Research on the pretreatment and mechanical performance of undisturbed phosphogypsum
| Autor: | Ailian Zhang, Qian Wang, Bin Yao, Yan Han, Liyu Feng, Linchun Zhang, Ke Li, Xiaojian Gao |
|---|---|
| Rok vydání: | 2020 |
| Předmět: |
Materials science
Silica fume Materials Science (miscellaneous) 0211 other engineering and technologies 020101 civil engineering 02 engineering and technology 0201 civil engineering law.invention Flexural strength law 021105 building & construction lcsh:TA401-492 medicine Ageing time Dehydration Composite material Compressive and flexural strength Cement Differential thermal analysis medicine.disease Portland cement Compressive strength Ground granulated blast-furnace slag Fly ash Alkali activator lcsh:Materials of engineering and construction. Mechanics of materials Phosphogypsum |
| Zdroj: | Case Studies in Construction Materials, Vol 13, Iss, Pp e00400-(2020) |
| ISSN: | 2214-5095 |
| Popis: | In this study, dehydration process of original phosphogypsum (PG) was firstly studied by differential thermal analysis method, and the optimal heat treatment temperature was obtained. Subsequently, the effects of dehydration time and ageing time on compressive and flexural strengths of PG pastes were studied. Additionally, the influence of blast furnace slag, silica fume and Portland cement on compressive strength of PG were determined. Results showed that CaSO4·2H2O in PG were dehydrated at three steps and the related dehydration temperatures were 80 ℃, 140 ℃ and 160 ℃. When the dehydration duration at 140 ℃ was 9 h and the ageing time was 5 d the PG paste obtained the best flexural and compressive strength. The addition of blast furnace slag and cement behaved a positive effect on the mechanical strength of PG. The 28 d compressive strength of PG mixture was increased by 97.8 % when the dosage of cement was 40 % by the mass ratio of total binder. Unfortunately, fly ash led to the decreasing mechanical strengths of PG mixture. |
| Databáze: | OpenAIRE |
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