Dr. Arindam Dey Presentations... · Sherard (1973) Suggested that the existing closed cracks can...
Transcript of Dr. Arindam Dey Presentations... · Sherard (1973) Suggested that the existing closed cracks can...
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Short Course
Finite Element Analysis of Static and Dynamic
Soil-structure Interaction of Geosystems
Department of Civil Engineering, NIT Warangal
Dr. Arindam DeyAssociate Professor
Geotechnical Engineering Division
Department of Civil Engineering
IIT Guwahati
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Introduction Dams are structural barriers
Construction of earthen dams in the north-eastern region of
India
-regional flood management measure
-incessant rainfall and encompasses around 12% of the
total flood area of the country (Das et al., 2017)
Chief drawback of earthen dams
-prone to get overtopped
-seepage, internal erosion, piping, clogging, cracking
Prevention of failures of earthen dams and embankments
Drainage layers -expected to protect the earthen dams
Instability of dams due to hydraulic fractures (Yang et al.,
2004) 207-01-2021 Short Course, NIT Warangal
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Failures of Earthen Dams Across the World
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Fenton and Griffiths (1997) The influence of spatial variability of the permeability of the dam on the development of internal
hydraulic gradients was attempted. It was found that the spatial variability of the permeability does
lead to a probability of higher internal gradients.
Reddi et al. (2000) Studied the reduction of permeability of the filters due to clogging. It was observed that an increase
in influent particle concentration results in faster reduction of the filter permeability. However, the
filter performance was not affected by the flow rate.
Reboul et. al. (2010) A method was proposed to compute the constriction size distribution of model granular filters taking
into account the relative density of the material.
Sherard (1973) Suggested that the existing closed cracks can jack open under certain conditions of reservoir pressure
acting on the upstream face of the core in a zoned earthen dam.
Vaughan (1976) Introduced the term “wet cracks” for the cracks formed during or after the reservoir rise-up. The
occurrence of tensile failure was observed when the seepage pressure was applied rapidly to an
already existing initial crack, or imperfection, leading to the failure of the dam.
Leonards and Davidson (1984),
Mesri and Ali (1988)
Defined saturation settlement as the cause of core cracking due to hydraulic fracturing. Saturation
settlement develops during the filling of a reservoir, when the poorly compacted soil or pervious
zones and layers (comprising loose material) becomes saturated and consolidates under their own
weight, before the dry or denser soil arches over it and gets the chance to saturate and collapse. A
discontinuity or a crack is developed along the position of the phreatic line. Any subsequent increase
in water level allows the entry of water into this crack enabling the erosion to occur. Such collapse
can be either sudden or gradual.
Past Studies
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Basic Methodology Considered in Numerical Simulation
Seepage Analysis : Seep/w module
Deformation Analysis : Sigma/w module
Stability Analysis : Slope/w module
𝜕
𝜕𝑥𝑘𝑥𝜕𝐻
𝜕𝑥+
𝜕
𝜕𝑦𝑘𝑦
𝜕𝐻
𝜕𝑦+ 𝑄 =
𝜕𝜃
𝜕𝑡
𝑋 = 𝐸𝜆𝑓 𝑥 , Morgenstern and Price (1965)
b s nK a F F F F
where, [K] is the element characteristic (or stiffness) matrix, {a} is the nodal incremental displacement vector, {F} is the applied nodal incremental
force, {Fb} is the incremental body force vector, {Fs} is the force vector due to surface boundary incremental pressures, and {Fn} is the vector of
concentrated nodal incremental forces.
where, f(x) is a function, λ is a scaling factor, E is the interslice normal force and X is the interslice shear force
where, H is the total head, kx, ky are the hydraulic conductivities in the Cartesian directions, Q is the applied boundary flux, θ is the volumetric water
content, and t is the elapsed time.
