Liquid limit is the water content where the soil starts to behave as a liquid. Liquid limit is measured by placing a clay sample in a standard cup and making a separation (groove) using a spatula. The cup is dropped till the separation vanishes. The water content of the soil is obtained from this sample.

2. "...to design and construct public works..."
Civil Engineering
Practice of improving and maintaining the
built and natural environment to enhance
the quality of life for present and the
generations to follow
Transformation

3. Role of Civil Engineers
“Designers and Builders of
The Quality of Life…….”
Creators of the Civilised Society Environment
Providing solutions to the needs of a developing global
population
Performers (on a world stage) as strategic thinkers and
global managers
Pillars of local Economies
Creating and maintaining complex infrastructure in
wealth creation

4. Rock Mechanics
Foundations Retaining Structures Seepage/Slopes/Dams
Soil Mechanics
Geomechanics Environment
Geotechnical Engineering
Challenge
Effect is more
pronounced

5. Genesis
Population Explosion
Industrialization
Sluggish and “Don’t bother approach”
Ignorance
Human Greed
Is a Philosophy put in practice to deal with
under-ground “environment” & Problems associated with it
Combination/Blend of
Geotechnical Engg. and Environmental Engg.

6. Average water table
Waste Disposal Strategies
Above ground storage
No protection Protected by
geologic materials

7. wet period
average
dry period
Backfill
Shallow trench burial
Engineered
Backfill geological materials.

8. Deep Disposal
with backfill Protected by
high-
retardation geologic
material
Average water table
Backfill
Waste
Large boreholes 10 to 20 meters deep
Protective Geologic
material
Backfill
material
Waste
deposits
Unfrctured
clayey

9. Issues are
 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
Man made
Natural earthquakes/(& to some extent other natural calamities).
industrialization/population explosion

10. Protection of ground water aquifers from contamination
(Containment)
Assessment of pollutants being discharged on/in the soil deposits
(Disposal/Handling/storage)
Process by which the pollutants travel in geo-environment
(Contaminant Transport)
Methods of cleaning the contaminated sites
(Remediation)
Methods of creating “Value added” products
(Recycling & Reuse)

11.  Hazardous wastes
 Physical, Chemical, Mineralogical, Electrical and Thermal
characterization
 Geoenvironmental hazards:
Natural and man made
Recycle and Reuse of Industrial waste(s)
 Role of Geotechnical engineering in environmental protection
 Surface and subsurface contamination
 Characterization of contaminated ground
 Geoenvironmental site investigation
 Site assessment technologies

12. Soil-Water-Environment Interaction
The Natural
Environment
Geomicrobiosphere
Man Made
Environment
The Particle Energy Field
Theory
Environmental
Geotechnical
Problems
Understanding of Soil
response to
Environments
(Short & long-term)
Requires knowledge from other Disciplines
Bacteriology Biology Chemical Engg.
Climatology Geohydrology Geophysics
Geochemistry Hydrogeology Mechanics
Microgeology Physico-Chemistry Soil Science
Soil Engineering Toxicology

13. The Natural Environment
Atmosphere
Biosphere
Oxygen Cycle
Nitrogen Cycle
Carbon Cycle
Hydrosphere
Lithosphere
Geomicrobiosphere Ecosphere
The Cycle of Nature

14. Man-made Environment
Agricultural wastes
Human and Animal wastes
Industrial wastes
Mine wastes……Acid mine waste
(due to oxidation of Iron Sulphide (FeS2) or Pyrites to H2SO4)
Nuclear wastes
Construction Effects (Blasting/Dewatering/debris…)
Solid Liquid

15. Soil Response to Environments
Soil structures (on/in/with)
Pore fluid characteristics
Soil-heat
Soil-Chemical
Soil Bacteria
Soil-Root
Soil-Electrical
Soil-Liquid (water)

16. Basic concepts of Analysis
Most geotechnical projects occur in nature
Long-term phenomenon
Soil is more sensitive and susceptible to environment
than any other construction material
Loading may greatly affect soil properties but not the only
Parameter to be considered
Think of other factors:
Heat
Moisture (wet/Dry)
Pollution intrusion

17. Classical Soil Mechanics: Some flaws
Specific gravity and Atterberg limits are constant
Void ratio and porosity as indicators of soil deformation
Water in the soil mass is mainly gravity water
(need to consider Environmental water)
Flow through a soil mass is only due to hydrostatic potential
(need to consider thermal/electrical/magnetic/chemical effects)
Constitutive models are arbitrarily chosen.
Stress-strain relationship

18. Soil Classification: Controlling Parameters
Grain-size distribution
Soil Consistency (moisture content)
LL
PL
PI
Present
scenario
(Parameters)
Proposed
scenario
(Parameters)
% Passing #200 Sieve
Specific surface
pH in pore fluid
Ion-exchange capacity
Absorption & adsorption
Thermal properties (Conductivity, diffusivity, specific heat)
Dielectric constant (Electrical properties)

19. www.civil.iitb.ac.in/~dns
You are most welcome to Visit the laboratory

20.  There are 2 types of buildngs construction
1. Isolation Construction
2. Vibration Suspension Construction
Isolation consruction includes
equipments to absrob seismic energy from
foundation and prevent from shaking.
Vibration suspention utilizes suspention
equipment such as damper in wall to absorb
seismic energy and prevent from shaking.