© LNEC 2012 © LNEC 2012
Research Perspectives in Embankment Dams at LNEC
Laura Caldeira [email protected]
Head of the Geotechnique Department
Dam World Conference 8-11th October 2012 Maceio, Brazil
© LNEC 2012
Summary
>The influence of upstream zones in the limitation of the progression of internal erosion in zoned dams
>Self-hardening slurry walls design and quality control
2
© LNEC 2012
Earthquake
2%
Slope
instability
4%
Internal
erosion
48%
Overtopping
46%
Importance of internal erosion to dam safety
Source: Foster, Fell e Spannagle (2000)
Overall statistics of embankment dams failures
3
© LNEC 2012
Internal erosion process leading to failure
Section A-A'
Concentrated leakagethrough a transverse crack
Section A-A'
Longitudinal view
INITIATION
CONTINUATION OR FILTRATION
PROGRESSION
BREACH FORMATION
A
A'
Absence ormalfunctioning ofdownstream filter
Enlargment of theconcentrated leak
(erodability of soil)
Reservoirempties afterpipe collapse
Cross Sectional view
Breach formationB
B'
Section A-A'
Pipeformation
Flowincreases
Cracks above pipe
e.g. cracking mechanismby arching effect
Section B-B'
Does the upstream zone: - Limits the eroding flow? - fills in the flaw in the core?
4
© LNEC 2012
Section A-A'
Concentrated leakagethrough a transverse crack
Section A-A'
Longitudinal view
INITIATION
CONTINUATION OR FILTRATION
PROGRESSION
BREACH FORMATION
A
A'
Absence ormalfunctioning ofdownstream filter
Enlargment of theconcentrated leak
(erodability of soil)
Reservoirempties afterpipe collapse
Cross Sectional view
Breach formationB
B'
Section A-A'
Pipeformation
Flowincreases
Cracks above pipe
e.g. cracking mechanismby arching effect
Section B-B'
Does the upstream zone: - Limits the eroding flow? - fills in the flaw in the core?
Internal erosion process leading to failure (cont)
5
© LNEC 2012
Tunbridge Dam, Tasmânia, Australia, 11/28/2008
Source: Jeffery Farrar (2008)
Progression of internal erosion to piping
6
© LNEC 2012
Source: Hanson e Hunt (USDA, 2007)
Progression of internal erosion to piping
7
© LNEC 2012
Erodability of soils in concentrated leaks > Hole Erosion Test (HET)
Specimen in standardProctor mould
Downstream chamber
of acrylic glass
Upstream chamber
of acrylic glassDrilled hole
Ø6 mm
l/h
Flowmeter
Control valve
Upstream tank suppliedby large reservoir above
Downstream tank
Purge Purge
Pea gravel20 mm to 30 mm
Scale
Upstream
piezometer
Downstream
piezometer
300 mm to 1100 mm
˜ 200 mm
Drain
Drain
8
© LNEC 2012
Hole Erosion Test (HET) during test
9
© LNEC 2012
Hole Erosion Test
> Axial hole at the end of a test
10
© LNEC 2012
Limitation of progression of piping
>Flow restriction action
Influence of the presence of upstream zones
Flow Limitation Erosion Test (FLET) Crack-Filling Erosion Test (CFET)
>Crack-filling action
Upstream material Core Filter
Upstream material Core 11
© LNEC 2012
Test cell developed at LNEC for FLET and CFET
12
© LNEC 2012
Flow Limitation Erosion Test (FLET)
Acylic glass
cover
l/h
Electromagnetic
flow meter
Upstream
control valve
Eroding fluid from
storage tank above
Downstream tank
Upstream tank
1250 mm to 2250 mm
200 mm
To drain
To drain
Downstream
control valve
Core material Upstream material
U/S
piezometer
INT
piezometer
D/S
piezometer
Valve Valve
Scale
(mm)
Two
concentric
springs
Digital
cameraOutlet chamber
Pre-formed
pipe (Di)
2300
2200
2100
2000
1900
1800
400
300
200
100
50
Inlet chamber
13
© LNEC 2012
Flow Limitation Erosion Test
> Steps for assembly of test cell and specimen preparation
Step 1 Step 5Step 4Step 3
Upstream
material
90º
Step 2
Core
14
© LNEC 2012
Upstream materials tested in the FLET
Grain Size (mm)
Perc
ent
pa
ssin
gb
yw
eig
ht
(%)