07-01-2021 Short Course, NIT Warangal
GeoStudio 2012
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• A fully-automated robust unstructured meshing (employing element compatibility)
-generated on the basis of the defined geometry,
-can be altered or subjected to further local or global refined as per the necessity
• Different type of finite element mesh patters namely,
-Quads and Triangles, Triangles only, Rectangular grid of quads, Triangular grid of Quads /
Triangles
• Unstructured mesh comprising ‘quad and triangle’ is utilized
-selected element type conforms to the 4-noded quadrilaterals and 3-noded triangles,
respectively
Seep/w Simulations
-constant total head (H) and total head (H|t|) boundary conditions
Sigma/w Simulations
-base of the model is restrained from displacement in both the directions,
-far lateral boundaries are restrained from horizontal displacement but are kept free from
vertical restraint
-fluid pressure boundary is used to specify the elevation of the water surface
Slope/w Simulations
-‘Entry and Exit’ method of defining the slip circles and identify the critical slip circle is used
Meshing and Boundary Conditions
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Seep/w
The embankment and core
-‘Saturated / Unsaturated’ material model
The foundation
-‘Saturated Only’ material model
Sigma/w
Linear Elastic material model
Elastic Perfectly Plastic material model
Slope/w
Mohr-Coulomb failure criterion
Material models
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Stages of Analyses
Steady state seepage analysis : To set up the initial pore water pressures and total head conditions
In-situ analysis : To set up the initial stress conditions
Load/Deformation analysis : To simulate the staged construction of dams
Coupled Stress/PWP analysis : To generate - different drain clogging scenarios, reservoir operating conditions
Stability analysis : Stress based in Slope/w07-01-2021 Short Course, NIT Warangal
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Numerical Modeling of Earthen Dam: Validation With Field Data
Evolution of Finite Element Method (FEM) from a research tool into a daily engineering tool
-application for the analysis of geotechnical engineering problems
Many advantages provided by the usage of FEM, but it also suffers from some limitations
-simplified representation of the actual soil behaviour forms one of the main limitations
Some features of soil behaviour will not be captured by the model
Validation of the numerical models with the actual field scenario becomes essential
Validation confirms the accuracy with which the model captures the reality
Numerical model simulating reservoir drawdown condition in an earthen dam
was validated with real field condition
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MODEL FOR THE STUDY(Paton and Semple, 1961)
Typical dam section of Glen Shira Dam,
Scotland (Pinyol et. al., 2016)
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c
(kPa)
φ
(degree)
γ
(kN/m3)
E
(kPa)
k
(m/s)
Morainic fill 15 25 18 5000 10-8
Graded filter 0 25 16 10000 10-1
Core wall 12 20 18 25000 10-18
Rockfill 0 30 16 15000 10-3
Foundation 12 18 20 30000 10-16
MATERIAL PROPERTIES(USBR 2003; USBR 2014; Pinyol et. al., 2016;
Paton and Semple, 1961; Geotechdata.info, 2013)
Rate of reservoir drawdown (function of total head with time)07-01-2021 Short Course, NIT Warangal
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RESULTS AND DISCUSSIONS
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Average percentage difference between the measured values
and Geostudio simulations is 10%
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(a) (b)
(c)
• Total head contour values and distribution
• Results from Geostudio gives very similar nature
• Compared with the computed and interpolated
values
Code_Bright (Alonso & Pinyol, 2016) Paton and Semple, 1961
Geostudio results
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Dams and seepage
50% of all dam failures are attributed to excess seepage (Fell and Foster, 2000)
Application of filters and drains have been a common method to control the seepage flow (USBR, 2003)
But what if these drains and filters undergo clogging…
Dam failures associated drain clogging (Vaughan and Soares 1982; Von Thun 1985; Peck 1990; Vick 1996)
Fonte Santa tailings dam in Northeast Portugal, failure on November 27, 2006 (Franca et al., 2008).
