INTRODUCTION TO SURVEYING INSTRUMENTS

Transcription

1 PRACTICAL: 1 INTRODUCTION TO SURVEYING INSTRUMENTS

2 1. INTRODUCTION TO SURVEYING INSTRUMENTS Object: To study various Surveying Instruments a) Instruments Used for Linear Measurements Chain or Tape Arrows Pegs Ranging Rods Offset Rods Plumb Bob Optical Square Line Ranger b) Instruments Used in Angular Measurements Prismatic Compass Surveyors Compass c) Instruments Used in Vertical Measurements Leveling Staff Dumpy Level Theodolite d) Instruments Used for Measurement of area. Planimeter

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9 CONCLUSION: ASSIGNMENT: Q1) Enlist uses of above mentioned Surveying Instruments: GRADE: SIGNATURE:

10 PRACTICAL: 2 CHAINING AND OFFSET TAKING

11 CHAINAGE DIAGRAM

12 2. CHAINING AND OFFSET TAKING OBJECT: To measure horizontal distance between two points by chaining and to take perpendicular offsets INSTRUMENTS: Metric Chain, Tape, Ranging rods, Arrows, Cross Staff, Line PROCEDURE: ranger, Optical Square. Two chain men are required in this process. The chain men are called as Leader and follower. The chain man at the forward end of the chain is called leader and chain man at the zero or rear end of the chain is called as follower. Fix station A and B at some distance by fixing wooden peg to determine horizontal distance between them. Position of station A, and B is fixed by measuring their position from at least three permanent objects and location sketch of station A and b are drawn. The follower holds one handle of the chain in contact with peg at station A. The leader takes the other handle of the chain, arrows and ranging rod & walks in the forward direction dragging chain with him. After the chain is stretched completely along the line the follower steps on one side of the line with the ranging rod touching the handle. The follower directs the leader to stand exactly in the line. The leader puts a scratch at the position & inserts an arrow. He then moves forward with the chain handle with the remaining arrows and ranging rod till the follower reaches the next arrow point.

13 STATION A LOCATION SKETCH STATION B LOCATION SKETCH

14 During this procedure details which are along the side of the chain line are located by lateral measurement with the help of offset and tape. The points located are known as perpendicular offsets. All the perpendicular offsets are measured till station B is reached. All the measurements recorded in the field book. CONCLUSION: ASSIGNMENT: Q1).Explain various sources and nature of errors in chain surveying. GRADE: SIGNATURE:

15 PRACTICAL: 3 COMPASS SURVEY

16 3. COMPASS SURVEY OBJECT: Study of Prismatic Compass & to determine fore and back bearing of survey line AB, BC, CA Included Angles. INSTRUMENTS: Tripod, Prismatic Compass, Ranging rods, Measuring Tapes, Wooden Pegs, Hammer. THEORY: Fore Bearing: The bearing of a line measured in the direction of progress of survey is called fore bearing. Back Bearing: The bearing of a line measured in the opposite direction of progress of survey is called fore bearing. PROCEDURE: TEMPORARY ADJUSTMENTS OF A PRISMATIC COMPASS The Prismatic Compass is set up at a point say station A. The following temporary adjustments are needed to be carried out at each set Up of Instrument Centering: Centering is the process of keeping the instrument exactly over the station. It is carried out by dropping a piece of stone so that it falls on the top of the pegs fixed at station point. Leveling: Prismatic compass is leveled by means of ball and socket arrangement so that the graduated ring may swing freely.

17 Focusing the prism: The reflecting prism is adjusted to the eye sight of the observer by rising or lowering then stud until the graduations are seen sharp and clear. CALCULATION OF FORE AND BACK BEARING Suppose the bearing of line AB, BC, CA of a triangle is to be observed. Set up the instrument at station A and carry out all the temporary adjustments. Fix the ranging rod at B. Turn the prismatic compass until the ranging rod at station B is bisected by the horse hair when seen through the vertical slit above the prism. When the needle comes to rest bisect ranging rod at B exactly and note the reading. The reading observed is the Fore bearing of line AB i.e. Angle measured with respect to north. Now shift the prismatic compass at station B perform all temporary adjustments and from station B bisect station A towards backward, the reading observed in prismatic compass is the Back Bearing of line AB. Now from the same setup of the instrument Bisect station C and note down the reading of prismatic compass as fore bearing of line BC. Transfer the instrument to station C to obtain back bearing of line BC. Similarly observe Fore Bearing and back bearing of line CA. Check the Difference of Fore bearing and back bearing of each line it should be equal to 180 0

