Chemical evolution of cementitious materials with high proportion of fly ash and slag
- Westinghouse Hanford Co., Richland, WA (United States)
- Illinois Univ., Urbana, IL (United States)
Cement mixtures containing high proportions of slag and fly ash were tested to assess their suitability to immobilize simulated off-gas waste solutions after vitrification of low-level radioactive tank wastes stored at Hanford. Materials were mixed with carbonated or alkaline solutions and cured initially adiabatically, then at 70{degrees}C. Chemical changes were monitored for 7 months using X-ray diffraction, selective dissolution and SEM; NMR was utilized to follow the polymerization of silicate species. The process of hydration during the first months of curing was characterized by formation of quite crystalline Al-substituted C-S-H structurally related to 1.1 nm tobermorite and traces of zeolites in some materials. A low content of calcium hydroxide was found in all materials after I month of curing. The SEM examination demonstrated rapidly decreasing porosity, making the mixtures favorable for long-term durability.
- Research Organization:
- Westinghouse Hanford Co., Richland, WA (United States)
- Sponsoring Organization:
- USDOE, Washington, DC (United States)
- DOE Contract Number:
- AC06-87RL10930
- OSTI ID:
- 224960
- Report Number(s):
- WHC-SA-3022; CONF-951155-113; ON: DE96009105
- Resource Relation:
- Conference: Fall meeting of the Materials Research Society (MRS), Boston, MA (United States), 27 Nov - 1 Dec 1995; Other Information: PBD: Dec 1995
- Country of Publication:
- United States
- Language:
- English
Similar Records
Self-degradable Slag/Class F Fly Ash-Blend Cements
Geopolymeric materials prepared using Class F fly ash and elevated temperature curing