Elementary surveying in engineering and architecture Field Work Schedule 1st Semester School Year 2017-2018 June 20- 23 Pacing June 27- 30 Taping July 4 - 7 Determining Obstructed Distance July 11- 14 Differential Leveling July 25- 28 Survey of Topography August 15-18 Closed Compass Traversing September 5-8 Traverse Computations September 12-15 Control Survey by Triangulation Video Viewing, Laboratory Refresher and Continuing Training Course, and Field Hands-On Schedule 1st Semester School Year 2017-2018 September 19-22 Setting up of Theodolite September 26-29 Setting up of Level Laboratory safety training and use of digital devices Video Viewing Schedule 1st Semester School Year 2015-2016 September 8-11 Setting up of total station Setting of digital theodolite Setting up of manual theodolite September- October Field Hands-On *************************** Glossary azimuth of line- direction of line given by the angle between the meridian and the line measured in clockwise direction from either the north or south branch of the meridian bearing of line- acute horizontal angle between the reference meridian and the line, describing the direction of the line deflection angle- angle between a line and the prolongation of the preceding line direction of line- horizontal angle the line makes with an established line of reference magnetic declination-(horizontal angle and) direction by which the compass needle deflects from the true meridian magnetic meridian- line which is parallel to the earth's magnetic lines of force magnetic north- north point established by means of the magnetic compass when there are no local attractions affecting it traverse - series of lines (connecting successive points) whose lengths and directions have been determined from field measurements true meridian - line passing through the position of the observer, and the north and south poles of the earth True north - north point of the true meridian Reference La Putt, J. (1987). Elementary Surveying (3rd ed). Philippines: Baguio Research & Publishing Center. ********************************************* LEARNING MATERIAL FOR HYDROGRAPHIC INVESTIGATION THAT INCLUDES RIVER DISCHARGE ESTIMATION, AVERAGE WATER VELOCITY DETERMINATION, AND RIVER CROSS SECTIONAL AREA APPROXIMATION
Fao. (n.d.). Estimates of water flow. ftp://ftp.fao.org/fi/cdrom/fao_training/fao_training/general/x6705e/x6705e03.htm ********************************************* |
References
La Putt, J. P. (1987). Elementary Surveying (3rd ed). Baguio, Baguio Research & Publishing Center. Pacing. (n.d.). courses.washington.edu/fe345/lectures/day_2/assignments_lab/PACING.doc Topographic surveys- direct levelling. (n.d.) ftp://ftp.fao.org/fi/cdrom/fao_trai... Wolf, P. (1984). Elementary Surveying (7th ed). Portland, Or.,Book News Inc. Field Work 01 Taping: Determining a horizontal distance in level ground and determining a horizontal distance in sloping ground Overview Taping is a common method of measuring or laying out horizontal distances. It consists of stretching the calibrated tape between two points and reading the distance as indicated on the tape. Objectives 1. To find the horizontal length of a line in level ground. 2. To find the horizontal distance between two points in sloping ground. Instruments 5 hubs 2 range poles 1 steel tape 1 plumb bob 3 chaining pins Procedure 1. Taping on Level Ground a. Mark in the level ground the endpoints A and B of the line to be measured. Use range poles to mark the end points. b. With the rear tapeman at the initial point and head tapeman moving forward with the zero end of the tape, measure directly the line AB using the tape. c. Measure the line AB at five times corresponding to five trials. d. Record each measurement made. e. Compute the most probable value (mpv) of the measured length AB. 2. Taping on Sloping Ground a. Mark in the sloping ground the endpoints C and D of the line to be measured. Use range poles to mark the end points. b. With the rear tapeman at the initial point C in the higher ground and the head tapeman moving downhill toward the endpoint D with the zero end of the tape, determine the horizontal distance CD using the "breaking tape" procedure. c. Determine the horizontal distance CD at five times corresponding to five trials. d. Record each measurement made. e. Compute the most probable value (mpv) of the measured horizontal distance CD. Field Work 02 Determining a horizontal distance by pacing Overview Pacing is a convenient means of determining an approximate horizontal distance. It can be used to roughly check a measurement done with a tape. A pace is a natural step. Objective To determine a horizontal distance by pacing Instruments 2 steel hubs Procedure 1. Pacing on Level Course a. Choose and mark endpoints A and B between a straight and level course whose length is known and recorded. b. Walk naturally from A to B (as in a trial) while counting the number of steps made. c. Record the number of steps as number of paces made from A to B. d. Perform the second and third steps in the procedure, four more times to have a record of five trials. e. Compute the pace factor. f. Mark the endpoints of an unknown distance as C and D whose distance is desired to be determined by pacing. g. Walk naturally from C to D while counting and recording the number of paces made. Make five trials. h. Compute the paced distance. Field Work No. 3 Survey with Tape Objectives 1. To determine obstructed or inaccessible horizontal distance between two points using survey with tape technique 2. To lay off an angle in the field using survey with tape technique Instruments 1 steel tape 7 hubs Procedure 1. Using an appropriate survey with tape technique find the obstructed horizontal distance between point A marked on ground at one side of the acacia tree and point B marked on ground at the other side of the acacia tree.. a. Submit the field computation with the accompanying sketch. 