Sustainable Geotechnics – Investigations for Geoenvironmental Engineering Applications by by Dr. G. JANARDHANAN Ph.D(USA)., E. I Centre for Environmental Management National Institute of Technical Teachers Training & Research Chennai, India 18 th to 22 nd October 2011
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Sustainable Geotechnics –
Investigations for Geoenvironmental Engineering Applications
byby
Dr. G. JANARDHANAN Ph.D (USA)., E. I
Centre for Environmental Management
National Institute of Technical Teachers Training & Research
Chennai, India
18th to 22nd
October 2011
Disclaimer:
In this lecture, contents expressed are purely my personal technical
perspective…it does not represent the organization to which I am
affiliated.
Objectives of the lecture
• To introduce the concept of geoenvironmental testing,
placing it within the framework of sustainable
geotechnics.
• To outline the theory with an emphasis on why it was
introduced and how it has evolved.
• To introduce the concept of geoenvironmental testing,
placing it within the framework of sustainable
geotechnics.
• To outline the theory with an emphasis on why it was
introduced and how it has evolved.introduced and how it has evolved.
• To describe the purpose, principles and process of
geoenvironmental investigations.
• To review some contemporary issues of
geoenvironmental investigations and sustainable
geotechnics.
introduced and how it has evolved.
• To describe the purpose, principles and process of
geoenvironmental investigations.
• To review some contemporary issues of
geoenvironmental investigations and sustainable
geotechnics.
“Engineers have a significant role in planning,designing, building and maintaining asustainable future. We provide the bridgebetween science and society, in this role; wemust participate in interdisciplinary teams,
“Engineers have a significant role in planning,designing, building and maintaining asustainable future. We provide the bridgebetween science and society, in this role; wemust participate in interdisciplinary teams,must participate in interdisciplinary teams,applying technology to issues and challengesthat require environmentally sustainablestrategies and solutions.”
- American Society of Civil Engineers (2001).
must participate in interdisciplinary teams,applying technology to issues and challengesthat require environmentally sustainablestrategies and solutions.”
- American Society of Civil Engineers (2001).
Questions to be answered?
• What is the need for Geoenvironmental
Engineering?
• Is there any special testing conducted?
• Why we need to focus on these testing?
• What is the need for Geoenvironmental
Engineering?
• Is there any special testing conducted?
• Why we need to focus on these testing?• Why we need to focus on these testing?
• What way it is related to sustainable?
• Why we need to focus on these testing?
• What way it is related to sustainable?
Questions to be answered?
• What is the need for Geoenvironmental
Engineering?
• Is there any special testing conducted?
• Why we need to focus on these testing?
• What is the need for Geoenvironmental
Engineering?
• Is there any special testing conducted?
• Why we need to focus on these testing?• Why we need to focus on these testing?
• What way it is related to sustainable?
• Why we need to focus on these testing?
• What way it is related to sustainable?
Starting Point
Sustainable Development - Geotechnics
Need for Geoenvironmental Engineering
IssuesIssues areare
• Ascertaining the quality of air, water, and land
resources;
• Transport, use, and disposal of hazardous wastes
IssuesIssues areare
• Ascertaining the quality of air, water, and land
resources;
• Transport, use, and disposal of hazardous wastes
• water and wastewater treatment, and reuse.
• Analysis and design of foundation systems, seepage
control, earth dams and water resource structures,
response of foundations and embankments to the
ENVIRONMENTAL ACTIVITIES
• water and wastewater treatment, and reuse.
