MODELLING INTERNAL CURING IN CONCRETE Mateusz Wyrzykowski Pietro Lura Dariusz Gawin W(H)YDOC 12, ParisTech, 22.11.2012 Concrete & Construction Chemistry
MODELLING INTERNAL CURING IN CONCRETE
Mateusz WyrzykowskiPietro Lura
Dariusz Gawin
W(H)YDOC 12, ParisTech, 22.11.2012
Concrete & Construction Chemistry
Materials Sci ence & Technolog y2
PhD Thesis 2005-2010
Dariusz Gawin- Department of Building Physics and Building
MaterialsLodz University of Technology, Poland
Pietro Lura- Empa, Swiss Federal Laboratories for
Materials Science and TechnologyConcrete/Construction Chemistry Lab
- Intitute for Building Materials, ETH Zurich, Switzerland
Materials Sci ence & Technolog y3
Outline
Motivation Autogenous shrinkage
Modeling of phenomena at early age
Internal curing Modelling internal curing at meso-level Modelling internal curing at macro-level
Further applications and developments of the model Summary
Materials Sci ence & Technolog y4
Motivation
Shrinkage and cracking problem
Measuring techniqueMechanism
Solution
capp
r
RH<100%
cappcapp
r
RH<100%
•ASTM C1698-09•Loser, Münch, Lura, CCR (2010)•Lura, Jensen, van Breugel CCR (2003)•Jensen & Hansen CCR (2001, 2002)
SAP
Materials Sci ence & Technolog y5
MotivationInternal curing with superabsorbent polymers (SAP)
•Jensen & Hansen CCR (2001, 2002)dry
swollen
-400
-300
-200
-100
0
0 2 4 6 8 10 12 14 16Time [days]
Auto
geno
us s
train
[ m
/m]
plain-exp.
w ith SAP-exp.
Materials Sci ence & Technolog y6
Availability of water
KineticJensen & Lura MS 2006
Thermodynamic
Motivation
Materials Sci ence & Technolog y7
Water transport from the SAP
Optimization of the chemistry and particle size distribution of the SAP:
When is the water released from the SAP?
How far does water reach in the hardening cement paste?
How small should the SAP be? Lura et al. 2004
Motivation
Materials Sci ence & Technolog y8
Outline
Motivation Autogenous shrinkage
Modeling of phenomena at early age
Internal curing Modelling internal curing at meso-level Modelling internal curing at macro-level
Further applications and developments of the model Summary
Materials Sci ence & Technolog y9
Lura, Jensen, van Breugel, CCR (2003) Lura & Jensen, (2005, 2007)
Autogenous shrinkage
Self-desiccation
Autogenous shrinkage
Chemical shrinkage
capp
r
RH<100%
cappcapp
r
RH<100%
Materials Sci ence & Technolog y10
Autogenous phenomena-experimetnal methods
Balance
Paraffin oilWater
Sample
Linear measurementVolumetric measurement
Internal RHAutogenous deformation
Water activity (Rotronic)
Materials Sci ence & Technolog y11
Outline
Motivation Autogenous shrinkage
Modeling of phenomena at early age
Internal curing Modelling internal curing at meso-level Modelling internal curing at macro-level
Further applications and developments of the model Summary
Materials Sci ence & Technolog y12
Description of phenomena in fresh cement-based materialsMathematical model – fundamental assumptions
Multi-phase porous medium solid (skeleton), water (capillary water + bound water), gaseous phase (dry air + water vapour).
Various mechanisms of mass and energy transport
Full coupling: hygral, thermal, chemical, mechanical phenomena
• Gawin, Pesavento, Schrefler, IJNME (2006)
Materials Sci ence & Technolog y13
Description of phenomena… Mathematical model
Macroscopic governing equations
The dry air + skeleton mass conservation
The water species + skeleton mass conservation
The multiphase medium enthalpy balance
The multiphase medium momentum balance (mechanical equilibrium)
Evolution equation for hydration
• Gawin, Pesavento, Schrefler, IJNME (2006)
Materials Sci ence & Technolog y14
Description of phenomena… Mathematical model
State variables gas pressure, pg
capillary pressure, pc
temperature, T displacement vector, u
Evolution variable hydration degree, hydr
Materials Sci ence & Technolog y15
Description of phenomena… Mathematical model
Hydration evolution(Ulm & Coussy, 1996)
Water species conservation equation
Scheme of the early-age processes description (hygral and mechanical phenomena)
nhydrhydr wtt
m
Drop of saturation,Increase of capillary pressure
Mechanical equilibrium equation
Effective stress principle
Increase of effective stress
Materials Sci ence & Technolog y16
Description of phenomena… Numerical model
Description of the material behavior at different scale levels
Meso-level (~mm) Macro level (~cm-m)
Materials Sci ence & Technolog y17
Outline
Motivation Autogenous shrinkage
Modeling of phenomena at early age
Internal curing Modelling internal curing at meso-level Modelling internal curing at macro-level
Further applications and developments of the model Summary
Materials Sci ence & Technolog y18
Outline
Motivation Autogenous shrinkage
Modeling of phenomena at early age
Internal curing Modelling internal curing at meso-level Modelling internal curing at macro-level
Further applications and developments of the model Summary
Materials Sci ence & Technolog y19
Modelling internal curing at the meso-level
Meso level simulations
Cement paste w/c 0.25, 6% of entrained water (vol.)