2. Using an appropriate survey with tape technique lay off a 32 degree angle with point C as its vertex and a designated existing line CE as one of its two sides. a. Submit a sketch (of the laid off angle showing the existing line CE), and the accompanying field computation. Field Work No. 4 Differential Leveling Objective To determine the elevation of points by differential leveling Instrument 1 level 1 leveling rod Procedure 1. Take and record a backsight at a designated BM- 1. 2. Take and record a foresight at an established TP-1. 3. Transfer and set up the level at a location beyond TP-1. 4. Take and record a backsight at TP-1. 5. Take and record a foresight at an established TP-2. 6. Transfer and set up the level at a location beyond TP-2. 7. Take and record a backsight at TP-2. 8. Take and record a foresight at BM-2. 9. Complete the tabulation required (See tabulation in Elem Surv https://facebook.com in "Notes") or see downloadable pdf file on differential leveling tabulation below. Fieldwork No. 5 Survey on the topography Objective to locate points of the same elevation Instruments 7 hubs 1 steel tape 1 level 1 leveling rod Procedure 1. Layout a square grid on the ground. 2. Mark each corner of each square in the grid. 3. Find and record the elevation of each corner of each square in the grid using appropriate leveling techniques. 4. Make a sketch of the square grid showing contour line connecting points of the same elevation. Reference Topographic surveys- direct levelling. (n.d.) ftp://ftp.fao.org/fi/cdrom/fao_trai... *************************** FOR DIFFERENTIAL LEVELING TABULATION, SEE DOWNLOADABLE PDF FILE BELOW.
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Elementary surveying in engineering and architecture Learning Schedule 1st Semester School Year 2017-2018 June 13- 16 Syllabus presentation, safety and use of surveying instrument June 20- 23 Horizontal distance measurement, relative precision, most probable value (mpv), pacing, pace factor, paced distance, stadia method, subtense bar method June 27- 30 Taping, aligning the tape, stretching the tape, plumbing, marking full tape length, tallying taped measurements, measuring fractional lengths, breaking tape procedure, slope taping and problem solving on slope taping computation using cosine function and using Pythagorean theorem July 4- 7 Surveys with tape, erecting perpendicular to line, chord bisection method, 3:4:5 method, measuring angles with tape, laying off angles with tape; determining obstructed distances by tape alone using indirect methods (in combination of two or more of tape survey techniques as appropriate) with application of principle of similarity of triangles, equality of ratios of corresponding sides of similar triangles, Pythagorean theorem, trigonometric functions, properties of rectangle, equiangular and equilateral triangles, and congruent triangles; problem solving examples involved in tape survey techniques which includes technique in determining obstructed or inaccessible distances July 11-14 Differential leveling and calculations, bench mark, turning point, backsight, foresight, height of the instrument, computation of elevation July18-21 Survey of topography, elevations, contour lines, profile July 25-28 Most probable value (mpv) of each of interior angle measurements for three sided closed traverse; mpv of each of three horizontal central angle measure-ments whose sum should equal to 360 degrees; mpv of each of three horizontal angles, the sum of the mpv of the two angles of which should equal to the mpv of the third angle August 1-4 Measurements of angles and directions; problem solving examples on finding the bearing of a line when the azimuth of the line is given, and problem solving example on determining the azimuths of a line when the bearing of the line is given; problem solving example involving magnetic declination; definition of terms as magnetic declination, magnetic meridian, true meridian, true north, magnetic north, and direction of line August 8-11 (Lessons review, refresher, and assessment) August 15-18 Hydrographic survey modeling and simulation, stream cross sectional area estimation, stream discharge computation; procedure for closed traverse survey September 5-8 Computation of interior angles, exterior angles, and deflection angles given the bearings (directions) of lines of closed traverse; computation of azimuths (directions) from north of a line using given bearings (directions) of lines, computation of linear error of closure after the closed traverse survey, latitudes, departures, bearing angle of side of error; traverse adjustment, perimeter of the traverse, correction to latitude, correction to departure, adjusted latitude, adjusted departure, adjusted bearing September 12-15 Subdivision, area computation, refresher lesson hydrographic survey, cross sectional area computation, stream discharge formula, triangulation, law of sines September 19-22 Softwares, systems, and programs in surveying, Surface-DTM, RoadDTM, Contour-DTM, TCP MDT Surveying, autoCAD, Microsoft Excel, Microsoft Word, Microsoft Powerpoint, C++, Python, Java, and web developing systems September 26-29 Adjustment of interior angles of the traverse, law of sines Refresher lesson Laboratory safety and safety on the use of laboratory equipment October 3-6 Review ************************************