• Analysis and design of foundation systems, seepage
control, earth dams and water resource structures,
response of foundations and embankments to the
ENVIRONMENTAL ACTIVITIES
Need for Geoenvironmental Engineering
• Assessment of pollutants being discharged on/in thesoil deposits (Disposal/Handling/storage)(Disposal/Handling/storage)
• Process by which the pollutants travel in geo-environment (Contaminant(Contaminant Transport)Transport)
• Protection of ground water aquifers from contamination
• Assessment of pollutants being discharged on/in thesoil deposits (Disposal/Handling/storage)(Disposal/Handling/storage)
• Process by which the pollutants travel in geo-environment (Contaminant(Contaminant Transport)Transport)
• Protection of ground water aquifers from contamination• Protection of ground water aquifers from contamination(Containment)(Containment)
• Methods of cleaning the contaminated sites(Remediation)(Remediation)
• Methods of creating “Value added” products (Recycling(Recycling&& Reuse)Reuse)
• Protection of ground water aquifers from contamination(Containment)(Containment)
• Methods of cleaning the contaminated sites(Remediation)(Remediation)
• Methods of creating “Value added” products (Recycling(Recycling&& Reuse)Reuse)
Questions to be answered?
• What is the need for Geoenvironmental
Engineering?
• Is there any special testing conducted?
• Why we need to focus on these testing?
• What is the need for Geoenvironmental
Engineering?
• Is there any special testing conducted?
• Why we need to focus on these testing?• Why we need to focus on these testing?
• What way it is related to sustainable?
• Why we need to focus on these testing?
• What way it is related to sustainable?
Geoenvironmental Investigation
Investigation for geoenvironmental application will inevitably
require a thorough understanding of the:
� Composition and characteristics of substrate materials,
� Composition of wastes and issues arising from the handling of
the waste materials,
Investigation for geoenvironmental application will inevitably
require a thorough understanding of the:
� Composition and characteristics of substrate materials,
� Composition of wastes and issues arising from the handling of
the waste materials,the waste materials,
� Interaction mechanisms between the waste and substrate
materials,
� Basic principles of the treatment techniques, and
� Immediate and long term adverse health effects of the chosen
remedial measures.
the waste materials,
� Interaction mechanisms between the waste and substrate
materials,
� Basic principles of the treatment techniques, and
� Immediate and long term adverse health effects of the chosen
remedial measures.
Geotechnical and Geoenvironmental TestingGeotechnical and Geoenvironmental Testing
Soil Testing
Geotechnical Testing
Geoenvironmental TestingTesting
Classification
Test
Engineering Properties Test
Testing
Classical Methods Alternative (special) Methods
Geotechnical and Geoenvironmental TestingGeotechnical and Geoenvironmental Testing
Soil Testing
Present GeoenvironmentaPresent Scenario
Grain-size distribution
Soil Consistency (moisture content)
Atterberg Limits
Geoenvironmental Testing -Scenario
Specific surface
pH in pore fluid
Ion-exchange capacity
Thermal & Electrical properties
Granular soils or
Cohesionless soils
Cohesive
soils
200634.75
Grain size (mm)
BoulderClay Silt Sand Gravel Cobble
Fine Fine grain grain
soilssoilsCoarse grain
soils
pH or Hydrogen-ion Activity
The most important chemical property of soil is the hydrogen ion activity or pH.
The pH of soils is measured using a glass electrode pH meter following the standard procedures such as ASTM D 4972.
Test Procedure:
Generally, the testing procedures essentially involve mixing one part of soil
The most important chemical property of soil is the hydrogen ion activity or pH.
The pH of soils is measured using a glass electrode pH meter following the standard procedures such as ASTM D 4972.
Test Procedure:
Generally, the testing procedures essentially involve mixing one part of soil Generally, the testing procedures essentially involve mixing one part of soil with one part of distilled water in a beaker, stirring the suspension for thirty minutes, allowing the suspended clay to settle for one hour, immersing the glass electrode partly into the settled suspension, and measuring the pH.
The measured soil pH is influenced by
• the soil-to-water ratio (or dilution),
• the soluble salts, and
• CO2 in the air.
Generally, the testing procedures essentially involve mixing one part of soil with one part of distilled water in a beaker, stirring the suspension for thirty minutes, allowing the suspended clay to settle for one hour, immersing the glass electrode partly into the settled suspension, and measuring the pH.
The measured soil pH is influenced by
• the soil-to-water ratio (or dilution),
• the soluble salts, and
• CO2 in the air.
pH or Hydrogen-ion Activity
• The soil-to-water ratio ranges from 1:1 to 1:10, with 1:1
being the most commonly used.
