CE 100: Introduction to Civil and Environmental Engineering
Geotechnical Engineering
Nov 3rd 2013
Lecture 7
What is Geotechnical Engineering?
Geotechnical engineering involves investigation and engineering evaluation of
-materials, -their systems-structural foundations and -other civil engineering works.
It also involves applications of the -principles of the soil mechanics - construction techniques and -performance evaluation of civil engineering work
influenced by earth materials.
It requires comprehensive understanding of the elements of geologic environment.
Which type of information is needed in Geotechnical Engineering?
• Nature and composition of Soil and rock. • Ground water condition • Soil stresses:
– stress history, over-consolidation, lateral stresses. • Confined compression of soils. • Soil suction, collapse and swelling. • Soil strength and deformability:
GEOTECHNICAL APPLICATIONSFoundations
Retaining walls
Earthern Dams
Concrete Dams
Geomembrane/geosynthetics
Trenchless technology
GEOTECHNICAL APPLICATIONS
Foundation Engineering– Foundation engineering is an art ofselecting, designing and constructing the elementsthat transfer the weight of structure to theunderlying soil or rock.
– Before designing a foundation, the engineer must have a reasonably accurate conception of
the physical properties and
the arrangement of the underlying materials.
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Retaining Walls~ for retaining soils from spreading laterally
Road
Train
retaining wall
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Earth Dams~ for impounding water
soil
reservoirclay core shell
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Concrete Dams
reservoir
soil
concrete dam
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Concrete Dams
Three Gorges Dam, Hong Kong
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Sheet Piles~ resist lateral earth pressures
~ used in excavations, waterfront structures, ..
~ in temporary works
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Geofabrics~ used for reinforcement, separation, filtration and drainage in roads, retaining walls, embankments…
Geofabrics used on Pacific Highway
Geosynthetics/Geomembrane
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Geosynthetics/Geomembrane
Waste Disposal in Landfills
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Reinforced Earth Walls~ using geofabrics to strengthen the soil
Trenchless Technology
http://nastt-bc.org/content/listing-trenchless-technology-pictures