continuation.. Fieldworks Field Work No. 6 Closed Compass Traversing Overview A closed compass traverse is a series of lines which forms a closed loop. Each line in the traverse has length and direction which have been determined from field measurements (La Putt, 1987). Surveys to be performed by traversing not requiring high degree of precision employ magnetic compass. The direction of a line is described using its bearing. A bearing that is observed in the direction in which the survey progresses is referred to as forward bearing. The bearing that is observed in the opposite direction is a back bearing. Objectives 1. To run a compass traverse 2. To establish angular relationships between lines in the traverse by deflection angles, interior angles, exterior angles, bearings and azimuths. Instrument 1 compass instrument 5 steel hubs 1 steel tape 1 plumb bob Procedure 1. Establish five traverse stations A, B, C, D and E. 2. Set and level the instrument at A. Release the needle screw. Sight on a point at the last traverse station. Observe and record the bearing. Sight at B. Read the magnetic bearing. Record the observation. 3. Transfer the instrument to B. Level the instrument. Sight at A. Observe and record the bearing. Turn toward the direction of C. Observe and record the magnetic bearing of line BC. 4. Transfer the instrument to C. Level the instrument. Sight at B. Read and record the observed bearing. Turn toward the direction of D. Read and record the bearing of line CD. 5. Proceed to the next station. Repeat the same procedure of reading and recording the bearing. Continue until the last traverse station is occupied. 6. Using taping, measure the length of each line of the traverse. Record all measurements. 7. Tabulate the values. Length Observed Bearings Line (meter) Forward Back AB ______ _________ _______ BC ______ _________ _______ CD ______ _________ _______ DE ______ _________ _______ EA ______ _________ _______ 8. Compute the azimuths, deflection angles, interior angles, and exterior angles to establish the angular relationship between the lines of the traverse. Reference La Putt, J. P. (1987). Elementary Surveying (3rd ed). Philippines: Baguio Research & Publishing Center. Fieldwork No. 7 Traverse Computations Overview The field measurements for a closed traverse should be investigated in relation to their consistency with the geometric properties of the figure formed by the traverse. When discrepancies are found, it is necessary to perform computations to correct and hence adjust the lengths and angles in the traverse. A method of adjustment will involve the calculation of latitudes and departures of the lines of the traverse. The magnitude of the latitude of a line in the traverse can be expressed as the product of the length of the line and the cosine of the bearing angle of the line, and is positive or negative for north line projection or south line projection, respectively. The magnitude of the departure of the line can be determined by multiplying the length of the line by the sine of the bearing angle of the line and is positive or negative for the east line projection or west line projection, respectively. The linear error of closure expresses the accumulated field measurement errors when running the traverse. Its length is computed by extracting the square root of the sum of the square of the algebraic sum of all latitudes of the lines in the traverse and the square of the algebraic sum of all departures of the lines in the traverse. The tangent of the bearing angle of the linear error of closure is the ratio of the negative of the algebraic sum of all departures to the negative of the algebraic sum of all latitudes of the lines of the traverse. Objectives 1. to determine the error of closure of a closed traverse 2. to express the relative precision in line with the closed traverse survey conducted Instrument 1 compass instrument or electronic survey instrument 5 steel hubs 1 steel tape Procedure 1. Ran a closed traverse survey (measure the lengths and directions of the lines of the closed traverse). 2. Determine the latitudes and departures of the lines of the traverse and their respective algebraic sums. 3. Calculate the total error of closure. 4. Determine the relative precision. 5. Use the tabulations below as necessary. Line length Bearing Latitude Departure (m) + (N) - (S) +(E) - (W) ____ _____ _______ _____ _____ _____ _____ _____ _____ _______ _____ _____ _____ _____ _____ _____ _______ _____ _____ ______ _____ _____ _____ _______ _____ _____ ______ _____ _____ _____ _______ _____ _____ ______ _____ Fieldwork No. 8 Control Survey by Triangulation Overview Before satellite positioning was available, the most common technique for conducting control surveys, was triangulation. Triangulation is used to extend control networks, point by point and triangle by triangle. It is a method that involves measurement of the angles and a distance in a triangle formed by three control points. The distance measured is known as baseline. The two other sides of the triangle are calculated. One calculated side is used to calculate distances to another point to start another triangle until a desired triangulation network is made. Objective to extend control networks by triangulation Instrument 1 compass instrument or electronic survey equipment 5 hubs 1 stadia rod Procedure 1. Establish station A as control point. Mark a point B away from A along a baseline. 2. Measure the azimuth from the north of the line. 3. Measure a baseline length. 4. Mark a point on the ground to form a triangle with a known distance as one of the sides. 5. Measure all interior angles in the triangle twice and record the mean interior angles. 6. Calculate the lengths of remaining sides. 7. Repeat Steps 3, 4, 5, 6, and 7 as necessary to establish new control points. |