Abstract
Cylindrical samples of 11-13. wt% aqueous bentonite dispersions with a range of resting times after preparation (0-72. h) were subject to axial squeezing and revealed a transition from a Bingham liquid-like behavior to solid-like behavior. The liquid-like behavior is characterized by viscous spreading arrested by the yield stress, whereas the solid-like behavior is characterized by stasis at lower loads followed by discontinuity of the displacement and cracking above some critical level of load. A mechanical response, dependent on resting time, implied irreversible aging as a result of slow swelling of the clay crystallites, i.e. the internal structure being built over time in the material at rest. Dispersions of 11. wt% and 12. wt% transitioned from liquid-like to solid-like behavior in a single experiment at a resting time of 24. h and 3. h, respectively. At higher concentrations (18-22. wt%) the material always behaves as a solid. The solid-like behavior is distinguished from the liquid-like behavior by the appearance of cracks. The additional bending and buckling experiments conducted with dispersions of 18-22. wt% revealed Young's moduli of 330-500. kPa, yield stresses of 9-15. kPa, cracking stresses of 15-25. kPa, and cracking strains of 8-10%. For all concentrations explored, a linear dependence of the yield stress on concentration was found. It is demonstrated for the first time using uniaxial compression that liquid bentonite dispersions at a concentration of 11-12. wt% reveal transition to a solid in a single experiment where they become capable of developing surfaces of discontinuity of the displacement.
| Original language | English |
|---|---|
| Pages (from-to) | 50-64 |
| Number of pages | 15 |
| Journal | Journal of Non-Newtonian Fluid Mechanics |
| Volume | 219 |
| DOIs | |
| Publication status | Published - 2015 May 1 |
Fingerprint
Keywords
- Bending
- Bentonite
- Buckling
- Compression
- Cracking
- Yield stress
ASJC Scopus subject areas
- Chemical Engineering(all)
- Materials Science(all)
- Condensed Matter Physics
- Mechanical Engineering
- Applied Mathematics
Cite this
Bentonite dispersions : Transition from liquid-like to solid-like behavior and cracking. / Pelot, D. D.; Jun, S.; Yarin, Alexander.
In: Journal of Non-Newtonian Fluid Mechanics, Vol. 219, 01.05.2015, p. 50-64.Research output: Contribution to journal › Article
}
TY - JOUR
T1 - Bentonite dispersions
T2 - Transition from liquid-like to solid-like behavior and cracking
AU - Pelot, D. D.
AU - Jun, S.
AU - Yarin, Alexander
PY - 2015/5/1
Y1 - 2015/5/1
N2 - Cylindrical samples of 11-13. wt% aqueous bentonite dispersions with a range of resting times after preparation (0-72. h) were subject to axial squeezing and revealed a transition from a Bingham liquid-like behavior to solid-like behavior. The liquid-like behavior is characterized by viscous spreading arrested by the yield stress, whereas the solid-like behavior is characterized by stasis at lower loads followed by discontinuity of the displacement and cracking above some critical level of load. A mechanical response, dependent on resting time, implied irreversible aging as a result of slow swelling of the clay crystallites, i.e. the internal structure being built over time in the material at rest. Dispersions of 11. wt% and 12. wt% transitioned from liquid-like to solid-like behavior in a single experiment at a resting time of 24. h and 3. h, respectively. At higher concentrations (18-22. wt%) the material always behaves as a solid. The solid-like behavior is distinguished from the liquid-like behavior by the appearance of cracks. The additional bending and buckling experiments conducted with dispersions of 18-22. wt% revealed Young's moduli of 330-500. kPa, yield stresses of 9-15. kPa, cracking stresses of 15-25. kPa, and cracking strains of 8-10%. For all concentrations explored, a linear dependence of the yield stress on concentration was found. It is demonstrated for the first time using uniaxial compression that liquid bentonite dispersions at a concentration of 11-12. wt% reveal transition to a solid in a single experiment where they become capable of developing surfaces of discontinuity of the displacement.
AB - Cylindrical samples of 11-13. wt% aqueous bentonite dispersions with a range of resting times after preparation (0-72. h) were subject to axial squeezing and revealed a transition from a Bingham liquid-like behavior to solid-like behavior. The liquid-like behavior is characterized by viscous spreading arrested by the yield stress, whereas the solid-like behavior is characterized by stasis at lower loads followed by discontinuity of the displacement and cracking above some critical level of load. A mechanical response, dependent on resting time, implied irreversible aging as a result of slow swelling of the clay crystallites, i.e. the internal structure being built over time in the material at rest. Dispersions of 11. wt% and 12. wt% transitioned from liquid-like to solid-like behavior in a single experiment at a resting time of 24. h and 3. h, respectively. At higher concentrations (18-22. wt%) the material always behaves as a solid. The solid-like behavior is distinguished from the liquid-like behavior by the appearance of cracks. The additional bending and buckling experiments conducted with dispersions of 18-22. wt% revealed Young's moduli of 330-500. kPa, yield stresses of 9-15. kPa, cracking stresses of 15-25. kPa, and cracking strains of 8-10%. For all concentrations explored, a linear dependence of the yield stress on concentration was found. It is demonstrated for the first time using uniaxial compression that liquid bentonite dispersions at a concentration of 11-12. wt% reveal transition to a solid in a single experiment where they become capable of developing surfaces of discontinuity of the displacement.
KW - Bending
KW - Bentonite
KW - Buckling
KW - Compression
KW - Cracking
KW - Yield stress
UR - http://www.scopus.com/inward/record.url?scp=84961291566&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=84961291566&partnerID=8YFLogxK
U2 - 10.1016/j.jnnfm.2015.03.001
DO - 10.1016/j.jnnfm.2015.03.001
M3 - Article
VL - 219
SP - 50
EP - 64
JO - Journal of Non-Newtonian Fluid Mechanics
JF - Journal of Non-Newtonian Fluid Mechanics
SN - 0377-0257
ER -