0.001 0.01 0.02 0.05 0.1 0.2 0.5 1 2 3 4 5 7 10 20 30 50
2"3/4"3/8"#4#10#20#40#100#200
ASTM Sieve SizesHydrometer Analysis
Silt or ClayGravelSand
CoarseFineCMediumFine
0
20
40
60
80
100
Core
5% limit
15% limit
30% limit
Upstream materials
with non-plastic fines
with plastic fines
Gap-graded
15
© LNEC 2012 Time (minutes)
Flo
wR
ate
(lit
ers/
h)
Pie
zo
me
tric
le
vel
(cm
)
0 5 10 15 201000 0
1200 50
1400 100
1600 150
1800 200
2000 250Flow rateU/S piezINT piezD/S piez
Df =
20 mmDf = 48 mm
CO RE UPSTREAMZONE
Some results of carried out FLET’s at LNEC > Progression of erosion without flow restriction
16
© LNEC 2012
Some results of carried out FLET’s at LNEC > Flow restriction due to non-erodible upstream material
Time (minutes)
Flo
wra
te(l
iters/
h)
Pie
zo
me
tric
le
vel
(cm
)
0 10 20 30 40 50 60 70 801100 0
1200 80
1300 160
1400 240
1500 320
1600 400
Flow rate stabilizesand effluent clears
Flow rateU/S piezINT piezD/S piez
COREUPSTREAM
Z ONE
FLET B1-02
Df =26 m m
Df = 12 m m
17
© LNEC 2012 Time (minutes)
Flo
wra
te(l
iters/
h)
Pie
zo
me
tric
le
ve
l(c
m)
0 20 40 60 80 100 120 1400 0
400 80
800 160
1200 240
1600 320
2000 400
Onset of pipe
Water bleedRe-open valve
Close valve
Clogged pipe
Flow rateU/S piezINT piezD/S piez
FLET E1-01a
D f =
14 mm
CORE UPSTREAMZONE
blockage
Some results of carried out FLET’s at LNEC > Flow rate stops completely (self-healing ability)
Core specimen Upstream specimen
Detail of the axial hole of specimens after test 18
© LNEC 2012
Some results of carried out FLET’s at LNEC > Erosion process slows down during a period
Time (minutes)
Flo
wrate
(lit
ers/
h)
Pie
zo
me
tric
le
vel
(cm
)
0 10 20 30 40 50 600 0
400 100
800 200
1200 300
1600 400
2000 500
"Blowout" of gravel part.
Flow rateU/S piezINT piezD/S piez
Df =
27 mmDf = 36 mm
COREUPSTREAM
ZONE
19
© LNEC 2012
> The performed tests showed that the FLET allows the evaluation of the flow restriction action by an upstream material, that is, if the piping process in the core stops, slows down or progresses.
> The flow restriction action is strongly influenced by some characteristics of the upstream materials, including the fines and gravel contents, as well as the plastic nature of the fines.
> The compaction water content of the upstream material affects strongly the progression of piping erosion.
> The non-plastic fines of soils compacted to the dry side tends to erode more rapidly, leaving unbounded the gravel particles with potential to initiate a self-healing mechanism at the interface or inside the core sample.
Major outcomes of carried out FLET’s
20
© LNEC 2012
Material de
montante
Filling in with eroded particles
from the upstream material
Filter does not retains the
particles from the core
Material settles
Clayey core
Filter retains the coarser particles
eroded from the upstream material
Sinkhole
RockfillRockfill
Crack-Filling Erosion Test (CFET)
> Conceptual model of Crack-filling action mechanism
21
© LNEC 2012
WAC Bennett Dam | Canadá Embankment height=186 m | Length= 2 km Electricity production= 13 biliões kWh/ano
Source: Steve Garner, BCHydro (2007)
Crack-Filling Erosion Test (CFET)
> Example of sinkhole formation at the embankment crest
22
© LNEC 2012
Crack-Filling Erosion Test (CFET)
> Placement of the filter layer > CFET setup ready to test
23
© LNEC 2012
> Crack-filling of the axial hole on the core with an uniform fine sand
Crack-Filling Erosion Test (CFET)
24
© LNEC 2012
Crack-Filling Erosion Test (CFET)
> Crack-filling of the axial hole on the core with an uniform fine sand
25
© LNEC 2012
> The preliminary tests showed that the CFET is suitable for the evaluation of the crack-filling action by granular upstream materials.