18 N B N FB BB A C OBSERVATION TABLE STATION LINE LENGTH F.B B.B DIFFERENCE ANGLE CORRECTION CORRECTED ANGLE CALCULATION:

19 TO FIND INCLUDED ANGLES Included Angles of a triangle are calculated from observed FB and BB of line AB,BC,CA Included angle is determined by following formula = Back Bearing of Previous Line- Fore Bearing of next line i.e. for triangle ABC A= BB of CA FB of AB B=BB of AB FB of BC C=BB of BC FB of CA Check: Sum of all included angles Should be Equal to (2n-4) x 90 0 CONCLUSION: ASSIGNMENT: Q1).What is local attraction? How it is detected? GRADE: SIGNATURE:

20 PRACTICAL: 4 SIMPLE LEVELLING

21 OBSERVATION TABLE STATION B.S I.S F.S RISE FALL R.L. REMARK B.S. - F.S. = RISE- FALL= LAST R.L. FIRST R.L.= Check: - B.S. - F.S. = Rise- fall= Last R.L. First R.L. CALCULATION:

22 4. SIMPLE LEVELLING OBJECT: To find reduced level of various points by simple leveling. INSTRUMENT: Dumpy level, Tripod, leveling staff, pegs, Hammer PROCEDURE: Simple leveling: - It is the simplest method of leveling used, when it is required to find the difference in elevation between 2 points. TEMPORARY ADJUSTMENT OF DUMPY LEVEL: The Dumpy Level is fixed on the tripod at station say O. Setting up the level The tripod legs are adjusted at a convenient height. Any two legs of the tripod are fixed on the ground by pressing the tripod into the ground. The movement of the third leg is made in such a way that the bubble remains in the center. Leveling The actual leveling is then done by moving foot screw on the leveling head. Instrument s telescope is kept Parallel to two foot screws and both the foot screws are either moved inward or outward till the longitudinal bubbles is in the centre of its run. The telescope is then turned through 90 0 so that the telescope is now parallel to third foot screw. Now move third screw inward or outward till bubble is in center. Then the telescope is brought in its original position. The procedure is carried out till the bubble remains in the center in both the position.

23 OBSERVATION TABLE STATION B.S I.S F.S H.I R.L. REMARK B.S. - F.S= LAST R.L. FIRST R.L= CHECK: - B.S. - F.S. = RISE- FALL= LAST R.L. FIRST R.L. CALCULATION:

24 Removal of parallax Focusing the eye piece To focus so that the cross hairs for distinct vision hold a sheet of white paper in front of objective glass, and move the eye piece till the image of cross hair are seen distinct and sharp. Focusing of objective glass The telescope is then directed towards the staff held vertically at bench mark (B.M.) say station A and by turning the focusing screw. Parallax is removed by moving focusing screw till the image of staff is seen distinct and clear. HEIGHT OF INSTRUMENT METHOD In this method the height of instrument is calculated for each setting by adding Back sight to the elevation of bench mark i.e. = Reduced Level (R.L.) of B.M. + B.S. The R.L. of Intermediate points is calculated by subtracting the HI- IS (Intermediate sight). The process is continued till the R.L. of last point is obtained by subtracting the staff reading from height of last setting of instrument. i.e. HI FS Apply the arithmetic check to verify the calculation by height of Instrument

25 RISE & FALL METHOD In rise & fall method, the height of Instrument is not at all calculated but the difference of level between consecutive points is found by comparing the staff readings on the two points for the same setting of the instrument. Rise and fall is calculated using following formula. BS-IS or BS-FS if +ve then Rise and if BS-IS or BS-FS is ve then fall i.e. If the reading is positive then it is rise and if the reading is negative then the reading is called fall. The figure for rise & fall worked out thus for all the points give the vertical distance of each point above or below the preceding one, and if the level of any one point is known then the level of the next will be obtained by adding its rise or subtracting its fall, as the case may be. CONCLUSION: ASSIGNMENT: Q1).What are the different types of leveling? GRADE: SIGNATURE:

26 PRACTICAL: 5 DIFFERENTIAL LEVELLING

27 5. DIFFERENTIAL LEVELLING OBJECT: To find difference of elevation between two points (too far away) by differential leveling. INSTRUMENTS: Dumpy Level, tripod, Leveling staff, pegs, etc. PROCEDURE: The Operation of leveling to determine the elevation of points at some distance apart is called differential leveling. When two points are at such a distance from each other that they cannot both be within range of the level at the same time, the difference in elevation is not found by single setting but the distance between the points is divided in stages by change points on which the staff is held and the difference of elevation of each of succeeding pair of such change points is found by separate setting up of the level. TEMPORARY ADJUSTMENT OF DUMPY LEVEL: The Dumpy Level is fixed on the tripod at station say O. Setting up the level The tripod legs are adjusted at a convenient height. Any two legs of the tripod are fixed on the ground by pressing the tripod into the ground. The movement of the third leg is made in such a way that the bubble remains in the center.

28 OBSERVATION TABLE STATION B.S I.S F.S H.I R.L. REMARK B.S. - F.S= LAST R.L. FIRST R.L= CHECK: - B.S. - F.S. = RISE- FALL= LAST R.L. FIRST R.L. CALCULATION:

29 Leveling The actual leveling is then done by moving foot screw on the leveling head. Instrument s telescope is kept Parallel to two foot screws and both the foot screws are either moved inward or outward till the longitudinal bubbles is in the centre of its run. The telescope is then turned through 90 0 so that the telescope is now parallel to third foot screw. Now move third screw inward or outward till bubble is in center. Then the telescope is brought in its original position. The procedure is carried out till the bubble remains in the center in both the position. HEIGHT OF INSTRUMENT METHOD: In this method the height of instrument is calculated for each setting by adding Back sight to the elevation of bench mark i.e. = Reduced Level (R.L.) of B.M. + B.S. The R.L. of Intermediate points is calculated by subtracting the HI- IS (Intermediate sight). The elevation of change points (CP) is calculated by subtracting the HI- FS (Fore sight). For next setting of the instrument, the H.I. is obtained by adding the B.S and R.L. of change point i.e. BS + RL (CP) The process is continued till the R.L. of last point is obtained by subtracting the staff reading from height of last setting of instrument. i.e. HI FS Apply the arithmetic check to verify the calculation by height of Instrument

30 OBSERVATION TABLE STATION B.S I.S F.S RISE FALL R.L. REMARK B.S. - F.S. = RISE- FALL= LAST R.L. FIRST R.L.= CHECK: - B.S. - F.S. = RISE- FALL= LAST R.L. FIRST R.L. CALCULATION:

31 RISE & FALL METHOD: In rise & fall method, the height of Instrument is not at all calculated but the difference of level between consecutive points is found by comparing the staff readings on the two points for the same setting of the instrument. Rise and fall is calculated using following formula. BS-IS or BS-FS if +ve then Rise and if BS-IS or BS-FS is ve then fall i.e. If the reading is positive then it is rise and if the reading is negative then the reading is called fall. Rise & fall worked out thus for all the points give the vertical distance of each point above or below the preceding one, and if the level of any one point is known then the level of the next will be obtained by adding its rise or subtracting its fall, as the case may be. CONCLUSION: ASSIGNMENT: Q1) Explain Reciprocal Leveling? GRADE: SIGNATURE:

32 PRACTICAL: 6 STUDY OF THEODOLITE

33 6. STUDY OF THEODOLITE OBJECT: To Study different components of Theodolite INSTRUMENT: Theodolite THEORY: The theodolite is an instrument designed for the measurement of horizontal and vertical angles. Theodolite is the most precise instrument; it is also used for laying off horizontal angles, locating points on the line, prolonging the survey lines, establishing grades, determination of difference of elevation setting out curves, observation of bearings etc. TYPES OF THEODOLITE The theodolites may be primarily of two types: Transit Theodolite Non Transit Theodolite In a transit theodolite the telescope can be revolved through a complete revolution about its horizontal axis in a vertical plane. In non transit theodolite, the telescope is mounted in such a manner that the line of sight cannot be reversed by revolving the telescope. COMPONENTS PARTS OF A THEODOLITE: Leveling head: It supports the main working parts of the instrument and screw on the tripod. The head comprises of two parts: Leveling base or tribrach fitted with leveling foot screws for leveling the instrument.

34 Movable head or centering arrangement for centering the vertical axis accurately over the station. Lower circular horizontal metal plate: It carries a circular graduated arc. It is silvered and graduated from 0 0 to in a clock wise direction. Upper circular horizontal metal plate: The upper plate carries an index and vernier to Read fine reading on the graduated horizontal circle. Telescope: Fitted to a horizontal axis, it consists of eye piece and diaphragm at one end and objective glass at the other end. The telescope has focusing screw by which any Object can be bisected. Circular graduated arc on a vertical circle: It is attached to the horizontal axis of the telescope. It is usually divided into 4 quadrants, but in some instruments it is graduated from 0 0 to the sub divisions of the vertical circle are similar to those of horizontal circle. Vernier frame: carrying an index and verniers to measure vertical angles. Lower clamp and lower tangent screw: A lower clamp, clamps the lower plate and the lower tangent screw enables finely controlled circular motion of lower plate. Upper clamp and upper tangent screw: An upper clamp, clamps the upper plate to lower one, and the upper tangent screw enables finely controlled circular motion about vertical axis Vertical circle clamp and tangent screw: A vertical circle clamp, clamps the vertical circle and its tangent screw enables a finely controlled circular movement to be given to the combined telescope and vertical circle about the horizontal axis. Circular level: It is located on the top of tribrach Plate level: It consist of plate bubble, which keeps the instrument parallel to horizontal axis.

35 Compass: A circular or trough compass may be mounted on the vernier plate between the standards for observing bearings. Tripod: Theodolite is mounted and fixed on the tripod for each set up. As tripod has adjustable legs, theodolite can roughly leveled with the adjusting the legs of tripod CONCLUSION: ASSIGNMENT: Q1).What is the difference between transit and non-transit Theodolite? GRADE: SIGNATURE:

36 PRACTICAL: 7 STUDY OF PLANIMETER

37 PLANIMETER

38 7. STUDY OF PLANIMETER OBJECT: To Study Planimeter and to find constants of the Planimeter. THEORY: A Planimeter is used by engineers for measuring area of any figure which has been plotted to scale particularly when the boundaries are irregular or curved. Planimeter is largely used for finding the area of contours in determining the capacity of storage reservoirs. CONSTRUCTION OF PLANIMETER: The Planimeter consists of two arms, the tracing arm and anchor arm. The tracing arm is of adjustable length and has a tracing point which is moved round the periphery of the area to be measured. The amount by which tracing arm is moved is known on the wheel or roller which has its axis parallel to the tracing arm. The wheel has a roller divided into 100 equal parts and 1/100 th of drum division is read from the vernier having graduations from 0 to 9. The complete revolution of the wheel is recorded from 0 to 9. While taking the reading on the planimeter, the reading will be in 4 digits. Let the reading be The 1 st digit (4) is read on the disc. The second digit (3) is read on the rolling wheel (main scale). The third digit (7) is read on the rolling wheel (main scale). And the last digit (5) is read on the vernier scale besides the main scale of rolling wheel. Setting of tracing arm: The setting arm has calibrations on it and which facilitates the setting of tracing arm to given scale of the plan or map.

