Surveying Fieldwork PDF

Surveying Fieldwork  Field Notes Constitute the only reliable and permanent record of actual work done in the field. If notes are incorrect or incompletely done – time, money and effort in data gathering are wasted. The quality of field work is reflected directly in th...

Surveying Fieldwork  Field Notes Constitute the only reliable and permanent record of actual work done in the field. If notes are incorrect or incompletely done – time, money and effort in data gathering are wasted. The quality of field work is reflected directly in the manner he keeps his field record. Field notes become the official record of the survey.  Field Notes Types of Field Notes: 1. Sketches 2. Tabulations 3. Explanatory notes 4. Computations 5. Combination  Field Notes Information Found in Fieldbooks: 1. Title or Name of the Project 2. Time of Day and Date 3. Weather Conditions 4. Names of Group Members and Their Designations 5. List of Equipment  Recording Observed Data To eliminate common mistakes in note keeping, the following guide points are given: 1. Follow a consistent simple style of writing. 2. Use of sharp pencil. 3. Record directly in the field book immediately following a measurement, rather than on a sheet of scratch paper for copying.  Recording Observed Data 4. Do not erase recorded data. If a number has been recorded incorrectly, a line is run through it without destroying its legibility and the correct value is written above the mistake. If entire page is to be deleted, diagonal lines are drawn from opposite corners and “VOID” is lettered prominently. 5. Avoid crowding observed data. 6. Always bring along a straight edge for ruling lines, and a small protractor for laying off angles.  Recording Observed Data 7. To avoid misinterpretation of data, use sketches other than tabulations. Also use explanatory notes. 8. Indicate north at the top of the page of the field notebook for all sketches shown in plan and draw a meridian arrow. 9. Tabulated values should be kept inside the column rulings, with the decimal point and digits aligned vertically. Notes should not be made to appear either more precise or less precise than they really are.  Recording Observed Data 10. Computations made in the field should be recorded in the field notebook in order that they can be checked later. The checks are necessary to determine if there is a need to repeat a particular observation or measurement. 11. Number every page of the field notebook. There should be no doubt with regard to the correct sequence of recorded field data.  Survey Party Chief of Party Rear Tapeman Assistant Chief of Flagman Party Rodman Instrument man Pacer Technician Axeman or Lineman Data processor Aidman Recorder Utilitymen Head Tapeman  Survey Hand Signals An arm and hand signal is any gesture or motion that conveys information or gives a command, direction or warning. Usually employed due to the difficulty to communicate verbally in the field due to distance, wind conditions, and surrounding noise.  Care and Handling of Instruments Know how to use the instrument. Always place them in stable grounds when in use. Place them properly in their container. Do not use them if weather does not permit. Check their functionality before and after field work.  Care and Handling of Instruments If wet, dry them by carefully wiping excess water and do not put them immediately in their storage or container. Carry the instrument properly Be mindful of the surrounding when transporting any equipment. Avoid playing with the instrument. Always make sure that the equipment is secure. Introduction to Surveying  Geomatics The science concerned with the measurement, representation, analysis, management, retrieval and, display of spatial information describing both the Earth's physical features and the built-in environment.  Includes disciplines such as: – Surveying – Geodesy – Remote Sensing and Photogrammetry – Cartography – Geographic Information Systems – Global Positioning Systems  Geomatics (Traditional Definition) The art of making measurements of the relative positions of natural and man- made features on the earth's surface, and the presentation of this information either graphically or numerically.  Geomatics (Modern Definition) The art and science of determining angular and linear measurements to establish the form, extent, and relative position of points, lines, and areas on or near the surface of the earth or on other extraterrestrial bodies through applied mathematics and the use of specialized equipment and techniques. In Babylon In Egypt Eratosthenes “What can be mapped, could be ruled.” In 1990 The military requirements of World Wars I and II provided the motivation for vast improvements in the design of surveying equipment and execution of surveying operations.  