A platform for research: civil engineering, architecture and urbanism
A platform for research: civil engineering, architecture and urbanism
Effects of heat and pressure on hot-pressed geopolymer
https://orcid.org/0000-0002-1485-3931
https://orcid.org/0000-0001-8566-3863
Highlights Hot-pressed geopolymer requires a low alkali activator content of about 20 wt%. Compressive strength of hot-pressed geopolymer is up to 160 MPa after 30 min curing. Hot-pressing not only reduces the volume of pores but also changes their structures.
Abstract Hot-pressed geopolymers have been introduced as ultra-high early strength ceramic-like materials with an almost pore-less structure. This study investigates the combined effects of pressure and heat on geopolymerization kinetics, microstructure, physical properties, and mechanical performance of geopolymers. The results demonstrate that about 65% of the trapped air is easily removed from the fresh geopolymer matrix using an initial impact pressure. When the pre-compacted matrix is subjected to the hot-pressing, it is further densified in the range of 1–10% as a result of continuous free-water evaporation and compaction. This process not only reduces the size and volume of porosity but also changes the continuous pore network to a closed one. Besides, the increase in hot-pressing promotes higher geopolymer gel formation and accelerates the polycondensation which possesses relatively high mechanical strength up to 160 MPa immediately after the processing. Collectively, these results demonstrate that the hot-pressing technique is a promising processing route for designing geopolymer with a diverse range of mechanical properties in a short and fast manner.
Effects of heat and pressure on hot-pressed geopolymer
https://orcid.org/0000-0002-1485-3931
https://orcid.org/0000-0001-8566-3863
Highlights Hot-pressed geopolymer requires a low alkali activator content of about 20 wt%. Compressive strength of hot-pressed geopolymer is up to 160 MPa after 30 min curing. Hot-pressing not only reduces the volume of pores but also changes their structures.
Abstract Hot-pressed geopolymers have been introduced as ultra-high early strength ceramic-like materials with an almost pore-less structure. This study investigates the combined effects of pressure and heat on geopolymerization kinetics, microstructure, physical properties, and mechanical performance of geopolymers. The results demonstrate that about 65% of the trapped air is easily removed from the fresh geopolymer matrix using an initial impact pressure. When the pre-compacted matrix is subjected to the hot-pressing, it is further densified in the range of 1–10% as a result of continuous free-water evaporation and compaction. This process not only reduces the size and volume of porosity but also changes the continuous pore network to a closed one. Besides, the increase in hot-pressing promotes higher geopolymer gel formation and accelerates the polycondensation which possesses relatively high mechanical strength up to 160 MPa immediately after the processing. Collectively, these results demonstrate that the hot-pressing technique is a promising processing route for designing geopolymer with a diverse range of mechanical properties in a short and fast manner.
Effects of heat and pressure on hot-pressed geopolymer
https://orcid.org/0000-0002-1485-3931
https://orcid.org/0000-0001-8566-3863
Highlights Hot-pressed geopolymer requires a low alkali activator content of about 20 wt%. Compressive strength of hot-pressed geopolymer is up to 160 MPa after 30 min curing. Hot-pressing not only reduces the volume of pores but also changes their structures.
Abstract Hot-pressed geopolymers have been introduced as ultra-high early strength ceramic-like materials with an almost pore-less structure. This study investigates the combined effects of pressure and heat on geopolymerization kinetics, microstructure, physical properties, and mechanical performance of geopolymers. The results demonstrate that about 65% of the trapped air is easily removed from the fresh geopolymer matrix using an initial impact pressure. When the pre-compacted matrix is subjected to the hot-pressing, it is further densified in the range of 1–10% as a result of continuous free-water evaporation and compaction. This process not only reduces the size and volume of porosity but also changes the continuous pore network to a closed one. Besides, the increase in hot-pressing promotes higher geopolymer gel formation and accelerates the polycondensation which possesses relatively high mechanical strength up to 160 MPa immediately after the processing. Collectively, these results demonstrate that the hot-pressing technique is a promising processing route for designing geopolymer with a diverse range of mechanical properties in a short and fast manner.
Effects of heat and pressure on hot-pressed geopolymer
Ranjbar, Navid (author) / Kashefi, Amin (author) / Ye, Guang (author) / Mehrali, Mehdi (author)
2019-09-27
Article (Journal)
Electronic Resource
English
| British Library Online Contents | 2017
| Online Contents | 2017
| Elsevier | 2017
| British Library Online Contents | 2017