Clogging is a major public concern limiting the lifetime of the structures
In earthen dams clogging is a serious issue, however few works are done to study the response of the dams due to clogging
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RESPONSE OF HOMOGENEOUS EARTHEN DAM SUBJECTED TO
CLOGGING OF DRAINAGE BLANKET
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MODEL GEOMETRY Earth dam models with dimensions as per IS 12169:1987
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c
(kPa)
φ
(degree)
γ
(kN/m3)
E
(kPa)
k
(m/s)
Embankment 10 25 20 15000 10-7
Foundation 15 20 20 30000 10-10
Drain 2 30 18 12000 10-2
Clog 10 25 20 15000 10-7
MATERIAL PROPERTIES
(IS 12196:1987; USBR 2014; NAVFAC Design Manual 7.2, 1982, Geotechdata.info, 2013)
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SCENARIOS INVESTIGATED IN THE STUDY
Dam without any drainage blanket (NDC)
Dam with fully functional drainage blanket (FDC)
Dam with clogged drainage blanket (CDC)
Different Forms of Clogging
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Steady state condition of reservoir operation
• Horizontal Drainage Blanket
Pore water pressure near the toe
Fully functional drainage blanket condition (FDC)
Without drainage blanket condition (NDC)
Clogged drainage blanket condition (CDC)
RESULTS AND DISCUSSIONS
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Steady state condition of reservoir operation
• Horizontal Drainage Blanket
Excess pore water pressure contours for fully functional drain condition (FDC)
Excess pore water pressure contours for clogged drain condition (CDC) 16
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Contours for CDC (a) Gradient (b) Velocity
Contours for FDC (a) Gradient (b) Velocity
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Steady state condition of reservoir operation
• Inclined Drainage Blanket
Pore water pressure near the toe
Without drainage blanket condition (NDC)
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Fully functional drainage blanket condition (FDC)
Contours for FDC (a) Gradient (b) Velocity
Contours for CDC (a) Gradient (b) Velocity
Clogged drainage blanket condition (CDC)
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(a) Horizontal drainage (b) Inclined drainage
Pore Water Pressure Variation
Inward Outward Upward Downward Random
Inward
Random
Outward
Pore Water Pressure (PWP)
(kPa)
Horizontal drainage blanket
50 44 29.73 44 33.74 29.82
Inclined drainage blanket
34 0.50 7.99 0.58 0.61 1.57
Pore-water
pressure (kPa)
Downstream
Slope
Deformation (m)
Base Settlement
(m)
Exit Gradient
Horizontal drainage blanket (Inward Clogging)
50 0.099 0.09 2.4
Inclined drainage blanket (Inward Clogging)
34 0.08 0.07 0.95
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(a)
(b)
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Transient state condition of reservoir operation
• Drawdown : Rate 1.5 m/day
Pore water pressure at the base of the
embankment at 150th day
Horizontal drainage blanket
Inclined drainage blanket
Excess pore water pressure for clogged drain at the end of
drawdown; i.e., on 6th day
Horizontal drainage blanket
Inclined drainage blanket
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Transient state condition of reservoir operation
• Rise-up : Rate 1.5 m/day
Inclined drainage blanket
Pore water pressure at the base of the
embankment at 150th day Excess pore water pressure for clogged drain at the end of rise
up; i.e., on 6th day
Horizontal
drainage blanket
Inclined
drainage blanket
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Horizontal drainage blanket
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Stability values for inclined drainage blanket
NDC FDC
CDC
Stability analysis
Stability values for horizontal drainage blanket
1.241
FDC
CDC
NDC
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Inclined drainage blanketHorizontal drainage blanket
Overall, no definite comparative trend could be observed from different forms of clogging
-different forms of clogging would affect the stability in their own unique way
-inward clogging is observed to yield lowest stability values
-random clogging gives highest stability
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Stability analysis
Variation of
FoS for
drawdown
case
Variation of
FoS for rise up
case
Upstream faceUpstream face
Downstream face Downstream face 2407-01-2021 Short Course, NIT Warangal
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Rate of Clogging
1 m/day
0.01 m/day
1 m/day
0.01 m/day
1 m/day
0.01 m/day
Rise up DrawdownSteady State
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HYDRAULIC FRACTURING AND CRACKING OF HOMOGENEOUS
EARTHEN DAMS
Detrimental effects of cracks on earthen dams and embankments was first observed by Casagrande (1950)
Causes of different crack formation in earthen dams was summarized by Sherard (1973)
-differential settlement due to the presence of elements comprising of different deformability characteristics
-hydro mechanical forces causing redistribution of stresses in the dam during rapid filling and emptying of the reservoir
-presence of soils with piping instability placed in the body of the earth dam and in the core of earth-rock dams
-foundation comprising of compressible, or piping-unstable soils; marked changes in the topography of the footing and side
abutments of the dam
-cracking is also caused by seismic forces
Most often cracks are formed by a combination of several of the aforementioned causes.