• Highly plastic soils may require higher dilution to keep
soil particles in suspension.
• In general, the more dilute the soil suspension, the
• The soil-to-water ratio ranges from 1:1 to 1:10, with 1:1
being the most commonly used.
• Highly plastic soils may require higher dilution to keep
soil particles in suspension.
• In general, the more dilute the soil suspension, the• In general, the more dilute the soil suspension, the
higher the soil pH value found, whether the soil is acidic
or alkaline.
• The rise in soil pH with dilution may be on the order of
0.2 to 0.5 pH units, but can be 1 or more pH units in
certain neutral and alkaline soils.
• In general, the more dilute the soil suspension, the
higher the soil pH value found, whether the soil is acidic
or alkaline.
• The rise in soil pH with dilution may be on the order of
0.2 to 0.5 pH units, but can be 1 or more pH units in
certain neutral and alkaline soils.
pH or Hydrogen-ion Activity
• The pH of a soil suspension may decrease due to
the solubilization of salts, if present, in the soil.
• To mask the variability of salt content of soils, the
soil pH is measured using one part soil and 2 parts
• The pH of a soil suspension may decrease due to
the solubilization of salts, if present, in the soil.
• To mask the variability of salt content of soils, the
soil pH is measured using one part soil and 2 partssoil pH is measured using one part soil and 2 parts
0.01M CaCl2 solution, prepared with distilled water.
• This soil suspension promotes accurate soil pH and
is independent of soil-to-water ratio (dilution), as
well as dissolved salts.
soil pH is measured using one part soil and 2 parts
0.01M CaCl2 solution, prepared with distilled water.
• This soil suspension promotes accurate soil pH and
is independent of soil-to-water ratio (dilution), as
well as dissolved salts.
pH or Hydrogen-ion Activity
• pH is the chemical property that effects various chemical processes such as adsorption / desorption, precipitation/dissolution, and oxidation/reduction.
• These processes, in turn, control the fate and
• pH is the chemical property that effects various chemical processes such as adsorption / desorption, precipitation/dissolution, and oxidation/reduction.
• These processes, in turn, control the fate and • These processes, in turn, control the fate and transport of the chemicals in soils.
• Therefore, determination of pH value is very important in understanding various geochemical reactions.
• These processes, in turn, control the fate and transport of the chemicals in soils.
• Therefore, determination of pH value is very important in understanding various geochemical reactions.
Surface Charge and Point of Zero Charge (PZC)
• Coarse-grained soils such as gravel, sand and silt are chemically inert.
• Clay mineral surfaces generally carry electronegative charges.
• Coarse-grained soils such as gravel, sand and silt are chemically inert.
• Clay mineral surfaces generally carry electronegative charges. electronegative charges.
• The negative charges on clay surfaces are a result of two occurrences:
– isomorphous substitution, and
– the disassociation of exposed hydroxyl groups.
electronegative charges.
• The negative charges on clay surfaces are a result of two occurrences:
– isomorphous substitution, and
– the disassociation of exposed hydroxyl groups.
Surface Charge and Point of Zero Charge (PZC)
• Isomorphous substitution is the substitution of
atoms for other atoms without affecting the crystal
structure.
• This substitution is possible in both the silica
tetrahedra and the aluminum octahedra of the clay
• Isomorphous substitution is the substitution of
atoms for other atoms without affecting the crystal
structure.
• This substitution is possible in both the silica
tetrahedra and the aluminum octahedra of the claytetrahedra and the aluminum octahedra of the clay
mineral.
• Isomorphous substitution will occur only between
atoms of almost equal size, and when the difference
in valance does not exceed one unit.
tetrahedra and the aluminum octahedra of the clay
mineral.
• Isomorphous substitution will occur only between
atoms of almost equal size, and when the difference
in valance does not exceed one unit.
Surface Charge and Point of Zero Charge (PZC)
• For example, in the absence of isomorphous
substitution, kaolinite is electrically
balanced.
