MICRO-CT IN STONE RESEARCH AT UGCT
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Tim De Kock (2019)Content of unpublished data is reduced in this PDF.
X-RAY MICRO-CT
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2D imaging of processes
3D Imaging of processes
Water absorption in a limestone(not the same sample left/right)
Dierick et al. 2014, Recent micro-CT scanner developments at UGCT. Nuclear Instruments and Methods in Physics Research Section B: Beam Interactions with Materials and Atoms, 324, 35-40.
Mascchaele et al. 2013. HECTOR: a 240kV micro-CT setup optimized for research, Journal of Physics Conference Series, 463. 4 pp.
SALT CRYSTALLIZATION 3 molal Na2SO4-solution cooled to 0°C : sodium sulfate heptahydrate crystallization Scans taken continuously during 19 minutes at a rate of 1 scan/80 s (pixel size: 24 µm)
Cnudde, V. et al. 2015. Conservation studies of cultural heritage: X-ray imaging of dynamic processes in building materials. EuropeanJournal of Mineralogy, 27 (3), p. 269-278.See also (content removed from this ppt): Derluyn et al. 2015. ICTMS Conf ProceedingsDesarnaud et al. 2015. Journal of Applied Physics
This is a video
FREEZE-THAW CYCLING
scans 00-16 (this is a video)
20 °C
-15°C
Tem
pera
ture
(°C
)
Time (h)
0 h 6 h5 h3 h2 h
start 1st cycle 2nd cycle
Scan 01
Scan 00 Scan 02
Scan 03
Scan 04
Scan 05
8 h
Dynamic CT
14400 projections; 100 ms
800 projections/rotation
Acquisition time 80 s
Time-lapse CT
-20-15-10
-505
101520
0 500 1000 1500 2000 2500 3000 3500 4000
T (
°C)
t (s)
CRYSTALLIZATION & FRACTURE FORMATIONcrystallization at 600 s
t = 560 s t = 800 s
De Kock et al., 2015. A pore-scale study of fracture dynamics in rock using X-ray micro-CT under ambient freeze-thaw cycling. Environmental Science & Technology, 49(5), pp. 2867-2874.
0100200300400500600700800900
1000
0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16
Cra
ck s
ize
(equ
ival
ent d
iam
eter
, µm
)
scan
FREEZE-THAW CYCLING
This is a video
0100200300400500600700800900
1000
0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16
Cac
ksi
ze(e
quiv
alen
t dia
met
er, µ
m)
scan
FREEZE-THAW CYCLING
opening during freezingclosing during thawing
ice crystallization
progressive opening during succesivefrost cycles
fracture propagation
reduction in size differences duringfreezing and thawing
residual strain
stagnation of crack size
accommodation of ice crystallization
2D WATER MIGRATION DURING FREEZING
normalised
This is a video
2D WATER MIGRATION
195 s170 s145 s95 s0 s
GYPSUM CRUST
This is a video
GYPSUM CRUST
PoresGypsum
Dewanckele et al., 2013. Holistic approach of pre-existing flaws on the decay of two limestones. Science of the Total Environment, 447, p. 403-414.
GYPSUM CRUSTinitial 21 days
Dewanckele et al., 2013. Holistic approach of pre-existing flaws on the decay of two limestones. Science of the Total Environment, 447, p. 403-414.
GYPSUM CRUST
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wet dry
Continuous in situ experiments̶ > 100 volumes, 30 min /full rotation, voxel size 5µm̶ Continuous scanning for > 3 days̶ Hard to visualize together, even more challenging to analyze
GYPSUM CRUST 4D representation (unpublished data removed from ppt)
In collaboration with:
De Kock et al., 2019. Continuous time-lapse micro-CT of gypsum crust formation on natural building stone. 4th International conference on Tomography of Materials and Structures (ICTMS), Abstracts.
Tim De Kock ([email protected]; [email protected])
Thank You