Assignment 1 2015 - Land Surveying 2 Construction Setout

Transcription

Assignment 1 2015 - Land Surveying 2 Construction Setout
Unitec Institute of Technology
Land Surveying 2 (2015)
(ENGG & DE6207)
Assignment No. 1
(10% of total course)
“Building Setout”
Due Date: 01 April 2015
Land Surveying 2 (ENGG_DE6207): Assignment 1 2015 - Land Surveying 2 Construction Setout.docx
Introduction
Setting out is one of the many functions a Surveyor is required to undertake. Almost
every construction project requires some degree of set out, and as such it is an
important skill to understand and learn.
Correct set out is required for different purposes.
Some examples of which are as follows:
 Where proximity to legal boundaries is to be respected as required, & to ensure
height to boundary regulations are not infringed.
 Correct distance from other structures if maintained.
 Separate structures are correctly set out and aligned (e.g. bridge abutments and
piers)
 Required orientation of building for solar gain or rejection.
 Positioning and aligning of buildings to ensure minimal earthworks are required.
 Services correctly positioned in floor slabs.
 Ensuring the building is on the correct Lot # (it has happened!), and at the
appropriate offsets specified within approved Council plans or consent conditions
as granted.
In general, setting out details are usually provided to surveyors in plan form, either
electronically or in hard copy format. Plans may indicate specific setting out
requirements however in many small scale jobs it is up to the Surveyor (often but not
always in consultation with the builder) who decides what points need setting out and
how to achieve it. On-the-job calculations can be required with perhaps a construction
crew waiting impatiently, so an ability to read and understand plans is needed to avoid
mistakes and to ensure correct positioning is achieved. Remember, mistakes are costly,
both in terms of rework, as well as compensation in extreme cases.
Any set out pegs/profiles etc must be carefully positioned, labelled and referred back to
the plans. As any pegs in the work area can (and often are) knocked or removed, offset
pegs are sometimes required with distances from each noted on the plan so the builders
can tape to the required point.
As per normal surveying practice, any building set out needs to be able to be
independently checked. This can involve different methods, for example:
 Checking the diagonals with an accurate tape measure (remember your
accuracies!)
 Setting up over a second point and re-doing the calculations and set out.
 Measuring between each peg and checking that the plan distances match /
correlate.
 Finding local north and checking the appropriate wall is aligned.
 Checking right angle corners wherever possible.
 Ensure that each corner peg has an accurate RL to the top of the peg. This will
be needed to enable future setout of the main floor level.
In general, the main criterion is to have sufficient redundancy to ensure any gross errors
are found and rectified. This is normally achieved by completing independent check
observations and measurements.
Land Surveying 2 (ENGG_DE6207): Assignment 1 2015 - Land Surveying 2 Construction Setout.docx
Assignment Details
Attached is a basic house plan which your group (2 people) is required to set out. The
setout location is within the Unitec campus area, adjacent to the main stormwater pond
immediately below Building 172 (IBM Building).
Each group will need to determine an appropriate orientation for the line between points
A and C, as the basis for their set-out calculations. It is recommended that once you
decide on the appropriate survey mark from which to complete the setting out exercise,
at that point determine the orientation that best suits the building profile.
The required accuracy limits for the building setout are as follows:
Positional Accuracy
Accuracy Limit
Horizontal position
Height tolerance
5mm (RMS)
2mm (RMS)
BEFORE setting out, check that either David Poyner or I am available to check and
mark your work.
1. Each group is to choose one of the Unitec survey field marks (A to H, ITUN2, or
ISUN7). Do not use D1 or Pukeko as a setup point. Check your set out will not
clash with another groups.
2. Choose appropriate equipment and methodology to use.
3. A coordinate schedule (Appendix A herein) is provided for the main Unitec
survey marks.
4. Place your starting peg, calculate and place remaining pegs. Note* - Any pegs
needed to be placed in the pond, garden, road, footpath, rockwall, stream
or other inappropriate position will result in a 0 mark being given. In other
words, take care in deciding where to set out your building outline.
5. Place offset pegs for building points A to J. Use an offset distance of 1 metre
from the outer walls for all offsets.
6. Place setout pegs at the waste pipe locations (W1 & W5) shown on the attached
plan.
7. All building corner pegs as marked on the ground will need to have an accurate
reduced level (RL) for the top of the peg, in line with the stated height tolerance
limit specified above. Respective offsets to your selected main finished floor
level will then be specified in the report document submitted.
8. Complete appropriate independent site checks to ensure the building is
accurately set-out on the ground, the main building corners are perpendicular,
and that respective positional accuracies (as stated above) are met or exceeded.
9. Request marking. Only on satisfactory completion of this facet, and with the
approval from the marker, can pegs then be removed.
10. Remove and return pegs and equipment.
Land Surveying 2 (ENGG_DE6207): Assignment 1 2015 - Land Surveying 2 Construction Setout.docx
Report Format
This final assignment presentation is to be a short report structure using a conventional
word processing package.
The various elements contained within this format are as follows:
 Group details
 Setting out location, marks used, etc
 Calculations
 Setting out methods and process
 Independent field checks & office verification records, including field
notes.
 Presentation of final setting out results, including independent checks
 Summary & conclusions
Note that presentation is important, so make the effort to submit a report of suitable
quality and content.
Total mark for this section of the assignment will be 10% of the total course mark.
Due date for this assignment will be 01 April 2015.
Please note that, due to competing workload & assignments from other NDS papers,
you will need to check with David Poyner as to the availability of equipment to complete
this assignment. In other words, give him plenty of notice and book in a time well in
advance.
Land Surveying 2 (ENGG_DE6207): Assignment 1 2015 - Land Surveying 2 Construction Setout.docx
Appendix A – Coordinate Schedule
Land Surveying 2 (ENGG_DE6207) – 2015
Assignment 1 – 2015 (Building Set out)
Coordinates from 5th Order survey origin points
(extracted from observation data June 2013).
Code
Easting
Northing
Ak. MSL Height
WCA_B3
395077.59
800152.54
22.26
H4
395012.89
800055.71
20.16
ISD1
395036.60
800001.29
21.89
ISUN6
394970.36
800221.77
14.70
ISUN7
394912.82
800133.92
18.37
ITUN2
395052.88
799933.56
23.64
PUKEKO
395047.68
799990.36
22.62
Land Surveying 2 (ENGG_DE6207): Assignment 1 2015 - Land Surveying 2 Construction Setout.docx