• However, an isomorphic replacement of one
octahedral Al+3 by Mg+2 yields one
• For example, in the absence of isomorphous
substitution, kaolinite is electrically
balanced.
• However, an isomorphic replacement of one
octahedral Al+3 by Mg+2 yields oneoctahedral Al+3 by Mg+2 yields one
unbalanced negative charge in the crystal.
• This is because Mg+2 is divalent and
contributes only two positive charges to the
neutralization of the crystal.
octahedral Al+3 by Mg+2 yields one
unbalanced negative charge in the crystal.
• This is because Mg+2 is divalent and
contributes only two positive charges to the
neutralization of the crystal.
Surface Charge and Point of Zero Charge (PZC)
• A similar substitution can also occur in a Si
tetrahedron, where Si+4 can be replaced by Al+3,
resulting in one negative charge that has not
been neutralized.
These types of charges are called permanent
• A similar substitution can also occur in a Si
tetrahedron, where Si+4 can be replaced by Al+3,
resulting in one negative charge that has not
been neutralized.
These types of charges are called permanent• These types of charges are called permanent
negative charges, and are independent of pH.
• The negative charge on a clay surface is also
due to the presence of exposed hydroxyls
(OH) on the surface of Al octahedral sheets.
• These types of charges are called permanent
negative charges, and are independent of pH.
• The negative charge on a clay surface is also
due to the presence of exposed hydroxyls
(OH) on the surface of Al octahedral sheets.
Surface Charge and Point of Zero Charge (PZC)
• This dissociation of the H+ leaves one negativecharge, in the octahedron, which is not neutralized.
• Such a dissociation reaction is dependent upon pH.
• The dissociation reaction occurs at high pH, anddecreases at low pH.
• This dissociation of the H+ leaves one negativecharge, in the octahedron, which is not neutralized.
• Such a dissociation reaction is dependent upon pH.
• The dissociation reaction occurs at high pH, anddecreases at low pH.decreases at low pH.
• Therefore, the magnitude of negative charge alsoincreases and decreases with change in pH.
• This type of negative charge is called pH-dependentcharge or variable charge.
decreases at low pH.
• Therefore, the magnitude of negative charge alsoincreases and decreases with change in pH.
• This type of negative charge is called pH-dependentcharge or variable charge.
Surface Charge and Point of Zero Charge (PZC)
• The surface charge may have major implications onthe distribution of ionic contaminants in soils.
• If the surface charge is negative, cationic metalssuch as lead (Pb+2) will be bonded to the soilsurfaces.
• The surface charge may have major implications onthe distribution of ionic contaminants in soils.
• If the surface charge is negative, cationic metalssuch as lead (Pb+2) will be bonded to the soilsurfaces.surfaces.
• However, if the surface charge is positive, anionicmetal complexes, such as chromate, (CrO4
-2) will bebonded to the soil surfaces.
• The PZC is useful in determining the pH range inwhich soil surfaces are positively charged ornegatively charged.
surfaces.
• However, if the surface charge is positive, anionicmetal complexes, such as chromate, (CrO4
-2) will bebonded to the soil surfaces.
• The PZC is useful in determining the pH range inwhich soil surfaces are positively charged ornegatively charged.
Cation Exchange Capacity (CEC)
• When the surface charge of a soil is negative,the negative charges are balanced by cationssuch as Na+, Ca+2, Mg+2 and others, which formthe diffuse double layer.
• These cations can be replaced rather easily by
• When the surface charge of a soil is negative,the negative charges are balanced by cationssuch as Na+, Ca+2, Mg+2 and others, which formthe diffuse double layer.
• These cations can be replaced rather easily by• These cations can be replaced rather easily byone another; therefore, they are calledexchangeable cations.
• The sum of exchangeable cations is called thecation exchange capacity (CEC).
• These cations can be replaced rather easily byone another; therefore, they are calledexchangeable cations.
• The sum of exchangeable cations is called thecation exchange capacity (CEC).
Cation Exchange Capacity (CEC)
• CEC is expressed as milliequivalent per 100 grams of dry soil and is denoted as meq/100g.