Trtik, Münch, Weiss, Herth, Kaestner, Lehmann, Lura, Neutron tomography investigation of water release … 2010
0
20
40
60
80
100
120
0 4 8 12 16 20 24Time (hours)
Cum
ulat
ive
sign
al (%
)
Portland cement paste w/c 0.25, curing 28C
When is the water released from the SAP?
How far does water reach in the hardening cement paste?
Materials Sci ence & Technolog y20
Water and solid skeleton mass conservation
Modelling internal curing at the meso-level Mathematical model
hydrhydrws
w
hydrws
gwcg
w
rww
gg
rggw
g
gwgwd
g
wagw
ww
gw
gw
www
wswgw
s
c
cwgww
mmSmSpgradpgradkkdiv
pgradkkdivppgrad
MMMdiv
tdivSS
tT
TnS
tTSnnSn
tp
pSn
1
1
1111
2
I
IDu
Accumulation terms
Flux terms Source terms
Materials Sci ence & Technolog y21
Modelling internal curing at the meso-level
Simulations at the meso-level characteristics of the components of REV
Permeability evolution in the paste
1.0E-24
1.0E-22
1.0E-20
1.0E-18
1.0E-16
1.0E-14
0.0 0.2 0.4 0.6 0.8 1.0Hydration degree [-]
Intri
nsic
per
mea
bilit
y [m
2 ]
w /c 0.25-sim.
w /c 0.25-GEM model
cgw
rwws
w gradp+gradpμkkvnS
Materials Sci ence & Technolog y22
Modelling internal curing at the meso-level
Results from the meso-level
Cement paste w/c 0.25, 6% of entrained water (vol.)
Wyrzykowski, Lura, Pesavento, Gawin, Modeling of water migration ... MTENG (2012)
Materials Sci ence & Technolog y23
70
80
90
100
0 1 2 3 4 5 6 7 8 9 10 11 12 13 14Time [days]
Satu
ratio
n [%
]
Modelling internal curing at the meso-level
Saturation evolution in time-cement paste
at the reservoir2.5 mm distance
SAP size 2.4 mm, w/ce 0.035, max dist. 2.5 mm
SAP size 2.4 mm, w/ce 0.050, max dist. 2.2 mm
Wyrzykowski, Lura, Pesavento, Gawin, Modeling of water migration ... MTENG (2012)
Materials Sci ence & Technolog y24
Modelling internal curing at the meso-level
Saturation evolution in time-cement paste
SAP size 2.4 mm, w/ce 0.050, max dist. 2.2 mm
0.E+00
5.E-05
1.E-04
0 1 2 3 4 5 6 7 8 9 10 11 12 13 14Time [h]
Rate
of a
dditi
onal
wat
er re
ceiv
ed
[% o
f sat
/s]
Wyrzykowski, Lura, Pesavento, Gawin, Modeling of water migration ... MTENG (2012)
Materials Sci ence & Technolog y25
Conclusion
70
80
90
100
0 1 2 3 4 5 6 7 8 9 10 11 12 13 14
Time [days]
Satu
ratio
n [%
]
SAP size 800 m, w/ce 0.050, max dist. 740 m
SAP size 2.4 mm, w/ce 0.050, max dist. 2.2 mm
For the commonly applied sizes of SAP the whole volume of cured material is practically uniformly and instantaneously provided with curing water during the initial days of hydration
Wyrzykowski, Lura, Pesavento, Gawin, Modeling of water migration ... MTENG (2012)
Materials Sci ence & Technolog y26
Outline
Motivation Autogenous shrinkage
Modeling of phenomena at early age
Internal curing Modelling internal curing at meso-level Modelling internal curing at macro-level
Further applications and developments of the model Summary
Materials Sci ence & Technolog y27
Modelling internal curing at the macro-level
Additional water source term
IChydrhydrws
w
hydrws
gwc
cwgww mmmSmS
tp
pS
n
1
tp
pS
pmc
c
ICwwc
IC
1
Capillary suction
Demand-supply w
hydrhydrhydrs
w
m
-11 0
0
20
40
60
80
100
0 2 4 6 8 10 12 14 16
Time [days]
Satu
ratio
n [%
] capillary suction'demand-supply'
Wyrzykowski, Lura, Pesavento, Gawin, Modeling of internal curing in maturing mortar, CCR (2011)
Materials Sci ence & Technolog y28
Modelling internal curing at the macro-level
Simulation results – w/c 0.3 mortar with SAP
Mortarsw/c 0.3 + 0.04
00.10.2
0.30.40.50.60.7
0.80.9
1
0 1 2 3 4 5 6
Time [days]
Nor
m. h
ydra
tion
degr
ee [-
]
plain-exp.plain-sim.with SAP-exp.with SAP-sim.
