CLT Preparation Workshops

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CLT Preparation Workshops
Survey - Instrument
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Acknowledgements

• Clackamas Community College in partnership with
  Oregon Landscape Contractors Association
• Certified Landscape Technician 2002-2003 State
  of Oregon Grant Project
• The State of Oregon administering the Department
  of Labor Workforce Investment Act Funds by acting
  through its Department of Community Colleges and
  Workforce Investment Council of Clackamas County

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Pre-Class Test

• Welcome.
• 1. Please complete the pre-class test.
• 2. When you finish your test, give it to the
  instructor.
• This pre-test will not be graded, it is to show
  how much you know about the subject before taking
  the class.
• Thank you!

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Learning Objectives

• Upon completion of this class, you will be able
  to
• Identify different types of survey equipment.
• Set up a tripod and mount an instrument on
  tripod.
• Hold and read survey rods.
• Calculate the slope between two points.
• Calculate the cut or fill required to make a
  specific slope for a given distance.
• Calculate a rod reading to obtain a specific
  elevation.
• Identify the common marks on grade stakes.

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Survey Instruments

• Types of instruments used to measure elevation
• Builders Level
• Transit
• Laser Level
• Tripod
• Rod

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Builders Level

• Description
• Application

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Transit

• Description
• Applications

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Transit
Can adjust vertically or locked at level.
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Laser Level

• Description
• Usage
• Do NOT look directly into the laser beam.

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Tripod

• Description
• Usage
• Setting up the tripod

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Mounting the Instrument on the Tripod

• 1. Remove the survey instrument from the box.
• Never lift the survey instrument by the
  telescope.
• 2. Screw the builders level footplate to the
  tripods baseplate.

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Leveling the Instrument

• 1. Adjust the four leveling screws.
• 2. Turn the telescope over.
• 3. Adjust the screws.

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Leveling the Instrument

• 4. Turn telescope over.
• 5. Adjust to level.
• 6. All four screws in firm contact with base.
• Caution Do not overtighten the screws.

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Leveling the Instrument

• 7. Check the level.
• 8. Adjust the leveling screws.
• 9. Adjust the bubble to the center of the level.

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Keeping the Instrument Level

• Do not bump or rest your hands on the tripod.
• Step back away from the tripod before moving
  around the tripod.
• Turn the level gently.

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Leveling the Laser

• 1. Mount the laser level.
• 2. Adjust 3 leveling screws to place bubble in
  the center circle.
• 3. Turn on the unit.

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Survey Rods

• Rods
• Surveyor's Rods
• Architectural Rods

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Holding the Rod Plumb
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Reading the Survey Rod

• Most rods read in
• feet
• 1/10 foot
• 1/100 foot

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Reading the Survey Rod

• Red Arrow reads
• 8.52 feet
• Blue Arrow reads
• 8.46 feet
• Yellow Arrow reads
• 8.39 feet
• Green Arrow reads
• 8.20 feet

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Read the Rod

• Red Arrow reads
• 3.14 feet
• Blue Arrow reads
• 3.00 feet
• Yellow Arrow reads
• 2.86 feet
• Green Arrow reads
• 2.59 feet

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Elevation Rod Readings

• Rod readings indicate the distance from a level
  plane.
• Higher elevations
• Lower elevations

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Grade Stakes

• Purpose.
• Stake markings
• a line and an F require fill up to the line.
• a line and a C require cutting the soil.

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Grade Stakes
F
C
2.3
Cut 2.3 feet below line
Fill up to line
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Practice

• 1. Go outside
• 2. Set up the levels
• 3. Measure elevation changes and distances
  between stakes.
• 4. Write down the rod readings and distances.
• When we come back in we will calculate the slope
  and gradient.

