Carry out leveling operations (CPCCCA3023A)
Assessment task 1
- Review the plan below, then complete the table.
What is the lowest part of the block? : South East Corner
What is the highest part of the block? : North West Corner
- What is the biggest danger of using a laser level? What safety precaution should be followed to minimise this danger?
Eye
A safety glass or specialized goggles must be worn while working with a laser level. One should try best way possible not to directly look into the beam and must never point the beam towards the eye.
- What signage may be useful for the area where levelling is being conducted? Provide an example.
Using caution laser levelling.
- List 3 different tools that could be used to obtain a level mark on the pegs of profile. Identify an advantage/disadvantage for each method.
- Dumpy level:Advantage-The construction is simple with few movable pars.
Disadvantage- It is limitedto only horizontal angle measurement.
- Laser level: Advantage-The usage is easy
Disadvantage-They are very precise and it should be maintained for working properly.
- Spirit level: Advantage-high measurement precision.
Disadvantage-It is good only for the distancethat is short.
- What are 4 advantages of hydrostatic (water) level?
- The main advantage is that the usage is easy and it is cheap to buy.
- Round corners can be used
- Only one person is the operator
- It is very effective.
- How can a spirit level be checked for accuracy?
- On the flat surface, the level should be placed.
- Two marks should be made: one at the end of the level.
- Reading of bubble’s position should be taken.
- Second reading should be taken.
- If the water in the water level tubes is not the same height when the tubes are checked by putting them beside each other, then what would be the most likely cause?
Air bubble in the tube.
- List 8 pieces of equipment that is needed for field levelling work with a laser or optical level.
Following are the equipment that is needed for field:
- Tripod
- Measuring tape
- Marketing tool
- Wooden peg
- Steel peg
- Cutting tools
- Percussions tools
- What are the boning rods, and what are they used for?
Boning rods are used for checking the strategies line between the two points that are fixed. They are made out of timber with their cross-rails painted.
- Does a staff need to be used whenever an optical level is used: and if not what else can be used?
- PC of timber
- Pencils
- Tape measure
- What sources of information would you refer to, to determine what materials are needed for the project, and how many you will need?
Plans and specifications needed to be checked.
- What is a two peg test used for?
The accuracy of a level needs to be checked in the field taking the reading from the instrument.
- List 3 things that a worker could do that would affect the environment while they are performing levelling.
Following are the 3 things:
- Discarding of string lines
- Nails on the ground
- Leaving of pegs in the ground
- Outline 6 steps to correctly set up and stabilise a tripod.
- Payload of both head and legs needs to be checked.
- Feet for rubber spikes needs to be checked.
- Legs should be extended in right order.
- Centre column should only be extended.
- Use the hook.
- Don’t over tighten.
- Describe the 4 main steps setting up an optical level.
- On tripod, levelling instrument should be mounted. Make annual adjustment if it is necessary.
- Optical level around 1280 degree Celsius should be swing.
- Optical level should be returned to the starting position.
- Base plate adjustment should be used for bringing the bubble in attached spirit level.
- Define the below terms.
Levelling:Measurement of the height at a point that is above or below another point is a level.
Datum:An immovable point that doesn’t change is datum.
Benchmark:It is also known as |AHD markers. These are permanent height reference marks that is recognised by the government authorities.
- If the water in the water level tubes is not the same height when the tubes are checked by putting them beside each other, then what would be the most likely cause?
Air bubbles in the tube.
- Record each of the readings in the table below.
Backsight (BS) |
Intermediate Sight (IS) |
Foresight (FS) |
Rise + |
Fall - |
Reduced Level |
Comments |
1.125 |
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100.00 |
TBM |
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3.260
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IS |
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2.755
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IS |
1.660 |
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1.765 |
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- Round corners can be used
- only one person is the operator
- it is very effective
- What is the reason for conducting a 3 part test after completing rise and fall booking sheets?
New station number should be recorded.
As from station 2, this is the first reading. So that the reading is entered into the back sight column.
- Explain how the accuracy of readings is checked using the rise and field method of calculation.
By calculation of the rise and fall between the sequential readings, the levels are determined. The level is fallen if second reading is higher than the first & vice-versa.
- Why it is best practice to use a table to write up the results of field working sightings?
- Station number should be recorded
- Height of datum should be recorded
- Back sight reading should be recorded
- For identification of the point, the comment column should be used.
- Outline the 4 basic steps for setting up a laser level.
- Laser level should be securely mounted on a tripod.
- Required rotation speed should be selected
- Before the self-levelling is complete, the laser head may begin to rotate.
- Power button of the instrument should be pressed, allowing enough time for self-level for the laser.
- Describe 2 methods that could be used to mark a line on the outside of a wall that is 6 m long for a pitching plate for a veranda.
Method 1: For reference, the brickwork course should be used.
Method 2: For reference, the brickwork course should be used
- Describe the 4-step process for taking a reading using a laser level.
- Laser receiver should be mounted on the staff.
- In upward and downward direction, the receiver should slowly move.
- Measurement at the indicator line should be read.
- Indicator should be used as a guide.
- Any level reading taken on site must be recorded. Outline 4 reasons for recording levels in a field book.
- For surveying and preparing of small scale maps, it is the most used method.
- As the surveying and plotting is done simultaneously, all human and machine errors can be eliminated.
- The importance of plan table survey is found in the place high magnetic fluctuation.
- It is one of the most rapid surveying techniques.
- Explain the following terms.
Back sight: Reading taken back towards point of known evaluation.
Fore sight: Reading looking forward to point of unknown points.
Intermediate sight: Reading taken between fore sight and back sight.
Reduced level: The distance between a survey point and datum point with the aim to establish levels.
Datum: It is the starting reference point to survey sight.
- Outline 4 levelling errors that the instrument operator can make.
- Instrument is set incorrectly
- Handling of the equipment is incorrect
- Errors in reading
- Errors in recording
- Detail how reduced levels are calculated.
Calculation of reduced levels are done by adding the rise and subtracting the fall.
- How do you calculate distance using stadia lines?
Measurements that are marked on the stadia rod that is shown between the two stadia marking should be read. The formula of calculating the distance is D=R*S. |
Whereas, D= Rod Reading multiplied by the Stadia markings.
- List 3 important points to remember when using a levelling staff and briefly describe how to read a level using a levelling staff.
- Overhead electric wires are watched out.
- The staff should be kept vertical
- Make sure that at the bottom of the staff there is no mud
- After levelling exercises, how should the work area be left when finished?
- Disposing the waste material.
- Equipment should be cleaned, maintained and stored.
- Areas should be cleaned.
- Give 5 examples on what can be done to levelling tools when packing up, so they are ready for the next job.
- Political and laser should always be transported in padded containers
- Levelling instrument should never be lifted by their external components
- Exposing levelling instrument should be avoided
- Plastic rain should be used for protecting the levelling instrument when working in wet or damp condition.
- Accessories like tripods are compatible, this needs to be made sure.