Identify the crack locations at the end of dam construction and during its operational stage
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Analysis for Case I (Sequential Dam Construction in Single and Multiple layers)
Simulation of sequential dam construction was carried out using the Load/Deformation analysis
-placing the embankment fill either in single layer or
-multiple layers
For the multiple layer analysis, the total embankment height of 15 m was divided into five smaller lifts
-the height of each lift being 3 m
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MODEL FOR THE PRESENT STUDY
(IS 12196:1987; USBR 2003; USBR 2014; NAVFAC Design Manual 7.2, 1982, Geotechdata.info, 2013)
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Analysis for Case II (Operational Stage: 2.8 m/day; Reservoir Rise Up and Drawdown Condition)
After attaining steady state condition Before attaining steady state condition28
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• Possibility of hydraulic fracturing in earthen dams based on:
-differential settlement after construction
• Other pattern was the case where pore water pressure comes into play with reservoir filling
• Pore water pressure in the core increases which results in the decrease of the effective stress (σ’3)
• It becomes equal to the effective tensile strength (p’t) to jack open latent cracks.
RESULTS AND DISCUSSIONS
Figure (a) : decrease in σ3 resulted in the growth of initial stress circle (I) on the left side which finally touches the failure
envelop at the circle (II) to open tension cracks
Figure (b) : initial stress circle (I) touched the failure envelope at
the circle (II) by shifting towards the left without any change in
the diameter gives a criterion in this case: σ’3 < - p’t
Ohne and Narita, 1977
during dam construction during reservoir operation
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• Maximum negative stress for upstream slope of the dam simulated
-with a single lift was 29.5 kPa at a height of 17.02 m
-with multiple lift was 24.84 kPa at a height of 17. 28 m
• Maximum negative stress for downstream slope of the dam simulated
-with a single lift was 29.05 kPa at a height of 17.05 m
-with multiple lift 25.05 kPa at a height of 17. 28 m
• Maximum negative stresses occurred at height of approximately 17 m
to 17.3 m
-approximately ½ of the height of the embankment
-makes it the most vulnerable location for crack initiation
a) Upstream face
b) Downstream face
Analysis for Case I (Sequential Dam Construction in Single and Multiple layers)
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Analysis for Case II (Operational Stage: Reservoir Rise Up Condition)
Possibility of hydraulic fracturing along the upstream face
-at around 0.2-0.25 times the embankment height measured from
the base
Possibility of hydraulic fracturing does not
exist along downstream face
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Analysis for Case II (Operational Stage: Reservoir Drawdown Condition)
After the steady-state phreatic surface is attained
Upstream face
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Downstream face
0.5-0.75 times the height earthen dam, measured
from its basePossibility of crack occurrence is minimal
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Investigation for hydraulic fracturing during reservoir drawdown condition before the steady-state is
attained (a) upstream face (b) downstream face 33
• Substantial possibility of hydraulic fracturing along the upstream face
-significant release of PWP that accumulated during the reservoir rise-up
-constant reservoir level for a certain duration
-height of 9 m height from the base of the earthen dam
-approximates to 0.6 times the height of the dam measured from the base
• Along the downstream face of the dam
-no favorable conditions leading to hydraulic fracturing
-migration of phreatic surface within the earthen dam did not attain a
steady state
(a)
(b)
Before the steady-state phreatic surface is attained
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• Hydraulic fracturing in dams has an inherent difficulty
-hydraulic fractures observation by direct visualization is not possible
-open only when the water pressure comes into play
-within the dam
• Dam failures due to hydraulic fracture
-development of high pore water pressure downstream of the core
• Teton Dam failure failed just within few hours after the first leakage was
spotted
• Cause of initial leak is nearly impossible as erosion would destroy any proof
• Understanding the initiation of core cracking is challenging
-numerically investigate the possibility of core cracking during different reservoir conditions by hydraulic fracturing
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HYDRAULIC FRACTURING AND CRACK PROPAGATION IN ZONED
EARTHEN DAMS WITH A CENTRAL IMPERVIOUS CORE
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c
(kPa)
φ
(degree)
γ
(kN/m3)
E
(kPa)
k
(m/s)
Shell 5 28 18 15000 10-6
Foundation 15 20 20 30000 10-10
Core 10 32 20 9000 10-8
MATERIAL PROPERTIES(IS 12196:1987; USBR 2003; USBR 2014; NAVFAC
