Design with Geomembranes Notes | EduRev

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Objectives_template
 Module 10:Design methods of Geogrids, Geonets and geomembranes 
 Lecture 31:Design with Geomembranes 
 
The Lecture Contains: 
Applicatins of Geomembrane
 
 
 
 
 
 
 
 
 
 
file:///D|/Dr.patra/ground_improvement_techniques/lecture31/31_1.htm [10/12/2011 11:59:09 AM]
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Objectives_template
 Module 10:Design methods of Geogrids, Geonets and geomembranes 
 Lecture 31:Design with Geomembranes 
 
The Lecture Contains: 
Applicatins of Geomembrane
 
 
 
 
 
 
 
 
 
 
file:///D|/Dr.patra/ground_improvement_techniques/lecture31/31_1.htm [10/12/2011 11:59:09 AM]
Objectives_template
 Module 10:Design methods of Geogrids, Geonets and geomembranes 
 Lecture 31:Design with Geomembranes 
 
Geomembrane
Typical cross sections
 
 
 
 
 
 
 
 
 
 
 
file:///D|/Dr.patra/ground_improvement_techniques/lecture31/31_2.htm (1 of 2) [10/12/2011 11:59:09 AM]
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Objectives_template
 Module 10:Design methods of Geogrids, Geonets and geomembranes 
 Lecture 31:Design with Geomembranes 
 
The Lecture Contains: 
Applicatins of Geomembrane
 
 
 
 
 
 
 
 
 
 
file:///D|/Dr.patra/ground_improvement_techniques/lecture31/31_1.htm [10/12/2011 11:59:09 AM]
Objectives_template
 Module 10:Design methods of Geogrids, Geonets and geomembranes 
 Lecture 31:Design with Geomembranes 
 
Geomembrane
Typical cross sections
 
 
 
 
 
 
 
 
 
 
 
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Objectives_template
Figure 31.1
 
 
 
 
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Objectives_template
 Module 10:Design methods of Geogrids, Geonets and geomembranes 
 Lecture 31:Design with Geomembranes 
 
The Lecture Contains: 
Applicatins of Geomembrane
 
 
 
 
 
 
 
 
 
 
file:///D|/Dr.patra/ground_improvement_techniques/lecture31/31_1.htm [10/12/2011 11:59:09 AM]
Objectives_template
 Module 10:Design methods of Geogrids, Geonets and geomembranes 
 Lecture 31:Design with Geomembranes 
 
Geomembrane
Typical cross sections
 
 
 
 
 
 
 
 
 
 
 
file:///D|/Dr.patra/ground_improvement_techniques/lecture31/31_2.htm (1 of 2) [10/12/2011 11:59:09 AM]
Objectives_template
Figure 31.1
 
 
 
 
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Objectives_template
 Module 10:Design methods of Geogrids, Geonets and geomembranes 
 Lecture 31:Design with Geomembranes 
 
Geomembrane
Geomembrane Material Selection:
1.  For portable water storage, service lifetime is approximately 20 years.
2.  For storage of liquids containing acids, bases, heavy metals, salts chemical resistance should be 
taken into consideration.
3.  For storage of liquids, that are combination of chemicals, the most aggressive of individual liquids 
should be used for selection process. This assumes that there are no synergistic effects occurring 
within the different liquids.
4.  For storage of liquids that are an unidentifiable or of as unknown variety extreme conservatism 
must be used. 
Thickness Considerations: Deformation is induced by one of the settlement Mechanism.
 
Figure 31.2
= Settlement moblising in stress.
F = force mobilized in the linear = 
  = Linear allowable stress p = applied pressure from reservoir.
t = linear thickness
 
 
 
 
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Objectives_template
 Module 10:Design methods of Geogrids, Geonets and geomembranes 
 Lecture 31:Design with Geomembranes 
 
The Lecture Contains: 
Applicatins of Geomembrane
 
 
 
 
 
 
 
 
 
 
file:///D|/Dr.patra/ground_improvement_techniques/lecture31/31_1.htm [10/12/2011 11:59:09 AM]
Objectives_template
 Module 10:Design methods of Geogrids, Geonets and geomembranes 
 Lecture 31:Design with Geomembranes 
 
Geomembrane
Typical cross sections
 
 
 
 
 
 
 
 
 
 
 
file:///D|/Dr.patra/ground_improvement_techniques/lecture31/31_2.htm (1 of 2) [10/12/2011 11:59:09 AM]
Objectives_template
Figure 31.1
 
 
 
 
file:///D|/Dr.patra/ground_improvement_techniques/lecture31/31_2.htm (2 of 2) [10/12/2011 11:59:09 AM]
Objectives_template
 Module 10:Design methods of Geogrids, Geonets and geomembranes 
 Lecture 31:Design with Geomembranes 
 
Geomembrane
Geomembrane Material Selection:
1.  For portable water storage, service lifetime is approximately 20 years.
2.  For storage of liquids containing acids, bases, heavy metals, salts chemical resistance should be 
taken into consideration.
3.  For storage of liquids, that are combination of chemicals, the most aggressive of individual liquids 
should be used for selection process. This assumes that there are no synergistic effects occurring 
within the different liquids.
4.  For storage of liquids that are an unidentifiable or of as unknown variety extreme conservatism 
must be used. 
Thickness Considerations: Deformation is induced by one of the settlement Mechanism.
 
Figure 31.2
= Settlement moblising in stress.
F = force mobilized in the linear = 
  = Linear allowable stress p = applied pressure from reservoir.
t = linear thickness
 
 
 
 
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Objectives_template
 = shear force on top of linear
 = shear force below linear
= angle of shearing resistance between liner and adjacent material.
 = distance of mobilized liner material.
General Ranges 
(determined from Laboratory test)
 For liquid containment
       For landfill containment. 
Example:31.1  
Determine the thickness of geomembrane to be used in the containment of a 30ft deep water 
reservoir where the potential settlement over a backfilled collector pipe could amount to 6in. 
The linear material will be textured PVC of 120,000  allowable stress. There is only a  
thin soil cover over the linear and a silt film woven geotextile is to be placed beneath it.  
The estimated mobilized distance for linear deformation is 2.0in.
 
 
 
 
 
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