80
82
84
86
88
90
92
94
96
98
100
0 2 4 6 8 10 12 14 16Time [days]
RH [%
]
plain-exp.plain-sim.w ith SAP-exp.w ith SAP-sim. cap. suctionw ith SAP-sim. 'demand-supply'
Wyrzykowski, Lura, Pesavento, Gawin, Modeling of internal curing in maturing mortar, CCR (2011)
Materials Sci ence & Technolog y29
Modelling internal curing at the macro-level
Simulation results – w/c 0.3 mortar with SAP
Mortarsw/c 0.3 + 0.04
-400
-300
-200
-100
0
0 2 4 6 8 10 12 14 16Time [days]
Auto
geno
us s
train
[ m
/m]
plain-exp.plain-sim.w ith SAP-exp.w ith SAP-sim. cap. suctionw ith SAP-sim. 'demand-supply'
Wyrzykowski, Lura, Pesavento, Gawin, Modeling of internal curing in maturing mortar, CCR (2011)
Materials Sci ence & Technolog y30
Conclusions
At the meso-level the transport of water is explicitly analyzed the whole volume of material is practically uniformly and
instantaneously provided with curing water during the first day of hydration
At the macro-level the additional source term is introduced internal curing may be also analyzed directly at the macro-level two source terms describing internal curing are proposed , i.e.
capillary suction mechanism and demand-supply mechanism
Materials Sci ence & Technolog y31
Outline
Motivation Autogenous shrinkage
Modeling of phenomena at early age
Internal curing Modelling internal curing at meso-level Modelling internal curing at macro-level
Further applications and developments of the model Summary
Materials Sci ence & Technolog y32
Outline
Motivation Autogenous shrinkage
Modeling of phenomena at early age
Internal curing Modelling internal curing at meso-level Modelling internal curing at macro-level
Further applications and developments of the model Summary
Materials Sci ence & Technolog y33
Further applications
Autogenous conditions vs. realistic conditions
Drying
Self-heating + cooling
External load
Autogenous phenomena
Materials Sci ence & Technolog y34
Further applicationsDrying shrinkage
Gawin, Pesavento, Schrefler, IJNME (2006)Gawin, Wyrzykowski, Pesavento, J. Build Phys. (2008)
Photo: PCA
Development of capillary pressure
Increase of effective stress
Shrinkage (+creep) strains
hydrhydrws
w
hydrws
gwcg
w
rww
gg
rggw
g
gwgwd
g
wagw
ww
gw
gw
www
wswgw
s
c
cwgww
mmSmSpgradpgradkkdiv
pgradkkdivppgrad
MMMdiv
tdivSS
tT
TnS
tTSnnSn
tp
pSn
1
1
1111
2
I
IDu
Materials Sci ence & Technolog y35
Further applicationsSelf-heating / cooling
Gawin, Pesavento, Schrefler, IJNME (2006)
Heat of hydration
Thermal strains
Heat transfer temperature gradients 05101520253035404550
0 5 10 15 20 25 30 35
Tempe
rature [°C]
Time [days]
E3 193cm mid‐height
simulation
Materials Sci ence & Technolog y36
Further applications
diffusion
water
0
2
4
6
8
10
12
14
16
0 2 4 6 8 10 12 14 16 18 20 22
Ca ions concentr. [mol/m3]
Solid
Ca
conc
entr
. [km
ol/m
3 ]
0.00E+00
5.00E-07
1.00E-06
1.50E-06
2.00E-06
2.50E-06
3.00E-06
Sour
ce [m
ol/m
3 s]
SCa-Ca,T=25°CSCa-Ca,T=60°Csource,T= 25°Csource,T= 60 C
Calcium leaching
Gawin, Pesavento, Schrefler, Int. J. Solids Struct. (2008)Koniorczyk & Gawin, J. Build. Phys., (2006)
Salts in concrete
Materials Sci ence & Technolog y37
Further applications
Alkali-Silica Reaction (ASR)
Gawin, Pesavento, Schrefler, Comput. Methods Appl. Mech. Engrg.(2003)Pesavento, Gawin, Wyrzykowski, Schrefler, Simoni, Comput. Methods Appl. Mech. Engrg.(accepted)
Concrete at high temperatures
Materials Sci ence & Technolog y38
Outline
Motivation Autogenous shrinkage Description of phenomena in fresh concrete Application of the model for internal curing:
Modelling internal curing at meso-level Modelling internal curing at macro-level
Further applications and developments Summary
Materials Sci ence & Technolog y39
Summary
Porous media mechanics allows for macroscopic analysis of phenomena in maturing concrete as the direct effect of their physical origins (mechanistic approach)
The model can be considered as a general framework for description of concrete at the macro level incorporation of sub-models possible
Further applications of the model: maturing in realistic conditions (self-heating, shrinkage + creep) calcium leaching salts in concrete concrete at high temperature ASR