> The filter layer has an important role in the crack filling action, by retaining some of the particles that are washed in from the upstream material.
> The potential benefits of crack filling action arise from the compatibility between the particle sizes of the upstream material and those of the downstream filter.
> Tests are currently underway examining the crack-filling action due to the presence of several types of coarse grained upstream materials (obtained by blending some fines, and sand and gravel particles).
Major outcomes of preliminary CFET’s
26
© LNEC 2012 © LNEC 2012
SELF-HARDENING SLURRY WALLS
DESIGN AND QUALITY CONTROL
© LNEC 2012
INTRODUCTION
> Objectives A comprehensive literature review.
Characterization of the factors involved in
self-hardening slurry behaviour during
construction and in the long term perfor-
mance.
Definition of numerical models for
analysis and interpretation of the slurry
wall behaviour.
Definition of design principles.
Proposal of a quality control and perfor-
mance evaluation methodology.
© LNEC 2012
> A self-hardening slurry cut-off wall is a non-
-structural underground wall that serves as a
barrier to the horizontal flow of water and other
fluids.
> It is constructed with the aid of a viscous
stabilizing fluid known as slurry. Usually,
cement-bentonite slurries are used.
> In Europe, self-hardening slurries walls have
been used since 1960, particularly in seepage
control applications.
> In Portugal, the technology was first applied in
1978, in the remedial works of the Roxo Dam.
DESCRIPTION SELF-HARDENING SLURRY CUT-OFF WALL
© LNEC 2012
> Main applications of the technology.
> Construction procedures.
Excavation dewatering.
Reduction of seepage through embank-
ments or water storage structures.
Reduction of seepage of ponds and
lakes.
Subsurface dams or groundwater
reservoir.
Isolation or maintenance of water tables.
Containment of solid and liquid wastes.
Seismic cut-off.
APPLICATIONS
© LNEC 2012
> Roxo Dam
APPLICATIONS
Plan
Cross-section
Cut-off wall characteristics:
Wall length: 190 m
Maximum depth: 16.8 m
Width: 0,6 m
Self-hardening
slurry wall
Self-hardening
slurry wall Crest
Concrete gravity dam
Earth embankment
dam
Stilling
basin
Irrigation channel
Water intake
Grout curtain
Original upstream slope
© LNEC 2012
Jan. 1977
© LNEC 2012
Parede auto-endurecedora - Abril 1978
© LNEC 2012
Maio 1978
© LNEC 2012 Agosto 1980
© LNEC 2012
> Crestuma-Lever Dam
APPLICATIONS
Self-hardening
slurry wall
Self-hardening
slurry wall
Diaphragm wall
Diaphragm wall
Power plant
Crest
Navigation lock Fish
ladder
Douro
Riv
er
Stilling basin
Alluvial soil
Rock formation
Diaphragm cut-off wall
Self-hardening slurry wall
Plan Cross-section
Cut-off wall characteristics:
Wall area: 5 600 m2
Maximum depth: 40 m
Width: 0,8 m
© LNEC 2012
> Águas Industriais Dam
APPLICATIONS
Plan
Cross-section
Cut-off wall characteristics:
Wall length: 175 m
Maximum depth: 14 m
Width: 0,4 m
Bottom outlet
Original dam
Downstream
slope
Self-hardening
slurry wall
Original dam profile
Crest Heightening
section
Self-hardening
slurry wall
© LNEC 2012
> Main applications of the technology.
> Construction procedures.
APPLICATIONS
Phase 1
Phase 2
Phase 3
Phase 4
Phase 5
Etapa 6
P – Primary panel
S – Secondary panel
S
P
P
S
S
P
P P
P P
P
P
P
P
P
S P
P
P
P
P
Alternating panel method.
© LNEC 2012
> Main applications of the technology.
> Construction procedures.
APPLICATIONS
Alternating panel method.
Continuous trenching method.
© LNEC 2012
> Main applications of the technology.
> Construction procedures.
APPLICATIONS
Alternating panel method.
Continuous trenching method.
Structural diaphragm wall traditional
method.
© LNEC 2012
> Self-hardening slurry features.
> Self-hardening slurry composition.
> Chemical reactions between water, cement
and bentonite.
