CIV2SUR surveying Assignment

Surveying (CIV2SUR) 
Circular Curve Layout 
La Trobe University 

INTRODUCTION

Circular curves are used in road design. They are used to connect two intersecting straight roads, providing ease of travel and a smooth transition when changing direction. The purpose of this practical assignment is to test your ability to operate a Total Station in laying out works and to test your ability to perform the calculations necessary to provide the data to layout a circular curve.

EQUIPMENT

Total Station

Roving reflector

Measuring tape

1 x pair of Walkie Talkies

TASK

  • Calculate the data necessary and complete the curve data sheet, to layout one of the nominated curves outlined in this practical handout in 10 metre pegging intervals, this includes but is not limitedto: o intersection angle, o tangent distance, o half angle, o external secant o long chord,

o distance to the crown from the tangent points, o deflection angles and corresponding long chords.

All checks should be made for the calculated data to ensure that it is accurate and there are no calculation errors.

This is an individual requirement, this is required to be completed and signed off before thecommencement of the practical, if you do not have a complete set of calculations before the practical,you will not be allowed to participate and hence be unable to submit a practical report.

  • Peg out the curve, with your nominated practical group, by using a similar methodology to the following (NOTE: this is a brief generalized method only): o Set up over your intersection point and zero your instrument along your first tangent line, measure and peg your first tangent point.
    • Repeat for your second tangent point.
    • Set up over your first tangent point and peg your curve until the crown using your calculated deflection angles and long chords,
    • Repeat from the other tangent point, pegging back to the crown.
    • The difference between the two pegs placed for the crown is your error.
  • RECORD THE DESCREPENCIES BOTH IN THE ANGULAR AND LINEAR DIRECTION, MAXIMUM ALLOWABLE LINEAR MISCLOSE IS 100mm, MAXIMUM ALLOWABLE ANGULAR MISCLOSE IS 30SEC.

Groups and Curve Data

Note; the intersection point for each curve is highlighted in the tables.

Groups

Radius

Chainage of

Intersection

Point

1

95

180.564

2

100

203.222

3

92

130.236

4

80

101.555

5

95

130.000

6

101

265.120

Group 1

Points

Easting

Northing

1

327495.737

5823117.846

7

327419.027

5823254.242

10

327488.709

5823304.026

Group 2

Points

Easting

Northing

3

327439.297

5823139.484

8

327435.649

5823279.535

12

327544.156

5823283.413

Group 3

Points

Easting

Northing

4

327420.974

5823163.279

17

327542.041

5823135.296

13

327563.927

5823260.460

Group 4

Points

Easting

Northing

5

327411.799

5823191.200

11

327518.480

5823299.430

14

327573.355

5823231.889

Group 5

Points

Easting

Northing

10

327488.709

5823304.026

15

327575.747

5823201.590

1

327495.737

5823117.846

Groups 6

Points

Easting

Northing

12

327544.156

5823283.413

16

327568.173

5823172.049

2

327466.149

5823121.842

WRITE UP AND RESULTS

Expected layout of Practical Report:

  1. Introduction
    • Provide a context for your practical, a 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. Materials and Methods o A list of the equipment that you used for your practical.
    • A clear concise outline of YOUR” 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 should be written in past tense and personal tense should be avoided. It should be specific to your practical.
  3. Results
    • Your completed and signed curve sheet as well any additional calculations required to accurately peg out the curve.
    • Quantification of errors encountered in the field (both linear and angular).
  4. Discussion o Discussion of your results and the level of accuracy achieved. Include any problems experienced infield and suggestions on how errors could be minimised should the practical be conducted again. Do the practical results fall within specifications?
    • Note: suggested improvements or changes in your methodology need to be practical and be based on the given equipment for the practical. 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 favourable weather conditions.
    • Your discussion needs to be an objective analysis of the practical task.

The practical write up will be marked according to the following rubric

La Trobe University

Criteria*

Unsatisfactory

Satisfactory

More than satisfactory

Introduction (max. 200-250 words) 5 marks

Marking

0 – 2

2.5 – 3.5

4 – 5

Identifies and uses relevant information to provide a context for the investigation. Begins with general information and ends with the specifics: ‘in this report…’

Description is difficult to follow and/or not in accepted engineering style, and/or lacks detail

A brief background, context and practical specifics are given although there are minor problems with sentence construction and may be missing minor details.

A clear background and context are provided for the practical and the objectives are clearly outlined.

Materials and

Methods

10 marks

Marking

0 – 4.5

5 – 8

8.5 – 10

Describe the procedures, used in the investigation concisely and logically

Description is difficult to follow and/or not in accepted engineering style, and/or lacks detail

Procedures are described in logical order, although there are minor problems with sentence construction.

Procedures are described concisely, in logical order, using appropriate scientific terminology.

Results 40 marks

Marking

0 – 9.5

10 – 15

15.5 – 20

Completed and signed Curve sheet and additional calculations required to complete the practical exercise*

(20 marks)

Curve sheet not included or incomplete curve sheet, not signed or incorrect calculations.

Signed and completed curve sheet with accompanying calculations.

Signed and completed curve sheet with accompanying calculations. All calculations checked and quoted to the correct level of accuracy.

Marking

0 – 9.5

10 – 15

15.5 – 20

Experimental error/uncertainty for both angular and linear parameters accurately quantified.

(20 marks)

Data presented without consideration of certainty and/or estimate of certainty not presented. Errors fall well outside of specifications.

Errors quantified/estimated for either linear or angular parameters but not both. Errors fall just within specifications.

Errors are clearly identified in both parameters. All calculated parameters are shown with the correct level of accuracy.

Errors are well within specifications.

Discussion

35 marks

Marking

0 – 17.5

18 – 29

30 – 35

Interprets data and draws valid conclusions. Discusses specifications and methodological issues relating to the accuracy of results.

Data is re-stated rather than interpreted, there are no references to specifications and methodological issues.

Data is summarised and interpreted but there is little reference to a conclusion and its validity. The discussion of specifications and methodological issues.

Data is summarised and interpreted and any limitations of the conclusion are clearly spelt out. The student demonstrates a good understanding of specifications and methodology. Ideas are presented in a logical and insightful manner.

Referencing and

presentation

5 marks

Marking

0 – 2

2.5 – 3.5

4 – 5

Professionally presented report. Well structured, with clearly defined sections. All diagrams and tables are clear, labelled and appropriate. Report is appropriately referenced (APA 6 format)

Major inconsistencies in formatting Poor presentation, torn pages, poorly presented diagrams and tables. No referencing or incorrect format for intext/reference list.

Appropriate in-text referencing and a correctly formatted reference list. Minor inconsistencies in referencing style and in the format of the report.

Text, tables and diagrams are correctly formatted. The report is well structured and professionally presented. Appropriate in-text referencing and reference list.

** English

Expression

5 marks

Marking

0 – 2

2.5 – 3.5

4 – 5

Communicates clearly using scientific conventions

Incorrect sentence structure, punctuation and inappropriate vocabulary make it hard work to read the report. Language lacks academic and scientific conventions.

Ideas are expressed in a formal academic style, although there may be minor sentence structure, punctuation and spelling errors.

Ideas are eloquently expressed in a formal academic style, using appropriate vocabulary There are no, or very few, grammar, punctuation and spelling errors.