| Title |
Long term mechanical performance of nano-engineered high volume fly ash concrete |
| ID_Doc |
10963 |
| Authors |
Herath, C; Gunasekara, C; Law, DW; Setunge, S |
| Title |
Long term mechanical performance of nano-engineered high volume fly ash concrete |
| Year |
2021 |
| Published |
|
| DOI |
10.1016/j.jobe.2021.103168 |
| Abstract |
High Volume Fly Ash (HVFA) concrete is a sustainable construction material which can act as a viable alternative to Portland cement (PC) concrete. This study investigates the long-term mechanical performance of two unique HVFA concrete mixes, 65% and 80% cement replacements, incorporating hydrated lime, up to 18%, and 3% nano silica. HVFA-65 concrete achieved compressive strength values increasing from 32 to 73 MPa, from 7 to 450 day while HVFA-80 displayed a strength increase from 22 to 71 MPa in the same period. The flexural strength of HVFA-65 concrete increased from 3.6 to 8.7 MPa while the splitting tensile strength and elastic modulus gave values of 2.7-5.8 MPa and 30.3-40.5 GPa, respectively. Meanwhile, HVFA-80 concrete achieved flexural strengths of 2.7-8.7 MPa, splitting tensile strengths of 1.6-5.0 MPa and an elastic modulus of 28.9-37.0 GPa. Analysis of paste samples identified the presence of 11%, 3.2%, 5.3% and 2.1% higher concentrations of Por-tlandite within the HVFA-65 system at 7, 28, 90 and 450 days respectively, indicating a high availability of portlandite for the pozzolanic reaction of the fly ash. In microstructural investigation, HVFA-65 concrete dis -played a denser gel matrix and stronger bond within the interfacial transition zone (ITZ) boundary compared to HVFA-80 at all ages. In addition, a statistical regression analysis conducted to predict relationships between long term mechanical properties of HVFA concrete are compared with existing design equations available in Australian Standards and ACI codes. |
| Author Keywords |
HVFA concrete; Mechanical properties; Chemistry; Microstructure; Sustainability |
| Index Keywords |
Index Keywords |
| Document Type |
Other |
| Open Access |
Open Access |
| Source |
Science Citation Index Expanded (SCI-EXPANDED) |
| EID |
WOS:000697180400003 |
| WoS Category |
Construction & Building Technology; Engineering, Civil |
| Research Area |
Construction & Building Technology; Engineering |
| PDF |
|