• the milliequivalent of an ion is the atomic weight of the ion in milligrams divided by the valence of the ion.
• CEC is expressed as milliequivalent per 100 grams of dry soil and is denoted as meq/100g.
• the milliequivalent of an ion is the atomic weight of the ion in milligrams divided by the valence of the ion. valence of the ion.
• For example, 1 meq of H+ is equal to 1 mg of H; 1 meq of Na+ is equal to 23 mg of Na; 1 meqof K+ is equal to 39 mg of K, and 1 meq of Ca+2
is equal to 40/2 = 20 mg of Ca.
valence of the ion.
• For example, 1 meq of H+ is equal to 1 mg of H; 1 meq of Na+ is equal to 23 mg of Na; 1 meqof K+ is equal to 39 mg of K, and 1 meq of Ca+2
is equal to 40/2 = 20 mg of Ca.
Cation Exchange Capacity (CEC)
• Many methods have been reported for the determination of CEC of soils (ASA, 1965).
• These methods essentially involve replacing exchangeable cations by saturating the soil with a selected cation.
• Many methods have been reported for the determination of CEC of soils (ASA, 1965).
• These methods essentially involve replacing exchangeable cations by saturating the soil with a selected cation. with a selected cation.
• The saturating cation may be generated using one of three reagents: 1N ammonium acetate (pH=7.0), 1N sodium acetate (pH=8.2), or 0.5N barium chloride plus 0.2N triethanolaminesolution (pH=8.2).
with a selected cation.
• The saturating cation may be generated using one of three reagents: 1N ammonium acetate (pH=7.0), 1N sodium acetate (pH=8.2), or 0.5N barium chloride plus 0.2N triethanolaminesolution (pH=8.2).
Cation Exchange Capacity (CEC)
• The first two reagents are used for
calcareous and noncalcareous soils and the
third reagent is used for soils where it is
desired to determine both exchange
• The first two reagents are used for
calcareous and noncalcareous soils and the
third reagent is used for soils where it is
desired to determine both exchangedesired to determine both exchange
capacity and the amounts of exchangeable
hydrogen.
desired to determine both exchange
capacity and the amounts of exchangeable
hydrogen.
Cation Exchange Capacity (CEC)
• The test procedure essentially consists of mixingknown amounts of dry soil with the reagentsolution, shaking thoroughly, and filtering orcentrifuging to separate the supernatant.
• This process is repeated three to four times toensure all of the exchangeable cations are replaced
• The test procedure essentially consists of mixingknown amounts of dry soil with the reagentsolution, shaking thoroughly, and filtering orcentrifuging to separate the supernatant.
• This process is repeated three to four times toensure all of the exchangeable cations are replacedensure all of the exchangeable cations are replacedby the cation in the selected reagent (e.g.ammonium or Na).
• Finally, the amount of adsorbed reagent cations inthe soil (ammonium or Na) is equal to the CEC, andis extracted and determined by standard methods.
ensure all of the exchangeable cations are replacedby the cation in the selected reagent (e.g.ammonium or Na).
• Finally, the amount of adsorbed reagent cations inthe soil (ammonium or Na) is equal to the CEC, andis extracted and determined by standard methods.
Cation Exchange Capacity (CEC)
• The CEC differs from soil to soil depending on– clay content,
– clay types, and
– organic content.
• CEC is higher in soils that contain high clay content andhigh organic content.
• The CEC differs from soil to soil depending on– clay content,
– clay types, and
– organic content.
• CEC is higher in soils that contain high clay content andhigh organic content.high organic content.
• Adsorption of contaminants in soils depends on soil CECvalues.
• The higher the CEC, the higher the adsorption ofcationic contaminants on the soil surfaces, increasingthe difficulty of removal during remediation processimplementation.
high organic content.
• Adsorption of contaminants in soils depends on soil CECvalues.
• The higher the CEC, the higher the adsorption ofcationic contaminants on the soil surfaces, increasingthe difficulty of removal during remediation processimplementation.