Water: 1 m3
Cementitious material: 100 to 350 kg
Bentonite: 30 to 60 kg
SELF-HARDENING SLURRY CHARACTERIZATION
Water (100%)
Cement
(100%)
Bentonite
(100%)
Non-setting
slurries
Semi-fluids
Cut-off slurries
Bleeding
slurries
© LNEC 2012
SELF-HARDENING SLURRY CHARACTERIZATION
CAH gel
Flocculated bentonite
particles
CSH gel
Ca2+ ions release
Hydrous silica and
alumina
(OH)- ions release
CSH gel
CAH gel
Hydrated lime
Ca(OH)2
Cement Bentonite suspension
Cement hydration
Dissociation of
hydrated lime
pH rise Modification of
the adsorbed cation
population
Dissolution of
silica and alumina of
bentonite
Shrinkage of
bentonite diffuse
double layer
Interparticle bonding
Primary
cementitous
products
Secondary
cementitous
products
Bentonite-cement clusters
Reaction with Ca2+
and (OH)- ions
> Self-hardening slurry features.
> Self-hardening slurry composition.
> Chemical reactions between water, cement and bentonite:
© LNEC 2012
> Self-hardening slurry features.
> Self-hardening slurry composition.
> Chemical reactions between water, cement
and bentonite.
SELF-HARDENING SLURRY CHARACTERIZATION
Pores
Smectite
particle
Slag
particle
Nucleus
CSH gel
(high density)
Clinker
particle CSH gel
(low density)
Bentonite-cement cluster
© LNEC 2012
PROCESSES INVOLVED IN THE FORMATION OF THE CUT-OFF WALL
MATERIAL
VISCOUS
FLUID
(Trench walls
support)
VISCOUS
SOLID
(Time-
depending
properties)
Soil contamination
Penetration
Filtration
Penetration and
Filtration
Sedimentation
Cement hydration
Self-weight
consolidation
Cement hydration
Pozzolanic reactions
EXCAVATION
PHASE
FIRST HOURS
POST-EXCAVATION
FOLLOWING
PERIOD
Cement Setting
© LNEC 2012
EXPERIMENTAL WORK
> Objectives. Identify and quantify the influence of the
slurry composition, and mixing proce-
dures upon the rheological behaviour of
the fresh slurry.
Identify and quantify the influence of the
slurry composition, spoil contamination,
curing time and surcharge loads upon the
physical, mechanical and hydraulic
behaviour of the hardened slurry.
© LNEC 2012
EXPERIMENTAL WORK
> Experimental work description:
Rheological characterization of self-
-hardening slurries.
Characterization of the “cake” formed by
filtration.
Bleeding evolution of self-hardening
slurries.
Physical characterization of hardened
slurry samples.
Compressibility and threshold stress of
hardened slurry samples.
Strength and deformability of hardened
slurry samples.
Permeability of hardened slurry samples. Slurry composition
35 kg bent. + 150 kg cement
35 kg bent. + 200 kg cement
50 kg bent. + 200 kg cement
Marsh viscosity
47 s
49 s
105 s
Marsh funnel and cup
© LNEC 2012
EXPERIMENTAL WORK
> Experimental work description:
Rheological characterization of self-
-hardening slurries.
Characterization of the “cake” formed by
filtration.
Bleeding evolution of self-hardening
slurries.
Physical characterization of hardened
slurry samples.
Compressibility and threshold stress of
hardened slurry samples.
Strength and deformability of hardened
slurry samples.
Permeability of hardened slurry samples.
Fann viscometer
© LNEC 2012
EXPERIMENTAL WORK
> Experimental work description:
Rheological characterization of self-
-hardening slurries.
Characterization of the “cake” formed by
filtration.
Bleeding evolution of self-hardening
slurries.
Physical characterization of hardened
slurry samples.
Compressibility and threshold stress of
hardened slurry samples.
Strength and deformability of hardened
slurry samples.
Permeability of hardened slurry samples.
Slurry composition
35 kg bent. + 150 kg cement
35 kg bent. + 200 kg cement
50 kg bent. + 200 kg cement
Viscosity Gel strength
8.0 cP 4.1 Pa
9.5 cP 4.6 Pa
12.5 cP 5.1 Pa
0
5
10
15
20
25
30
35
0 200 400 600 800 1000 1200
Shear rate (s-1)
Sh
ear
str
ess (
Pa)
35 kg bentonite + 200 kg cement
50 kg bentonite + 200 kg cement
35 kg bentonite + 150 kg cement
© LNEC 2012
EXPERIMENTAL WORK
> Experimental work description:
Rheological characterization of self-
-hardening slurries.
