Geoscience Reference
In-Depth Information
Table 1.6
Geotechnical category (GC) of investigation.
Geotechnical
GC1
GC2
GC3
category
1. Nature and
Small & relatively
Conventional
Large or unusual
size of
simple - conventional
structures - no
structures.
construction
loadings.
abnormal loadings.
2. Surroundings
No risk of damage to
Risk of damage to
Extreme risk to
neighbouring buildings,
neighbouring
neighbouring
utilities, etc.
structures
structures.
3. Ground
Straightforward.
Routine procedures
Specialist testing.
conditions
Does not apply to
for field and
refuse, uncompacted
laboratory testing.
fill, loose or highly
compressible soils.
4. Ground water
No excavation below
Below water table.
Extremely
conditions
water table required.
Lasting damage
permeable
cannot be caused
layers.
without prior
warning
5. Seismicity
Non Seismic
Low seismicity
High Seismic areas.
6. Cost of project
$0.5 M (Aus - 2005)
$50 M (Aus - 2005)
<
>
7. SI Cost as % of
0.1%-0.5%
0.25%-1%
0.5%-2%
capital cost
8. Type of study
Qualitative investigation
Quantitative
Two stage investigation
may be adequate.
geotechnical studies.
required.
9. Minimum level
Graduate civil engineer
Experienced
Specialist geotechnical
of expertise
or engineering geologist
Geotechnical engineer/
Engineer with
under supervision by an
Engineering geologist.
relevant experience.
experienced geotechnical
Engineering geologist
specialist.
to work with specialist
geotechnical/tunnel/
geo-environmental
engineer/etc.
10. Examples
•
Sign supports
•
Industrial/
•
Dams
Walls
2 m
commercial
Tunnels
•
<
•
•
Single or 2-storey
some buildings
•
Ports
buildings
Roads
1km
Large bridges &
•
>
•
Domestic buildings;
Small/medium
buildings
•
•
light structures with
bridges
Heavy machinery
•
column loads up to
foundations
250 kN or walls
•
Offshore platforms
loaded to 100 kN/m
Deep basements
•
Some roads
•
•
Services searches are mandatory prior to ground truthing.
•
Further service location tests and/or isolations may be required on site. Typically
mandatory for any service within 3m of the test location.
•
Utility services plans both above and below the ground are required. For example,
an above ground electrical line may dictate either the proximity of the borehole,
Search WWH ::
Custom Search