Design Manual 7.2, 1982, Geotechdata.info, 2013)
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MODEL GEOMETRY Earth dam models with dimensions as per IS 12169:1987
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• Just at the initial stages of the reservoir filling
- possibility of hydraulic fracturing is substantially less
-build-up of pore-water pressure
-magnitudes of minor principal stress
-case of corresponding plots for 5th day
• Just after the completion of the reservoir rise-up
-possibility of hydraulic fracturing increases
-pore-water pressure increases
-approaches the magnitude of the minor principal
stress
-can be observed from the comparative plots of 38th
day
• After long time from the completion of reservoir rise-up
-slow dissipation of excess pore-water pressure
-very low conductivity of the material of central core
-no changes in pore-water pressure and total stress
profilesVariation of minimum total stress and PWP along the upstream
face of the central core
None of the profile indicate a conclusive occurrence of hydraulic fracturing along the upstream face of the central core
RESULTS AND DISCUSSIONS
Analysis for reservoir rise-up condition (0.5 m/day)
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• Define a modified limiting condition that can be considered for the conceptual detection of hydraulic fracturing
-the temporal variation of the stress ratio (ratio between the minimum total stress and PWP) is investigated
• As per the criterion of Ohne and Narita (1977)
-hydraulic fracturing will initiate
-stress ratio would be equal to or greater than 1 (one)
• Approximately until the 25th day, the stress ratio is transient
-development of the PWP
• From the 35th day, i.e. after the reservoir rise-up is complete
-stress ratio increases
-arrives at a stable magnitude
-stabilization of the pore-water pressure fluctuations
Variation of stress ratio with elevation for the time elapsed after
reservoir rise-up
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(a) Variation of maximum stress ratio with elapsed time (b) Variation of elevation of occurrence of maximum stress ratio with elapsed time
(a)
(b)
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• Stress ratio increases with time and attains a stable magnitude of 0.8
-considering different uncertainties associated with dam
construction
-hydraulic fracturing can be reasonably said to initiate
-stress ratio at the upstream face of the core is 0.8
• Identify the tentative location
-maximum stress ratio occurred at an elevation of 11.25 m from
the base of the dam
-approximately at 3/4th the height of the dam, measured from the
base
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Strain contours on 38th day
Seepage velocity at Point
K along the upstream face
of the core
Hydraulic gradient contour on 38th day
Strain concentration occurred on the upstream core
face
-at about 3/4th of the height of the dam,
measured from the base
High gradients along with high seepage velocity
gives sufficient favourable conditions for internal
erosion of the dam core
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• Figure (a) shows that hydraulic fracturing is possible
-only at the start of the drawdown condition
-as seen for the 5th day
• Location of maximum possibility of hydraulic fracture
-i.e., 3/4th height of earthen dam
-measured from the base
• As the drawdown progressed the pore water pressure decreased
• Figure (b) shows that hydraulic fracturing is not possible
Analysis for reservoir drawdown condition (0.5 m/day)
Hydraulic fracturing at the upstream of central core during reservoir drawdown condition (a) after attaining steady state
condition (b) before attaining steady state condition 40
(a)(b)
(a)
(b)
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Non-homogenous earth fill dam
Load Transfer or Arching Phenomenon
-pore water pressure can become more than total stress
within core (Sherard 1991; Ono and Yamada 1993)
Hydraulic Fracturing
-differential settlement
-increase of pore water pressure in the core
Internal erosion
Efficacy of Drainage Blankets in Zoned
Earthen Embankment Dams
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Ohne and Narita, 1977
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Phreatic surface location
Horizontal drainage blanket (FDC) Inclined drainage blanket (FDC)
No drainage blanket condition (NDC)
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Efficacy of Drainage Blankets in Zoned Earthen Embankment Dams
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Internal gradient Seepage velocity (m/days) 43
Internal gradient and seepage velocities
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• Internal gradient varies along the meandering seepage path
-owing to different amounts of head loss at different locations along the path
-internal gradient that might lead to the initiation of internal erosion may be as low as 0.02-0.08 for particularly
susceptible soils (Schmertmann, 2000)
-can be much lower than critical exit gradient (often considered as 1.0)
• Location of occurrence of maximum internal gradients is same for all the cases
