TY - JOUR
T1 - Strain-rate-dependent performance of cementitious nanocomposites
T2 - nanosilica and the role of dispersion
AU - Tourani, Navid
AU - Sagoe-Crentsil, Kwesi
AU - Duan, Wenhui
N1 - Funding Information:
The authors are grateful for the financial support of the Australian Research Council ( IH150100006 and LE150100058 ) in conducting this study and acknowledge the use of facilities within the Monash Centre for Electron Microscopy (MCEM) and Monash GeoExtremes (MGE) Lab.
Publisher Copyright:
© 2022 Elsevier Ltd
PY - 2022/11
Y1 - 2022/11
N2 - This study focused on the strain-rate-dependent effects of powder nanosilica (PNS) and its dispersion on the mechanical properties, fracture pattern and energy absorption of cement composites by investigating its quasi-static strain rate (QS), intermediate strain rate (ISR) and high strain rate (HSR) behaviour. To this end, a Split Hopkinson Pressure Bar equipped with a high-speed camera was utilised. Additionally, SEM and dispersion investigations were conducted to study the microstructural effects of PNS and its dispersion state, respectively, and link them to its mechanical contributions. We found that, although NS significantly improved QS properties, it negatively affected the dynamic (ISR and HSR) performance of the cement paste. These negative dynamic effects were found to be primarily controlled by the dispersion state of the nanomaterial. Although dispersing the PNS partially ameliorated the negative dynamic effects, it did not fully resolve them. The dispersion effect was more pronounced under HSR loading.
AB - This study focused on the strain-rate-dependent effects of powder nanosilica (PNS) and its dispersion on the mechanical properties, fracture pattern and energy absorption of cement composites by investigating its quasi-static strain rate (QS), intermediate strain rate (ISR) and high strain rate (HSR) behaviour. To this end, a Split Hopkinson Pressure Bar equipped with a high-speed camera was utilised. Additionally, SEM and dispersion investigations were conducted to study the microstructural effects of PNS and its dispersion state, respectively, and link them to its mechanical contributions. We found that, although NS significantly improved QS properties, it negatively affected the dynamic (ISR and HSR) performance of the cement paste. These negative dynamic effects were found to be primarily controlled by the dispersion state of the nanomaterial. Although dispersing the PNS partially ameliorated the negative dynamic effects, it did not fully resolve them. The dispersion effect was more pronounced under HSR loading.
KW - Digital image correlation
KW - Dispersion
KW - High strain rate
KW - Mechanical properties
KW - Powder nanosilica
KW - SEM
KW - Split Hopkinson Pressure Bar
UR - http://www.scopus.com/inward/record.url?scp=85137155249&partnerID=8YFLogxK
U2 - 10.1016/j.cemconres.2022.106966
DO - 10.1016/j.cemconres.2022.106966
M3 - Article
AN - SCOPUS:85137155249
SN - 0008-8846
VL - 161
JO - Cement and Concrete Research
JF - Cement and Concrete Research
M1 - 106966
ER -