Surveying Flashcards
BCF
Bank cubic feet
BCY
Bank cubic yards
BM
Benchmark
BS
Back sight
CCF
Compacted cubic feet
CCY
Compacted cubic yards
DD
Degree decimal
DMS
Degree minute second
FS
Foresight
HD
Horizontal distance
HI
Height of instrument
LCF
Loose cubic feet
LCY
Loose cubic yards
SPCS
State plane coordinate system
sta
Station
How many sig figs should be used in a problem?
The least amount of sig figs used in the problem
Horizontal control
Establishes horizontal control stations, or coordinates, for the duration of the project
Vertical control
Establishes vertical control stations, or elevations, for the duration of the project
Open traverse
Commonly used
Start and end on known locations
Open traverse
Uncommon
Starts on known location, ends on unknown locations
Angle closure
The avg error is equally distributed in a series of measurements and becomes the most probable interior angle measurement
Angle problem ex
N angles given
- (N-2)(180)= sum of interior angles
- Sum given angles
- Correct 2. To fit 1 (can be by subtracting or adding - will dictate next step)
- Add/subtract (3./N) to all given angles
Conversion from DMS to DD
Degree.Minute.Seconds
Minute/60 =m
Seconds/3600 =s
Degree+m+s
Law of sins
a/sin(A)=b/sin(B)=c/sin(C)
Law of cosines
a^2=b^2+c^2-2bcCos(A)
Bank
The volume of earth in its natural state
OTHER NAMES: bank-measure, in situ, in-place soil
Loose
The volume during transport
OTHER NAMES: loose-measure, fluffed, swell, bulk
Compacted
The volume after compaction
Swell
During excavation, the change in volume of earth from its natural state (or bank) to its loose state. Calculated as a percentage of bank volume
Shrinkage
During the placement and compaction of excavated soil, the decrease in volume from its natural state to its compacted state. Calculated as a percentage decrease from bank state
Average end area
Most widely used method to calculate volume of soil between stations in a roadway
Average end area eq
V = L(A1+A2)/2
Average end area Eq for PYRAMID
V = (L * A_base)/3
Area of land profile
A = 0.5[a(h0+h1)+b(h1+h2)+…]
DONT FORGET TO SUBTRACT THE GIVEN HEIGHT FROM THE INDIVIDUAL HEIGHTS
Prismoidal volume
V =(L(A1+4A_m+A2))/6
Prismoidal volume definition
Used when, in a series of three stations, the center of each area differs greatly from the outside stations ie when the ground surface is highly irregular
Latitude
Line that extends in north (+) or south (-) direction
Departure
Line that extends east (+) or west (-)
Land bearing
Horizontal angle
Azimuth
Vertical angle
Differential leveling
Used to determine the elevation difference between two points
Total station
Instrument used in surveying
Theodolite
Instrument for measuring both horizontal and vertical angles
Difference in elevation Δ
ΣBS - ΣTP
HI eq
= BS + BM
TP elevation eq
HI - FS
Percent grade
Angle = arctan(%slope/100)
Slope = 100tan(angle)
Change of measured length
C = α(ΔΤ)L
What do you use for finding third line formed by two lines
Law of Cosines
|BC| = (|AB|^2+|AC|^2-2|AB||AC|cos(BAC))^.5
Elev at BM1
BS - FS
Elev at Sta
Elev at BM1 +BS - FS
all things relèvent to Sta in question
Level line
Level line is a curved line
Horizontal line is a straight line
Rectangle based wedge volume
V = (hw/6)(a+b+c)
Used for measurement
Transit
Theodolite
When is earths real shape considered
Geodetic surveying
Percent grade
Tan(α)*100
Percent grade based on vertical and horizontal distance
g = V/H
Effect of earth curvature
Adds to reading. Subtract to fix
Effect of earths curve
0.0673D^2
Elevation
Elev at BM + ΣBS - ΣFS
Elev
Given HI V RR
Elev at BM + HI + V - RR
δV
General
Given error in angle and distance S
Sin(α) * δS + Scos(α)δα