-contact interface of the core and the downstream shell or the inclined drainage blanket
• Developed internal gradient is observed to be sufficiently high
• Combination of developed internal gradient and seepage velocities will initiate the internal erosion
-governed by many additional factors, most importantly the soil gradation
-investigation of internal erosion is out of scope of the present dissertation work
• Presence of the drainage blanket in a zoned dam having an impervious foundation
-no role in preventing the potential risk for internal erosion within the core
• Influence of drainage blankets in the case of a cracked core is investigated
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Core with a crack (No drainage blanket condition)
Core with a crack (Horizontal drainage blanket ) Core with a crack (Inclined drainage blanket )
Presence of drainage blankets
-prevents the rise of the phreatic surface such that it does not intersect the downstream face
-hydraulic fracturing or cracking in the core puts the operation of the dam at risk
-presence of the drainage blanket could be effective in protecting the downstream
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However, in reality, the crack would evolve through the central core,
rather than following a predefined path
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Identification of crack propagation path
(a) Nodal points demarcating maximum stress ratio in the
region of maximum strain on the 38th day (b) Demarcated
region assigned with high permeable material to simulate virtual
flow path of water due to cracking
• Propagation path was traced by identifying the nodal points
-around the location of crack initiation
-where the stress ratio was approximately equal to 1
in the region of maximum strain contours
• Process is initiated from the 38th day
-that demarcates the possible initiation of core
cracking
• Once demarcated, a region comprising of high permeable
material was assigned in the numerical simulation
-thereby implying nearly free percolation of water
-through the region as if it is the preferred path after
the crack is virtually simulated
(a)
(b)
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Simulation was completed for the 38th day
-the corresponding strain contours, gradient and
velocity were checked
-to develop the idea of successive demarcation
-the nodal points with maximum stress ratio
(approximately equal to 1) for the next day, i.e. the
39th day
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• Identification of the possible crack enhancement
region on the 39th day
-as earlier, a high permeable material is
assigned
-the analyses is carried forward for the
successive days
• As the analysis is conducted progressively for
successive days,
-the path of crack propagation is identified
through the core of the dam
• Analysis is stopped once the crack propagates and
merges with the downstream face of the central
core
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Providing a simplistic modeling technique for simulating various possible mechanisms of drainage
blanket clogging and their influence on the stress-flow-deformation response of earthen dams.
Showcasing the importance and efficacy of drainage blankets, especially the inclined chimney
drainage blankets, in establishing the continuous functioning and long-term safety of earthen dams,
even after the same gets partially clogged.
Highlighting the importance of the drainage blankets in ascertaining the performance of a zoned
earthen dam with the presence of a cracked central impervious core.
Based on numerical modeling and standard stress-PWP criterion, assessing the tentative locations of
initiation of cracking and hydraulic fracturing of the shell and core of homogeneous and zoned
earthen dams, respectively.
Tracing and identifying the path of crack propagation through the central impervious core through
recursive finite element analysis.
MAJOR CONTRIBUTIONS
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Journals
1. Talukdar, P. and Dey, A. (2021) “Finite element analysis for identifying locations of cracking and hydraulic fracturing in
homogeneous earthen dams” International Journal of GeoEngineering (Springer). (Accepted)
2. Talukdar, P. and Dey, A. (2019) “Hydraulic failures of earthen dams and embankments” Innovative Infrastructure Solutions
(Springer), Vol. 4, Paper No. 42, pp. 1-20.
Book Chapters
1. Talukdar, P. and Dey, A. (2018) “Effect of Varying Geometrical Configuration of Sheet Piles on Exit Gradient and Uplift Pressure”;
In book: Geotechnical Applications Chapter: 15 Publisher: Springer, Singapore.
2. Talukdar, P. and Dey, A. (2018) “Sequential drawdown and rainwater infiltration based stability assessment of earthen dams”
Advances in Computer Methods and Geomechanics, pp 541-551.
3. Talukdar, P. and Dey, A. (2017) “Response of Earth Dams to Toe Drain Clogging” (Accepted for Book Chapter in Springer
Publications).
4. Talukdar, P. and Dey, A. (2018) “Numerical modeling of earthen dam: Validation with field data” (Accepted for Book Chapter in
Springer Publications).
