TOPOGRAPHICAL AND SITE SURVEY (Standard Of Procedure)

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1 FACULTY OF CIVIL ENGINEERING & EARTH RESOURCES ENGINEERING SURVEY FIELDWORK TOPOGRAPHICAL AND SITE SURVEY (Standard Of Procedure) Subject Code Date Group Number Student Name & ID Number Group Member Name & ID Number 1 2 Lecturer Marks Remarks Endorsement

2 Objective: 1. To gathered data (i.e. location man-made and natural features) of a parcel of ground within UMP area using radial positioning and tacheometry. 2. To produce of the scaled drawing of a parcel of ground within UMP area. Scope of works: 1. Each group shall be carried out field survey works necessary to accurately determine the locations, level, dimensions and other relevant information on surface features. 2. Each group shall be prepared a plan of site survey had been done. 3. Each group shall be prepared a report of had been done (Appendix III). The report shall be submitted one week after completed the fieldwork. List of Devices: 1. 1 set of Built-in EDM or Theodolite completed with accessories set of Reflector completed with accessories set of Staff completed with accessories. 4. Fieldbook. Procedure of works: 1. Conducting a survey (Appendix II). The traverse line (leg) bearing shall be used as reference. 2. Recording the survey (Appendix III). Measurements must be recorded in permanent ink in the appropriate columns of the observation pages immediately after they are made. Make a reference sketch of the survey, the sketch must be absolutely clear. Determine reduce level for each points 3. Plotting.

3 Appendix I TOPOGRAPHICAL AND SITE SURVEY Introduction: The objective of most surveys is to determine the three-dimensional coordinates x, y and z (easting, northing and elevation) of a series of points of detail. These coordinates are plotted and a contoured plan is compiled from the results. The field methods used is radial positioning using Theodolite with tacheometry technique or using Built-in EDM. Principles of radial positioning: Figure shows illustrate the principles. Station 1 is a survey station with known coordinate (x, y, z). The reference object (RO) is the point chosen as the starting point, from which the bearings of all lines of the survey will be measured. In this case, station 6, can used as RO. Bearing line 1-6, must be known or assumed. Points 1-6 are the points of detail of the survey, e.g. building corners, fence corners, etc. The three-dimensional coordinates of the points are required. Another closed traverse, the traverse begins on two points A and B of known bearing and ends on two different known points C and D. The survey is one again selfchecking in that the bearing of line CD deduced from the traversing should agree with the already known bearing of CD.

4 Appendix II 1. Setting up the Theodolite Setting the tripod The tripod legs are spread out and rested lightly on the ground around the survey point. Judging by eye, the legs are moved to bring the tripod head over the point, keeping the tripod head as level as possible. Mounting the instrument The theodolite is carefully removed from the box and screwed to the tripod. Centring A sight is taken through the optical plummet to view the survey peg. The footscrews are turned to bring the instrument exactly over the peg. The theodolite is now centred but, not level. Levelling Levelling is accompolished by raising or lowering the legs of the tripod, using the sliding leg arrangement, until the circular spirit level is centred. Refinements to the centring and leveling of the instrument must now be made; (a) Set the plate spirit level over two screws and centralize the bubble, (b) Turn the instrument through 90 o and recentralize the bubble (c) Repeat operations (a) and (b) until the bubble remains central for both positions. Parallax elimination A piece of paper is held in front of the telescope and the observer, sighting the paper through the telescope, turns the eyepiece carefully until the cross-wires of the reticule are sharply defined. 2. Setting up bearing to RO (Topcon GTS220) Released Horizontal and vertical plate, and the theodolite in face left position. Switch On Theodolite Display Panel. Make sure horizontal bearing in the mode Horizontal Right (HR). Rotate the theodolite horizontally, till the required horizontal bearing had been display in panel. Refinements to the required horizontal bearing, using horizontal tangent screw. Press the (F2)(HOLD) key. Collimate the target at RO. Press the [F3](YES) key to finish holding the horizontal angle. 3. Measurement to another points using Built-EDM Theodolite. Released Horizontal and vertical plate. Rotate the theodolite horizontally, collimate the center of prism above the point. Horizontal bearing have display. Press the [ ]key. Distance measurement starts. Display panel shows HR (Horizontal angle), HD (horizontal distance) and VD (Vertical distance). Press F1 (Meas). New distance display.

5 Record the measurement (HR, HD and VD) in appropriate column of observation pages. Obtained Height of Instrument and Height of Target. Remarks of object. Determine Reduce Level of points; RL of points = RL of Observ Stn + Height of Inst Height of Target ± Diff Ht 4. Measurement to another points using Theodolite with Tacheometry technique. Released Horizontal and vertical plate. Rotate the theodolite horizontally, collimate the staff above the point. Horizontal bearing and vertical angle have display. Obtained the stadia reading (top, mid and bottom). Obtained Height of Instrument. Record the measurement in appropriate column of observation pages. Remarks of object. Determine; S = Top Bottom H (Horizontal Distance) = 100S Cos 2 h(difference Height) = 100S Cos.Sin = H tan RL of points = RL of Observ Stn + Height of Inst Mid ± Diff Ht - vertical angle Appendix III Observation page (Built-in EDM)

7 Appendix IV Report: Each group shall submit the report one week after completed the fieldwork. The report shall be consisted hereundera) Introduction b) Objective c) Devices d) Procedure e) Product Fieldbook. Plan f) Analysis g) Conclusion

FACULTY OF CIVIL ENGINEERING & EARTH RESOURCES ENGINEERING SURVEY FIELDWORK. CURVE RANGING COMPUTATION & SETTING-OUT (Standard Of Procedure)

FACULTY OF CIVIL ENGINEERING & EARTH RESOURCES ENGINEERING SURVEY FIELDWORK CURVE RANGING COMPUTATION & SETTING-OUT (Standard Of Procedure) Subject Code Date Group Number Student Name & ID Number Group