TY - JOUR
T1 - Thermal and mechanical properties of alkali-activated slag paste, mortar and concrete utilising seawater and sea sand
AU - Li, Ying Lei
AU - Zhao, Xiao Ling
AU - Singh Raman, R. K.
AU - Al-Saadi, Saad
PY - 2018/1/20
Y1 - 2018/1/20
N2 - This paper presents an experimental study on the thermal properties of alkali-activated slag paste, mortar and concrete utilising seawater and sea sand exposed to elevated temperature. The thermal properties of paste and concrete utilising cement, fresh water and river sand were also investigated for comparison purpose. The samples were heated to different target temperatures up to 1000 °C at a heating rate of 5 °C/min, and tested both under hot and cooled conditions. The thermal properties, including temperature gradient, visual observation, mass loss, thermal strain and mechanical properties (i.e. strength, Young's modulus and stress-strain curve) were investigated. X-ray CT scanning and scanning electron microscopy (SEM) were conducted to understand the macro/microscopic changes of the paste and concrete in response to heating. Degradation in mechanical properties of slag paste is attributed mainly to the cracks induced by temperature gradient, pore pressure and phase change. The degradation of concrete is caused by thermal mismatch between paste matrix and aggregates regardless of the use of cement or slag, freshwater or seawater, and river sand or sea sand.
AB - This paper presents an experimental study on the thermal properties of alkali-activated slag paste, mortar and concrete utilising seawater and sea sand exposed to elevated temperature. The thermal properties of paste and concrete utilising cement, fresh water and river sand were also investigated for comparison purpose. The samples were heated to different target temperatures up to 1000 °C at a heating rate of 5 °C/min, and tested both under hot and cooled conditions. The thermal properties, including temperature gradient, visual observation, mass loss, thermal strain and mechanical properties (i.e. strength, Young's modulus and stress-strain curve) were investigated. X-ray CT scanning and scanning electron microscopy (SEM) were conducted to understand the macro/microscopic changes of the paste and concrete in response to heating. Degradation in mechanical properties of slag paste is attributed mainly to the cracks induced by temperature gradient, pore pressure and phase change. The degradation of concrete is caused by thermal mismatch between paste matrix and aggregates regardless of the use of cement or slag, freshwater or seawater, and river sand or sea sand.
KW - Alkali-activated concrete
KW - Elevated temperature
KW - Seawater and sea sand concrete (SWSSC)
KW - Thermal properties
UR - http://www.scopus.com/inward/record.url?scp=85032802770&partnerID=8YFLogxK
U2 - 10.1016/j.conbuildmat.2017.10.104
DO - 10.1016/j.conbuildmat.2017.10.104
M3 - Article
AN - SCOPUS:85032802770
SN - 0950-0618
VL - 159
SP - 704
EP - 724
JO - Construction and Building Materials
JF - Construction and Building Materials
ER -