Abstract
The effect of salt concentration on swelling pressure (dPext) of water-saturated bentonite was calculated based on the thermodynamic data of water at montmorillonite surface and of water in solutions of various salinities coming in contact with the montmorillonite. Activities (aw) of water at montmorillonite surface were obtained as a function of water content and temperature by a vapor pressure method, and the relative partial molar Gibbs free energies (dGw) of the water were determined. Water affected from the montmorillonite surface was estimated to be almost all interlayer water. dPext versus montmorillonite partial density was estimated for solutions of various salinities and compared to data measured for various montmorillonite contents and silica sand contents. The calculated dP ext decreased with increasing salinity. The effect of salinity on dPext was not clear in the measured data due to the scattering in the measured data. This cause is presumed to be due to the increase of the ionic strength of porewater by dissolution of soluble minerals.
| Original language | English |
|---|---|
| Pages (from-to) | 307-312 |
| Number of pages | 6 |
| Journal | Materials Research Society Symposium Proceedings |
| Volume | 1124 |
| Publication status | Published - 2009 |
| Externally published | Yes |
| Event | 2008 MRS Fall Meeting - Boston, MA, United States Duration: Dec 2 2008 → Dec 4 2008 |
ASJC Scopus subject areas
- Materials Science(all)
- Condensed Matter Physics
- Mechanics of Materials
- Mechanical Engineering