Uses of Survey 1. Establishment of boundaries of land. 2. Fixing of national and state boundaries. 3. Charting of coastlines and navigable streams and lakes. 4. Precise location of definite reference points throughout the country. 5. Collection of valuable facts concerning the earth’s magnetism at widely scattered stations throughout the country.  Surveying Plane Surveying – the type of surveying in which the mean surface of the earth is considered as a plane, or in which its spheroidal shape is neglected. Geodetic Surveying – takes into account the true shape of the earth.  Types of Surveys 1. Control Survey – consists of establishment of the horizontal and vertical positions of arbitrary points. 2. Property Survey – performed to determine the length and direction of lot lines and to establish the position of these lines on the ground.  Types of Surveys 3. Topographic Survey – made to secure data from which may be made a topographic map indicating the configuration of the terrain and the location of natural and human-made objects.  Types of Surveys 4. Hydrographic Survey – refers to surveys of bodies of water for the purposes of navigation, water supply, or subaqueous construction.  Types of Surveys 5. Mine Survey – utilizes the principles for land, geologic and topographic surveying to control, locate and map underground and surface works related to mining operations.  Types of Surveys 6. Route survey – refers to those control, topographic, and construction surveys necessary for the location and construction of lines of transportation, etc.  Types of Surveys 7. Construction Survey – performed to lay out, locate and, monitor public and private engineering works.  Types of Surveys 8. Photogrammetric Survey – measurements made on photographs are used to determine the positions of photographed objects.  Definition of Terms Total Station System Digital Photogrammetry and Remote Sensing Satellite Positioning System Geographic and Land Information Systems  Definition of Terms Level surface – a curved surface every element of which is normal to a line that is directed exactly toward the Earth's center of gravity (plumb line). Zenith – direction away from the center of the Earth and above the observer’s head. Nadir – direction towards the center of the Earth.  Definition of Terms Horizontal plane – plane tangent to a level surface at a particular point. Horizontal line – a line tangent to a level surface. In surveying, it is commonly understood that a horizontal line of sight is straight. Horizontal angle – an angle formed by the intersection of two lines in a horizontal plane.  Definition of Terms Vertical line – a line perpendicular to the horizontal plane. Vertical plane – is a plane in which a vertical line is an element. Vertical angle – angle between two intersecting lines in a vertical plane.  Definition of Terms Zenith angle – angle between two lines in a vertical plane where it is understood that one of the lines is directed toward the zenith. Nadir angle – angle between two lines in a vertical plane where it is understood that one of the lines is directed toward the nadir.  Definition of Terms Horizontal distances – distances measured along a level line. Elevation of a point – vertical distance above (or below) some arbitrarily assumed level surface, or datum. Contour – an imaginary line of constant elevation on the ground surface.  Definition of Terms Difference in elevation – vertical distance between two points. Leveling – operation of measuring difference in elevation. Grade or Gradient of a line – slope of the line or rate of ascent or descent. REFERENCES Becker, B.J. Eratosthenes of Cyrene. http://www.mlahanas.de/Greeks/Eratosthenes.htm ptolemy.eecs.berkeley.edu/ people/ptolemy.htm Buckner (1994). http://surveying.mentabolism.org/buckner.html. Last Accessed 16June08 Center for Advanced Spatial Technologies, University of Arkansas. http://www.cast.uark.edu/home/research/geomatics.html Davis, R.E., et. al (1981). Surveying: Theory and Practice. USA: McGraw-Hill, Inc. Federation of American Scientists. Html link lost Great Pyramid of Khufu. http://vncafe.blogspot.com/2008/03/great- pyramid-of-giza.html REFERENCES International Federation of Surveyors. http://www.surveyor.asn.au/for-the-public/international- definition-of-surveyor.php La Putt, J.P. (2007). Elementary Surveying. Philippines: National Book Store. ManSurveying.gif. From http://everythingaboutsurveying.blogspot.com/2008/05/geodetic- instrumentation-methods.html http://surveying.mentabolism.org/geomatic.htm. From the Dept. of Surveying and Spatial Information Science, Univ. of Tasmania. Link (broken): http://info.utas.edu.au/docs/geomatics/geomatics_exp.html