Environmental Engineering Reference
In-Depth Information
TABLE 4.5
Surveying Methods Summarized a
Method
Range
Accuracy
Advantages
Limitations
Reliability
and
Precautions
Chaining
Variable
Simple, direct
Requires
Excellent
1
00
1
000
50
10,
to
observation
clear,
relatively flat
Ordinary (third
surface
order) survey
between
points and
1
000
1
,000
20,
200
to
stable
reference
Precise (first-order)
monuments
survey
Inexpensive
Corrections
for
temperature
and slope
should be
applied and
a standard
tension used
1
000
1
,000
50,
300
to
Electronic
50 to
Precise, long
Accuracy
Good
distance
10,000 ft
range, fast
influenced
measuring
of distance
by atmospheric
conditions
Usable over
Accuracy at
rough terrain
short ranges
(under 100-
300 ft) is
limited
Optical leveling
Ordinary-second
0.01 to
0.02 ft
Simple, fast
Limited
Excellent
and third order
(particularly
precision.
with self-
Requires
leveling
good bench
instruments)
mark nearby
Precise parallel-
0.002 to
0.004 ft
More precise
Requires
Excellent
plate micrometer
good bench
attachment,
mark and
special rod, first-
reference
order technique
points, and
careful
adherence to
standard
procedures
Offsets from a
baseline
Theodolite and
0 to 5 ft
0.002 to
0.005 ft
Simple direct
Requires
Excellent
scale
off-
observation
baseline
baseline
unaffected
by
movements
and good
monuments.
( Continued )
 
 
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