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Surveying With Construction Applications, 7th Edition

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1 Surveying With Construction Applications, 7th Edition
Chapter 1 Surveying Fundamentals

2 What is Surveying? Surveying is the art and science of of taking field measurements on or near the surface of the earth. Surveying measurements include horizontal and slope distances,vertical distances, horizontal and vertical angles and positions. Surveying With Construction Applications, 7th Edition Barry F. Kavanagh

3 What is surveying? Why it is an art?
Surveying is the art of measuring distances, angles and positions on or near the surface of the earth. Why it is an art? Because only a surveyor who possesses through understanding of surveying techniques will be able to determine the most efficient methods required to obtain optimal results over a wide variety of surveying problems.

4 Why it is scientific? Because the use of mathematical techniques to analyze field data, accuracy and reliability depends on understanding scientific principles underlying and affecting survey measurement.

5 What is Geomatics? Geomatics is a term describing the computerization and digitization of data collection, data processing, data analysis and data output. Surveying With Construction Applications, 7th Edition Barry F. Kavanagh

6 What is Engineering Surveying?
Engineering surveying includes those activities involved in the planning and execution of surveys for the location, design, construction, maintenance and operation of civil and other engineered projects. Surveying With Construction Applications, 7th Edition Barry F. Kavanagh

7 What activities are included in engineering surveying?
Preparation of surveying and related mapping specifications. Execution of remote sensing and field surveys for the collection of required data – including topographic and hydrographic data. Calculation, reduction, and plotting (manual and computer-aided) of survey data for use in engineering design. Design and provision of horizontal and vertical control networks Provision of line and grade for construction. Measurement of materials and other quantities for inventory, cost accounting, and payment purposes. Execution of as-built surveys and plans. Surveying With Construction Applications, 7th Edition Barry F. Kavanagh

8 Types of Surveying Plane surveying is that type of surveying in which the surface of the earth is considered to be a plane for all X and Y dimensions. Geodetic surveying is that type of survey in which the earth is considered to be ellipsoidal in shape for all X and Y dimensions. Surveying With Construction Applications, 7th Edition Barry F. Kavanagh

9 What are the two most common applications of surveying?
The location of ground features (natural and built) are measured to prepare a plan or map of the area. Design features, shown on an engineering plan, are located in the field by distance and angle measurements or through positioning techniques. Surveying With Construction Applications, 7th Edition Barry F. Kavanagh

10 Classes of Surveys Preliminary survey. Rectangular tie-ins
Polar tie-ins Intersection tie-ins Positioning tie-ins Layout survey. Rectangular layout Polar layout Positioning layout Machine guidance and control Control survey. Surveying With Construction Applications, 7th Edition Barry F. Kavanagh

11 Classes of surveys Preliminary survey: (data gathering ) is the gathering of data (distances, position and angles) to locate physical features (rivers, roads, structures) so that data can be plotted to scale (map or plan), also include diff. in elevation so that contour could be plotted.

12 Layout survey: Marking on the ground using sticks iron bar or concrete monuments. The features shown on a design plan features: - Property lines (subdivision survey). - Engineering work (construction survey). - Z-dimensions are given for x-y directions. Control survey: used to reference prelim and layout surveys. Horizontal control: arbitrary line tied to prop line or HWY center or coordinated control stations.

13 Vertical control: Benchmarks: points whose elev
Vertical control: Benchmarks: points whose elev. above sea level is carefully determined. - In Control survey more care to accuracy. - Control lines should be easy to re-establish.

14 Location Ties Surveying With Construction Applications, 7th Edition
Barry F. Kavanagh

15 Surveying Fields Topographic Surveys Hydrographic surveys
Route surveys Property Surveys Aerial Surveys Construction surveys Final (As-Built) Surveys Surveying With Construction Applications, 7th Edition Barry F. Kavanagh

16 Definitions 1- Topographic survey: preliminary surveys used to tie earth surface features. 2- Hydrographic survey: preliminary surveys tie underwater feature to surface control line 3- Route surveys: preliminary, layout and control surveys that range over a narrow but long strip of land (highways, railroads, electricity transmission lines and channels).

17 4- Property surveys: preliminary, layout and control surveys determine boundary locations for a new map. 5- Aerial survey: preliminary and final surveys convert aerial photograph into scale map using photogram metric tech. 6- Construction survey: layout of engineering work. 7- Final (as built) survey: preliminary surveys tie in features that just have been constructed

18 Unit of Measurement There are two main measuring systems:
English system and Metric system (SI units). - All countries will change to Metric system. - Angles are measured by: Degrees, minutes and seconds. - 1 revolution = 360 degrees, 1 degree = 60 minutes and 1 minutes = 60 seconds.