Cation Exchange Capacity (CEC)
Clay Minerals/Soil Types CEC (meq/100g)
Chlorite 10-40
Illite 10-40
Kaolinite 3-15
Montmorillonite 80-150
Oxides and Oxyhydroxides 2-6
Vermiculite 100-150Vermiculite 100-150
Soil Organic Matter >200
Sand 2-7
Sandy Loam 2-18
Loam 8-22
Silt Loam 9-27
Clay Loam 4-32
Clay 5-60
Anion Exchange Capacity (AEC)
• The anion exchange capacity (AEC) is the capacity of soil to adsorb and exchange anions.
• The soil must be positively charged to adsorb negatively charged ions.
• Positive charges in soils occur only in low pH or acidic conditions when the soil pH is below the PZC
• The anion exchange capacity (AEC) is the capacity of soil to adsorb and exchange anions.
• The soil must be positively charged to adsorb negatively charged ions.
• Positive charges in soils occur only in low pH or acidic conditions when the soil pH is below the PZC
• Positive charges in soils occur only in low pH or acidic conditions when the soil pH is below the PZC of the soil.
• A positive charge can also develop from of broken bonds on broken surfaces of clay minerals.
• In general, the positive charge, hence the anion exchange capacity of soils, is considered smaller than the CEC.
• Positive charges in soils occur only in low pH or acidic conditions when the soil pH is below the PZC of the soil.
• A positive charge can also develop from of broken bonds on broken surfaces of clay minerals.
• In general, the positive charge, hence the anion exchange capacity of soils, is considered smaller than the CEC.
Anion Exchange Capacity (AEC)
• The procedure used to determine AEC of a soil is similar to the CEC procedure, except that different reagent solutions are used to replace all of the exchangeable anions in the soil.
• Most commonly used, and preferred, reagents
• The procedure used to determine AEC of a soil is similar to the CEC procedure, except that different reagent solutions are used to replace all of the exchangeable anions in the soil.
• Most commonly used, and preferred, reagents • Most commonly used, and preferred, reagents contain Cl- due to its nonspecific adsorption characteristics.
• AEC values commonly range from 1 to10 mmol/kg, but can be as high as 1 mol/kg in soils with high organic matter and metal oxide contents.
• Most commonly used, and preferred, reagents contain Cl- due to its nonspecific adsorption characteristics.
• AEC values commonly range from 1 to10 mmol/kg, but can be as high as 1 mol/kg in soils with high organic matter and metal oxide contents.
Anion Exchange Capacity (AEC)
• Similar to CEC, adsorption of anionic
contaminants on soil surfaces depends on
the AEC. Higher AEC results in higher
adsorption of anionic contaminants and
• Similar to CEC, adsorption of anionic
contaminants on soil surfaces depends on
the AEC. Higher AEC results in higher
adsorption of anionic contaminants and adsorption of anionic contaminants and
may be an important consideration in the
design of remedial processes.
adsorption of anionic contaminants and
may be an important consideration in the
design of remedial processes.
Specific Surface
• The specific surface of minerals is defined asthe ratio of surface area to either volume ormass.
• Specific surface is determined by the ethyleneglycol, glycerol or ethylene glycol monoethyl
• The specific surface of minerals is defined asthe ratio of surface area to either volume ormass.
• Specific surface is determined by the ethyleneglycol, glycerol or ethylene glycol monoethylglycol, glycerol or ethylene glycol monoethylether (EGME) adsorption procedure.
• These amounts provide a quantitativedetermination of clay minerals and anestimate of specific surface area.
glycol, glycerol or ethylene glycol monoethylether (EGME) adsorption procedure.
• These amounts provide a quantitativedetermination of clay minerals and anestimate of specific surface area.
Specific Surface
• Particles smaller than 1 µm posses significant
surface area and the surface properties of such
particles will have significant consequences.
• For instance, larger surface area may result in
• Particles smaller than 1 µm posses significant
surface area and the surface properties of such
particles will have significant consequences.
• For instance, larger surface area may result in• For instance, larger surface area may result in
higher unbalanced surface charge, which in turn
may cause greater sorption of contaminants.