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Welcome Back
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Calculating Slope

• Slope is the change in elevation in relation to
  the horizontal distance.
• Slope may be listed as
• a ratio 41
• gradient 0.25
• percentage 25

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40
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Calculating the Slope Gradient

• 1. Measure the elevation difference between the
  two points (D) using a survey instrument.
• 2. Measure the horizontal length between the two
  points (L).
• 3. Divide the vertical difference (D) by the
  horizontal length (L).

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Calculating the Percent Slope

• 1. Determine the percent slope, multiply the
  slope gradient by 100.
• 2. Determine the gradient from percent slope.
• A gradient of 0.12 equals 12 slope
• A 4 slope equals a gradient of 0.04
• We often talk about percent slope but use the
  gradient for calculations.

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Calculating the Percent Slope
L
D
DL
Slope Gradient
DL
Units must beconsistent
Slope
X 100
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Calculating the Percent Slope
Calculating the percent slope between two points

• Slope Gradient D ? L
• Convert to Slope (D ? L) x 100

Units must beconsistent
L
D
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Calculating the Gradient Slope

• Formula G D/L
• 1. Take the measurements from outside.
• 2. Subtract the smaller rod reading from the
  larger rod reading to find the elevation
  difference D.
• 3. Divide D by the length between the points
  surveyed.
• 4. Multiply G x 100 for Percent Slope

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Practice

• Point A rod reading is 6.8, point B rod reading
  is 9.2. The length between point A B is 40.
• Determine which point is higher in elevation.
• Point A is higher.
• The lower the rod reading, the higher the
  elevation.

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Practice

• Point A rod reading is 6.8, point B rod reading
  is 9.2. The length between point A B is 40.
• Determine the slope gradient.
• G D/L
• G (9.2-6.8)/40
• G 2.4/40
• G 0.06

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Calculating Gradient

• G D/L Gradient Difference/Length
• L D/G Length Difference/Gradient
• D G x L Difference Gradient x Length

L
D
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Calculating Elevation Difference

• To calculate the elevation difference for slope
  of known length, use the formula
• D G x L
• 20 length at a 4 slope
• D 0.04 x 20 0.08 elevation difference

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Calculating Elevation Change
Calculating elevation change for an incline.
D Gradient x L
L
D
100.0 ft
Units must beconsistent
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Calculating Elevation Change
Calculating elevation change for a decline
D Gradient x L
Units must beconsistent
L
100.0 ft
D
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Calculating the Elevation Change

• If the slope is lower at point B, subtract the
  Elevation Change from point A.
• If the slope is higher at point B, add the
  Elevation Change to point A.
• A Elevation Change Elevation of B
• A Elevation Change Elevation of B

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Rod Reading for Elevation Changes

• If the slope is going down, take the rod reading
  of point A and add the elevation change.
• If the slope is going up, take the rod reading of
  point A and subtract the elevation change.
• This will give the rod reading at point B for the
  desired elevation.

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Practice

• Point A rod reading is 6.8, point B rod reading
  is 9.2. The length between point A B is 40.
• Determine the rod reading for point B after a 4
  slope is established.
• DG x L D 0.04 x 40 D1.6
• Point A D Rod reading
• 6.8 1.6 8.4 Rod reading after grading

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Cut or Fill Amounts

• Percent Slope and Gradient are always positive
  numbers so they do not indicate cut or fill.
• Look at the existing rod reading and compare to
  the calculated rod reading after grading.
  Compare Point A B to see the direction of
  slope.
• Draw a picture.

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Cut or Fill?

• Draw a picture with the rod readings to
  determine whether to cut or fill.
• Remember lower rod readings are higher
  elevations.
• In this case we fill.

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Practice What Youve Learned

• Use the remaining time in class to begin working
  on some of the practice problems in your handout.
• Every few days review your notes and re-do the
  practice problems to remember these concepts.

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What have you learned today?

• Before you leave today
• Complete the post-class test to help us determine
  how effective this class has been.
• Fill out the evaluation form.
• Thank you and good luck on the CLT test!