19 Units of Measurement Surveying With Construction Applications, 7th Edition Barry F. Kavanagh

20 Steel tape Level ( stadia principle ) Total station Thedilite GPS

21 Surveying Instrument 1- Transit and theodolite: Establish straight or curved lines, horizontal and vertical angles. 2- The level and rod: measure difference in elevations. 3- Steel tape: measure horizontal and slope distances. 4- Total station. 5- GPS (global positioning system) receivers.

22 Survey Equipment – Steel Tape
Surveying With Construction Applications, 7th Edition Barry F. Kavanagh

23 Survey Equipment – Automatic Level
Surveying With Construction Applications, 7th Edition Barry F. Kavanagh

24 Leveling Technique Surveying With Construction Applications, 7th Edition Barry F. Kavanagh

25 Surveying Equipment – Electronic Theodolite
Surveying With Construction Applications, 7th Edition Barry F. Kavanagh

26 Surveying Equipment – Total Station
Surveying With Construction Applications, 7th Edition Barry F. Kavanagh

27 1.17 Stationing Along Baseline: stations or chainage
At right angle: offset dist. Beg ft (m). 0+00 2+50 4+96

28 Stationing Stations are dimensions measured along a baseline
The beginning point is described as 0+00 A point 100 ft (m) from the beginning is 1+00 A point ft (m) from the beginning is Some highways agencies who have converted to metric, use 1,000 m stations (instead of 100 m). E.g., 0+000, , 1+000, etc. Surveying With Construction Applications, 7th Edition Barry F. Kavanagh

29 Stationing Illustration
Surveying With Construction Applications, 7th Edition Barry F. Kavanagh

30 Accuracy and precision
Accuracy: relationship between measure & true value of measurement. Precision: Degree of refinement with which the measurement is made. Example: True Distance Measured Distance Error Cloth tape Steel tape - More precise method resulted in more accurate. - More precise method may result in less accurate measurement. Example: Repaired tape.

31 Accuracy and Precision
Surveying With Construction Applications, 7th Edition Barry F. Kavanagh

32 Errors Systematic errors are those errors whose magnitude and algebraic sign can be determined. Random errors are associated with the skill and vigilance of the surveyor. They can be minimized but not completely eliminated. Surveying With Construction Applications, 7th Edition Barry F. Kavanagh

33 Errors - No measurement (except count) can be free of error.
True value is determined statistically (mean) to calculate error. Systematic error: error whose magnitude and algebraic sign can be determined and eliminated (temp. error). Random Error: - Error due to surveyor skill. - Tend to cancel each other. - Little significance except for high precision survey. - Unskilled or careless surveyor can make problem. - Large random error doesn’t result in accurate work even if they cancel.

34 Accuracy Ratio Error of closure: The difference between the measured location and the theoretical correct location (repeated measurement, mathematical analysis). Exp. measured distance errors Known distance Accuracy ratio / = 1/4175 = 1/4200 - Fraction whose numerator is unity and denominator closest 100 unit.

35 Mistakes There are many mistakes that cold be happened to surveyors.
- Blunders made by survey personnel e.g. 68 instead of 86. - Miscounting tape length, measuring from wrong point. - Mistakes will occur and must be discovered and eliminated by verifying the measurement (Repeat Geometry analysis, etc.). - Every measurement should be repeated to eliminate mistakes and improved precision.

36 Survey Geographic Reference
Define reference as the surface of earth. Latitude: East/West //equator. - Max angle 90o north or south. Longitude (Meridians): North/South converge at poles & max angle = 180 degree east or west from the plane of 0o longitude Greenwich. - used in geodetic not plane survey. - Plane survey use coordinates grid system.

37 Survey Grid Reference States and provinces have adopted a grid system best suited to their needs. - Limited in size: no serious error due to curvatures. - Easy to use (plane geometry & trigonometry). - Common datum for x & y dimensions. - Easy to translate to geodetic survey.

38 Survey Vertical reference
Vertical dimension can be referenced to any datum. - Mostly used datum is mean sea level MSL = ft. - Benchmarks  permanent points whose elevation has been precisely determined.

39 Distance Measurements
Distance between two points can be horizontal, slope or vertical and are recorded in feet (foot units) of meters (SI units). - Horizontal and slope distances can be measured by using fiberglass, steel tape or EDM (electronic distance measuring) + difference in elevation and slope distance. - Vertical distance can be measured by using tape as in construction work or level and leveling rod

40 Location Methods - (a): right angle offset tie.
B B B P P P C A A A - (a): right angle offset tie. - (b): the angle distance tie (polar tie). - (c): angle at A and B of distance BP of AP (intersection technique).


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