• Such circumstances influence remedial processes
and waste leaching conditions.
• For instance, larger surface area may result in
higher unbalanced surface charge, which in turn
may cause greater sorption of contaminants.
• Such circumstances influence remedial processes
and waste leaching conditions.
Specific Surface
Mineral Specific Surface (m2/g)
Quartz 0.14
Gibbsite 120
Hematite 1.8Hematite 1.8
Kaolinite 10-38
Illite 65-100
Montmorillonite 600-800
Case Study – Construction of Landfill
Importance of engineering properties of wasteImportance of engineering properties of waste
Ohio Landfill slope failure
10/22/2011 44
10/22/2011 46
Case Study – Construction of Landfill
The primary concern in the design and operation of thisfacility are:
• The liner system must restrict the escape of leachate to
acceptable limits through a combination of an effective
leachate collection and removal system.
The primary concern in the design and operation of thisfacility are:
• The liner system must restrict the escape of leachate to
acceptable limits through a combination of an effective
leachate collection and removal system.leachate collection and removal system.
• To assure proper performance over the long life of a waste
landfill requires that there be chemical, biological, and
mechanical compatibility between several components.
• The leachate collection and containment function requires
application of hydraulic conductivity, seepage and drainage
principles.
leachate collection and removal system.
• To assure proper performance over the long life of a waste
landfill requires that there be chemical, biological, and
mechanical compatibility between several components.
• The leachate collection and containment function requires
application of hydraulic conductivity, seepage and drainage
principles.
Case Study – Construction of Landfill
• Liner system used for the containment and removal of
landfill leachate may contain geosynthetics interfaces with
vey low strengths. e.g., friction angle of 8 degrees or less.
• Compacted clay (or compacted amended soil) layer has a
coefficient of permeability of 10-7 cm/sec (10-9 m/sec) or
less; is devoid of clods and shrinkage cracks; and achieves
• Liner system used for the containment and removal of
landfill leachate may contain geosynthetics interfaces with
vey low strengths. e.g., friction angle of 8 degrees or less.
• Compacted clay (or compacted amended soil) layer has a
coefficient of permeability of 10-7 cm/sec (10-9 m/sec) or
less; is devoid of clods and shrinkage cracks; and achievesless; is devoid of clods and shrinkage cracks; and achieves
the desired strength.
• the geomembranes is laid in intimate contact with the
compacted clay/compacted amended soil layer; is properly
joined/welded at the seams; and is not puncture by
construction vehicles/tools
less; is devoid of clods and shrinkage cracks; and achieves
the desired strength.
• the geomembranes is laid in intimate contact with the
compacted clay/compacted amended soil layer; is properly
joined/welded at the seams; and is not puncture by
construction vehicles/tools
Case Study – Construction of Landfill
• The leachate collection layer has a coefficient
of permeability of 10-2 cm/sec (10-4 m/sec) or
more and does not become clogged by
• The leachate collection layer has a coefficient
of permeability of 10-2 cm/sec (10-4 m/sec) or
more and does not become clogged by
intermixing or migration of fine particles.
• Compacted clay and the interface between a
HDPE geomembrane may have a very low
shearing resistance.
intermixing or migration of fine particles.
• Compacted clay and the interface between a
HDPE geomembrane may have a very low
shearing resistance.
Case Study – Construction of Landfill
Case Study – Construction of Landfill
Case Study – Construction of Landfill
Case Study – Construction of Landfill
Case Study – Construction of Landfill
Case Study – Construction of Landfill
Case Study – Construction of Landfill
Case Study – Construction of Landfill
Case Study – Construction of Landfill
Case Study – Construction of Landfill
Case Study – Construction of Landfill
• Testing of proposed clay liner material for
compliance with the specified requirements.
Should satisfy liner requirements– Hydraulic conductivity < 10-7 cm/s
– Particle size
• Testing of proposed clay liner material for
compliance with the specified requirements.
Should satisfy liner requirements– Hydraulic conductivity < 10-7 cm/s