Characterization of the “cake” formed by
filtration.
Bleeding evolution of self-hardening
slurries.
Physical characterization of hardened
slurry samples.
Compressibility and threshold stress of
hardened slurry samples.
Strength and deformability of hardened
slurry samples.
Permeability of hardened slurry samples.
Filter press
© LNEC 2012
EXPERIMENTAL WORK
> Experimental work description:
Rheological characterization of self-
-hardening slurries.
Characterization of the “cake” formed by
filtration.
Bleeding evolution of self-hardening
slurries.
Physical characterization of hardened
slurry samples.
Compressibility and threshold stress of
hardened slurry samples.
Strength and deformability of hardened
slurry samples.
Permeability of hardened slurry samples.
35 kg bentonite + 200 kg cement
0
50
100
150
200
250
0 2 4 6 8 10
Sqrt[time] (min0.5)
Fil
trate
lo
ss (
ml)
“Cake” permeability: 1.7x10-8 m/s
“Cake” unit mass: 1240 kg/m3
“Cake” water content: 122%
“Cake” void ratio: 3.0
© LNEC 2012
EXPERIMENTAL WORK
> Experimental work description:
Rheological characterization of self-
-hardening slurries.
Characterization of the “cake” formed by
filtration.
Bleeding evolution of self-hardening
slurries.
Physical characterization of hardened
slurry samples.
Compressibility and threshold stress of
hardened slurry samples.
Strength and deformability of hardened
slurry samples.
Permeability of hardened slurry samples.
Composition Bleeding
35 kg bent. + 150 kg cement: 6%
35 kg bent. + 200 kg cement: 5 to 6%
50 kg bent. + 200 kg cement: 2%
© LNEC 2012
EXPERIMENTAL WORK
> Experimental work description:
Rheological characterization of self-
-hardening slurries.
Characterization of the “cake” formed by
filtration.
Bleeding evolution of self-hardening
slurries.
Physical characterization of hardened
slurry samples.
Compressibility and threshold stress of
hardened slurry samples.
Strength and deformability of hardened
slurry samples.
Permeability of hardened slurry samples.
Slurry composition
35 kg bent. + 150 kg cement
35 kg bent. + 200 kg cement
50 kg bent. + 200 kg cement
35 kg bent. + 150 kg cement
35 kg bent. + 200 kg cement
50 kg bent. + 200 kg cement
35 kg bent. + 150 kg cement
35 kg bent. + 200 kg cement
Unit mass (average)
1145 kg/m3
1155 kg/m3
1165 kg/m3
Water content
395 to 445%
305 to 350%
300 to 325%
wL IP
128% 22%
151% 38%
© LNEC 2012
EXPERIMENTAL WORK
> Experimental work description:
Rheological characterization of self-
-hardening slurries.
Characterization of the “cake” formed by
filtration.
Bleeding evolution of self-hardening
slurries.
Physical characterization of hardened
slurry samples.
Compressibility and threshold stress of
hardened slurry samples.
Strength and deformability of hardened
slurry samples.
Permeability of hardened slurry samples.
35 kg bentonite + 200 kg cement
0.0
0.1
0.2
0.3
0.4
0.5
0.6
0.7
0.8
0.9
1.0
1 10 100 1000 10000
Vertical pressure (kPa)
e /
e0
4 weeks curing
© LNEC 2012
EXPERIMENTAL WORK
> Experimental work description:
Rheological characterization of self-
-hardening slurries.
Characterization of the “cake” formed by
filtration.
Bleeding evolution of self-hardening
slurries.
Physical characterization of hardened
slurry samples.
Compressibility and threshold stress of
hardened slurry samples.
Strength and deformability of hardened
slurry samples.
Permeability of hardened slurry samples.
35 kg bentonite + 200 kg cement
0.0
0.1
0.2
0.3
0.4
0.5
0.6
0.7
0.8
0.9
1.0
1 10 100 1000 10000
Vertical pressure (kPa)
e /
e0
4 weeks curing 8 weeks curing
© LNEC 2012
EXPERIMENTAL WORK
> Experimental work description:
Rheological characterization of self-
-hardening slurries.
