Reactivity of a tuff-bearing concrete: CL-40 CON-14
Samples of a tuff-bearing concrete have been altered in J-13 groundwater and in the vapor phase over deionized water at 200{degree}C. Crushed and intact discs of the concrete have been studied. The glassy tuff component of the tuff was more extensively reacted than the welded devitrified tuff. The original concrete was formulated to be expansive on curing through the formation of the calcium alumino-sulfate hydrate phase, ettringite. An x-ray diffraction examination of the altered crushed samples shows that the ettringite is no longer present. The original, poorly crystalline calcium-silicate-hydrate has recrystallized to tobermorite. In the rocking autoclave experiments with crushed material, which are the experiments expected to have the fastest reaction rates, the tobermorite has been replaced by a mineral of the gyrolite-truscottite group at the longer reaction times. The disc experiments in J-13 groundwater are characterized by prominent dissolution of the tuff aggregate. Alteration in the vapor phase experiments is primarily in the form of overgrowths on the discs. 10 refs., 27 figs., 12 tabs.
- Research Organization:
- Los Alamos National Lab. (LANL), Los Alamos, NM (United States)
- DOE Contract Number:
- W-7405-ENG-36
- OSTI ID:
- 60694
- Report Number(s):
- LA-11532-MS; ON: DE89010549; TRN: 89:011123
- Resource Relation:
- Other Information: PBD: Apr 1989
- Country of Publication:
- United States
- Language:
- English
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