INTRODUCTION
The purpose of this practical assignment is to test your ability to carry out the field work detail survey and process the data of a small area. The detail survey is to be conducted for the purpose of future construction work; you will need to decide on what detail will be relevant and what does not need to be recorded.
TASK
In your practical group, you are in turn to:
- Set up the job (s) on the total station and enter the codes required, thus setting up your code library, additional codes can be added in field if required.
- Using the existing Permanent control points bring horizontal and vertical control into the area that is designated, by first identifying the locations of your station points and level these in, then use the total stations to bring horizontal control to the area and ensure that you close back onto the permanent markers, to an accuracy of 1:10,000. You will need to conduct a resection initially, both by using the total stations and by hand (using the formulas demonstrated in the lecture).
- Conduct the survey ensuring that you have recorded sufficient data points to adequately portray the area. I believe something in excess of 1000 points will define the area.
- The detail that you are required to record includes the location of existing services and infrastructure (pits, footpaths, man-made features), natural features including natural surface levels, trees, waterways and water bodies.
- Make sure you record a minimum of two recoverable points each week. I.e. these can be signs or something that can be located precisely. When you go out the following week, you need to record the location of these two points again for reference, so you have something to tie your weeks together and so that you can check the orientation of your data for each week.
- The data should be downloaded each week before the commencement of the next practical session, preferably at the conclusion of each practical session. (refer to instructions for downloading the instruments on the lms).
- The downloaded data should be in the form of an ASCII file. This can be opened in Notepad (do this just to check that it has downloaded correctly).
- Once you have noted the form of the data (i.e. PENZD or PNEZD comma or space delineated) you can import your points directly into the template (download this from the lms) for AutoCAD, note you can import the points into CAD using any computer running Civil 3D but the downloading of the data needs to be completed on the computers located in the storeroom.
- You will add to this file every week. Take note of any corrections that may need to be made (i.e. wrongly oriented survey data etc).
- Produce the detail survey on the appropriate CAD program.
The coordinates you will need are;
|
Point
|
Easting
|
Northing
|
RL
|
|
TBM1
|
327717.915
|
5823323.828
|
73.912
|
|
TBM2
|
327763.876
|
5823325.357
|
71.742
|
|
TBM3
|
327791.465
|
5823326.028
|
71.575
|
TIPS FOR CONDUCTING A SUCCESSFUL DETAIL SURVEY
o Plan the survey in advance. Look at the area; decide on the features/detail which needs to be recorded.
o Decide on how control is going to be brought to the area.
o Plan the location of your station points and set up your control network first, ensuring that the entire area can be covered from your station points (record these points first).
o Plan the order that you are going to record the detail in (hint: boundaries are generally recorded and established first).
o Traverse through the area, using your control points and record all relevant detail.
o Always download your data at the end of each practical session to isolate errors which may have occurred in any practical.
o Always keep a copy of your raw data as backup.
o Save a copy of each practical session's work in a separate file.
WRITE UP AND RESULTS
Expected layout of Practical Report:
1. Introduction
o Clear outline of what the practical exercise entails and what is included in the report i.e. the form that the results will take etc, 200 - 250 words.
2. Equipment and Method
o A list of the equipment that you used for your practical.
o A clear concise outline of "YOUR" method. It should be written in such a way that someone having only your practical report could go and complete the practical following your methodology. It can take either paragraph form or dot point form. Your method should be descriptive and written in past tense. It should include how you approached the survey including the order in which the detail was recorded. DO NOT include what buttons etc you pressed on the total station to record the detail (this is excessive detail). DO include what you recorded each week.
3. Results
o A copy of your resection calculations and a comparison between these and the coordinates obtained from the total station including the margin of error.
o An A3 pdf of your Detail survey. It does not have to be in colour, however varying line types and thicknesses are recommended to help distinguish between features such as footpaths, fences and drainage lines. Your printout should include the following essentials:
A completed title block with the date of the survey, where the area is located, plan number, who completed the survey,
scale,
north point,
border,
legend,
Appropriate dimensions and labeling - remembering the detail survey was for the purpose of future construction work, therefore the plan should provide information that can be used for this purpose.
o An A3 pdf of your digital terrain model surface showing your TIN complete with breaklines, highlighting drainage and other features.
o A copy of your raw survey data (ascii format) and your surface data.
o Quantification of errors encountered in the field (both linear and angular), this can found by closing back to one of the permanent markers.
4. Discussion
o Discussion of "YOUR" results. This should include justification for the level of accuracy achieved along with any difficulties experienced during the practical exercise. Suggestions for how you could have achieved more accurate results should also be included. Please note: any suggestions on how you could achieve more accurate results need to be realistic, achievable and does not include changing equipment or going out on a different day in more favorable weather conditions.