce the drying shrinkage of AASM. As compared to PP fibres, steel fibres are more effective in restraining the drying shrinkage of AASM.
KW - Aggregate size
KW - Aggregate/binder ratio
KW - Alkali-activated slag mortar
KW - Drying shrinkage
KW - PP fibre
KW - Steel fibre
KW - Strength
UR - http://www.scopus.com/inward/record.url?scp=85108451306&partnerID=8YFLogxK
U2 - 10.1016/j.conbuildmat.2021.124002
DO - 10.1016/j.conbuildmat.2021.124002
M3 - Article
AN - SCOPUS:85108451306
SN - 0950-0618
VL - 299
JO - Construction and Building Materials
JF - Construction and Building Materials
M1 - 124002
ER -