TY - JOUR
T1 - Influence of spatial dislocation of water on the properties of lightweight high-performance concrete
AU - Lu, Jian Xin
AU - Shen, Peiliang
AU - Li, Long
AU - Asad Ali, Hafiz
AU - Jiang, Yi
AU - Sun Poon, Chi
N1 - Funding Information:
The current work was supported by the Hong Kong Innovation and Technology Fund (ZM3H) and the General Research Fund from the Hong Kong Research Grants Council. The first author wishes to thank the financial support from the Teaching Postgraduate Studentship Scheme. The authors would also like to express appreciation to D. P. Bentz (National Institute of Standards and Technology) for helpful discussion regarding the results of hydration kinetic. The technical assistance of Dorothy Chan (Department of Civil and Environmental Engineering) in performing the SEM & BSE experiment is gratefully acknowledged.
Publisher Copyright:
© 2023 Elsevier Ltd
PY - 2023/2/27
Y1 - 2023/2/27
N2 - To prepare high-performance concrete, the mixing water was normally blended with the dry constituents directly, whereas in this study part of water was pre-located in the lightweight aggregates (LWA) for producing a high-performance lightweight concrete (HPLC). With the pre-location of water in the LWA, an extremely low w/b ratio paste (ultra high-performance composite) was resulted for producing HPLC. High-performance cement mortar (HPCM) was prepared with similar volumes of natural aggregates for comparison. Based on the initial spatial dislocation of mixing water in two systems, the physical, thermal and durability properties of high-performance cementitious composites were evaluated and compared. The results showed that the HPLC experienced delayed heat evolution when compared with that of the HPCM, while the cumulative heat output and degree of cement hydration of the two systems were similar. With the use of an increasing amount of LWA, the density of HPLC decreased significantly while the water penetration and ion permeability of HPLC were comparable to those of HPCM. More importantly, the HPLC exhibited a higher structural efficiency and much lower thermal conductivity than the HPCM. In addition to the pozzolanic reactivity and internal curing provided by the water-entrained LWA, the dislocation of mixing water method also enhanced the microhardness of the paste matrix, which contributed to the excellent performance of HPLC.
AB - To prepare high-performance concrete, the mixing water was normally blended with the dry constituents directly, whereas in this study part of water was pre-located in the lightweight aggregates (LWA) for producing a high-performance lightweight concrete (HPLC). With the pre-location of water in the LWA, an extremely low w/b ratio paste (ultra high-performance composite) was resulted for producing HPLC. High-performance cement mortar (HPCM) was prepared with similar volumes of natural aggregates for comparison. Based on the initial spatial dislocation of mixing water in two systems, the physical, thermal and durability properties of high-performance cementitious composites were evaluated and compared. The results showed that the HPLC experienced delayed heat evolution when compared with that of the HPCM, while the cumulative heat output and degree of cement hydration of the two systems were similar. With the use of an increasing amount of LWA, the density of HPLC decreased significantly while the water penetration and ion permeability of HPLC were comparable to those of HPCM. More importantly, the HPLC exhibited a higher structural efficiency and much lower thermal conductivity than the HPCM. In addition to the pozzolanic reactivity and internal curing provided by the water-entrained LWA, the dislocation of mixing water method also enhanced the microhardness of the paste matrix, which contributed to the excellent performance of HPLC.
KW - High-performance concrete
KW - Permeability
KW - Structural efficiency
KW - Thermal insulation
KW - UHPC
UR - http://www.scopus.com/inward/record.url?scp=85146052251&partnerID=8YFLogxK
U2 - 10.1016/j.conbuildmat.2023.130322
DO - 10.1016/j.conbuildmat.2023.130322
M3 - Journal article
AN - SCOPUS:85146052251
SN - 0950-0618
VL - 367
JO - Construction and Building Materials
JF - Construction and Building Materials
M1 - 130322
ER -