Characterization of the “cake” formed by
filtration.
Bleeding evolution of self-hardening
slurries.
Physical characterization of hardened
slurry samples.
Compressibility and threshold stress of
hardened slurry samples.
Strength and deformability of hardened
slurry samples.
Permeability of hardened slurry samples.
35 kg bentonite + 200 kg cement
0.0
0.1
0.2
0.3
0.4
0.5
0.6
0.7
0.8
0.9
1.0
1 10 100 1000 10000
Vertical pressure (kPa)
e /
e0
4 weeks curing 8 weeks curing
12 weeks curing
© LNEC 2012
EXPERIMENTAL WORK
> Experimental work description:
Rheological characterization of self-
-hardening slurries.
Characterization of the “cake” formed by
filtration.
Bleeding evolution of self-hardening
slurries.
Physical characterization of hardened
slurry samples.
Compressibility and threshold stress of
hardened slurry samples.
Strength and deformability of hardened
slurry samples.
Permeability of hardened slurry samples.
0
50
100
150
200
250
300
350
400
0 2 4 6 8 10 12 14 16 18 20
e (%)
s' 1
- s
' 3 (
kP
a)
0
50
100
150
200
250
300
350
400
DU
(kP
a)
24 kPa 100 kPa 400 kPa
© LNEC 2012
EXPERIMENTAL WORK
> Experimental work description:
Rheological characterization of self-
-hardening slurries.
Characterization of the “cake” formed by
filtration.
Bleeding evolution of self-hardening
slurries.
Physical characterization of hardened
slurry samples.
Compressibility and threshold stress of
hardened slurry samples.
Strength and deformability of hardened
slurry samples.
Permeability of hardened slurry samples.
0
100
200
300
400
0 100 200 300 400
p' (kPa)
s' 1
- s
' 3 (
kP
a)
M=2.5
M=
0
20
40
60
80
100
0 20 40 60 80 100
p' (kPa)
s' 1
- s
' 3 (
kP
a)
M=2.5
M=3
M=3
© LNEC 2012
EXPERIMENTAL WORK
> Experimental work description:
Rheological characterization of self-
-hardening slurries.
Characterization of the “cake” formed by
filtration.
Bleeding evolution of self-hardening
slurries.
Physical characterization of hardened
slurry samples.
Compressibility and threshold stress of
hardened slurry samples.
Strength and deformability of hardened
slurry samples.
Permeability of hardened slurry samples. 1.E-09
1.E-08
1.E-07
1.E-06
3 5 7 9
Void ratioC
on
du
cti
vit
y c
oeff
icie
nt
(m/s
)
35 kg bentonite + 200 kg cement
50 kg bentonite + 200 kg cement
35 kg bentonite + 150 kg cement
© LNEC 2012
EXPERIMENTAL WORK
> Experimental work description:
Rheological characterization of self-
-hardening slurries.
Characterization of the “cake” formed by
filtration.
Bleeding evolution of self-hardening
slurries.
Physical characterization of hardened
slurry samples.
Compressibility and threshold stress of
hardened slurry samples.
Strength and deformability of hardened
slurry samples.
Permeability of hardened slurry samples. 1.E-09
1.E-08
1.E-07
1.E-06
0 200 400 600 800 1000
Effective stress (kPa)C
on
du
cti
vit
y c
oeff
icie
nt
(m/s
)
35 kg bentonite + 200 kg cement
50 kg bentonite + 200 kg cement
35 kg bentonite + 150 kg cement
© LNEC 2012
FUTURE RESEARCH
> Feasibility study regarding the use of
piezocone penetration tests for assessing the
integrity of self-hardening slurry cut-off walls,
but also for determining permeability, strength
and compressibility of the slurry "in situ".
> Feasibility study regarding the use of geophy-
sical tests in assessing the integrity of self-
-hardening slurry cut-off walls and also in the
characterization of its permeability.
> Sedimentation and self-weight consolidation
analysis of self-hardening slurries using a
consolidation column equipped with a gamma
densimeter.
> Detailed study concerning the influence of
slurry setting upon the development of slurry
filtration, penetration and sedimentation
processes.
© LNEC 2012 © LNEC 2012
Research Perspectives in Embankment Dams at LNEC
Laura Caldeira [email protected]
Head of the Geotechnique Department
Dam World Conference 8-11th October 2012 Maceio, Brazil