5. Talukdar, P. and Dey, A. (2018) “Influence of the rate of construction on the response of embankment on PVD improved soft
ground” (Accepted for Book Chapter in Springer Publications).
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PUBLICATIONS
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Conference: National/International
1. Talukdar, P. and Dey, A. (2018) “Sequential drawdown and rainwater infiltration based stability assessment of earthen dams” International IACMAG
Symposium, Gandhinagar, India, Paper No. 236, pp. 1-11.
2. Talukdar, P. and Dey, A. (2018) “Numerical modeling of earthen dam: Validation with field data” International Conference on Infrastructure
Development (ICID), Jorhat, India.
3. Talukdar, P. and Dey, A. (2018) “Influence of the rate of construction on the response of embankment on PVD improved soft ground” Indian
Geotechnical Conference (IGC-2018), Bangalore, India, pp. 1-7
4. Talukdar, P. and Dey, A. (2017) “Response of Earth Dams to Toe Drain Clogging”, Indian Geotechnical Conference, IGC, Department of Civil
Engineering, IIT Guwahati, India, pp. 1-4.
5. Talukdar, P., Bora, R. and Dey, A. (2017) “Finite Element Based Identification of the Triggering Mechanism of a Failed Hill Slope” 15th International
Conference of International Association for Computer Methods and Advances in Geomechanics (IACMAG), Wuhan, China, pp. 1-11.
6. Talukdar, P., Bora, R. and Dey, A. (2016) “Stability analysis of ash pond dyke under static, pseudo-static and seismic conditions” 1st International
Conference on Civil Engineering for Sustainable Development – Opportunities and Challenges (CESDOC), Guwahati, India, pp. 1-6.
7. Talukdar, P., Bora, R. and Dey, A. (2016) “Forensic investigation of the failure of a marginally stable hill slope” 5th International Conference on Forensic
Geotechnical Engineering, Bangalore, India, pp. 389-400.
8. Talukdar, P. and Dey, A. (2016) “Effect of varying geometrical configuration of sheet piles on exit gradient and uplift pressure” Geotechnology Towards
Global Standards, Indian Geotechnical Conference, IGC 2016 Department of Civil Engineering, IIT Madras, India, pp. 1-4.
5107-01-2021 Short Course, NIT Warangal
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Relevant References
Alonso, E. E. and Pinyol, N. M., 2016. Numerical analysis of rapid drawdown: Applications in real cases. Water Science and
Engineering, 9(3): 175-183.
Das, K., Saikia, M. D, Kalita, U. C., 2017. Modelling of Embankment Breaching with Special Reference to Barak Valley, Assam.
Indian Geotechnical Conference, IGC, Department of Civil Engineering, IIT Guwahati, India, 1-4.
Foster, M. A., Fell R. and Spannagle M., 2000a. The statics of embankment dam failures and accidents, Canadian Geotechnical
Journal, 37(5), pp. 1000-1024.
Foster, M. A., Fell R. and Spannagle M., 2000b. A method for estimating the relative likelihood of failure of embankment Paper
No. 3.03a 7 dams by internal erosion and piping, Canadian Geotechnical Journal, 37(5), pp. 1025-1061.
IS 12169 (1987) Criteria for Design of Small Embankment Dams, B.I.S.
Pinyol, N. M., Alonso, E. E. and Olivella, S., 2008. Rapid drawdown in slopes and embankments, Water Resource Research, 44,
W00D03, doi:10.1029/2007WR006525.
Seed, H. B. and Duncan, J. M. 1981. The Teton Dam Failure-a Retrospective Review, 0th ICSMFE, Stockholm, Sweden, vol. 4,
214-238.
United States Bureau of Reclamation 2003. Design of Small Dams, Oxford & IBH, New Delhi.
5207-01-2021 Short Course, NIT Warangal
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Acknowledgment
07-01-2021 Short Course, NIT Warangal 53
Dr. Priyanka Talukdar
Research Assistant
Ryerson University, Canada
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07-01-2021 Short Course, NIT Warangal 54
Thank You for Patient Hearing
http://www.iitg.ac.in/arindam.dey/homepage/index.html#
https://www.researchgate.net/profile/Arindam_Dey11