39 The adjustment which is to be made on the tracing arm as per scale of figure is given by the manufacturer. The multiplying and additive constants are also provided by manufacturer. While rotating the tracing arm round the periphery of the plan, the anchor point may be kept inside or outside the plan depending on the size of the figure. For large area the anchor arm is kept inside the figure for small area the anchor arm is placed outside the area. PROCEDURE: Make the adjustments of the tracing arm as per scale of the plan. The anchor is placed inside or outside of figure such that the tracing point can be conveniently moved on the periphery of the plan. Any point on the periphery of the plan can be taken as the starting point and from where the tracing point moves along the periphery and closes back. Before the start of tracing work the initial reading (I.R) is recorded and the final reading (F.R) at the end of tracing is noted down. While moving the tracing point around the periphery it is necessary to note down the number of times the zero of the counting disc has passed the fixed index mark in clock wise (+ve) and anticlockwise (-ve) directions Compute the area by using the formula: A=M (F.R I.R ±10 N +C)

40 Where, A= Area of the plan to be computed. M=Multiplying constant. F.R= Final reading on the disc. I.R=Initial reading on the disc. N= No of times the zero mark of the dial or disc crosses the fixed index mark.positive sign should be used if in clockwise and negative sign if it crosses in anticlockwise direction. C= Constant to be added if the anchor point is inside the plan of figure. C=0, if the anchor point is outside the figure.

41 OBSERVATION TABLE WHEN ANCHOR POINT IS OUTSIDE THE FIGURE WHEN ANCHOR POINT IS INSIDE THE FIGURE SNO. I.R F.R N M SNO. I.R F.R N M CALCULATION: RESULT: M= C=

42 CONCLUSION: ASSIGNMENT: Q1) what is meant by zero circle? Describe various methods of determining it area. GRADE: SIGNATURE:

43 PRACTICAL: 8 PAVEMENT MATERIALS & TRAFFIC CONTROL DEVICES

44 RIGID PAVEMENT FLEXIBLE PAVEMENT

45 8. PAVEMENT MATERIALS & TRAFFIC CONTROL DEVICES OBJECT: Study of Pavement Materials & Traffic Control Devices THEORY: Pavement: A Road pavement is a structure consisting of one or more layers of material which may be in natural form or it may be processed. The main function of the pavement is to distribute the loads coming on to it. Road pavements are generally of more than one layer and each layer is made up of suitable material, each layer is properly treated, compacted and placed one above the other. FUNCTION OF VARIOUS PAVEMENT LAYERS ARE AS FOLLOWS Wearing surface: This is the topmost layer; it comes in direct contact with the traffic. The function of wearing surface is to resist wear and tear and to avoid skidding of vehicles. Base: Base gives support to wearing surface. It distributes the concentrated loads from the upper layer to lower layers. Sub base: This is the intermediate layer acting as a cushion between the pavements. Sub grade: It is the bottom most layer forming the foundation for the road pavement. It is made of natural soil and carries the entire load of the traffic. TYPES OF ROAD PAVEMENT: Flexible Pavement: The earthen, gravel, water bound macadam and bituminous roads are known as flexible pavements because the top surface takes the shape of the sub surface soil. Rigid pavements: Cement Concrete roads are known as rigid pavements because of their stiffness and their capacity to bridge over loose soil pockets in the sub grade. Due to stiffness and thickness, there are no undulations on concrete roads.

46 TRAFFIC MARKINGS

47 PAVEMENT MATERIALS: Soil Stone aggregate Bituminous material Cement Soil: The soil is generally divided into 4 parts based on the particle size Larger than 2 mm Gravel Between 2 mm 0.06 mm - sand Between mm silt Smaller than clay Soil is very essential pavement material as behavior of pavement depends to a greater extent on the sub grade soil. Stone aggregate: Aggregates are the prime material used in pavement construction and they form the major portion of pavement structure. Aggregate are classified as per size as Fine aggregate Course aggregate Bituminous material: Bituminous construction works as binder Various bituminous materials used classified as: material are used in pavement in highway construction may be Bitumen Asphalt Tar Cutback Emulsion Cement: Cement is used as a binding material in rigid pavements

48 TRAFFIC CONTROL DEVICES: The various aids and devices used to control, regulate and guide traffic is called traffic control devices. The most common traffic control devices are Traffic signs Traffic signals Markings Islands

49 TRAFFIC MARKINGS

50 MANDATORY SIGNS

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52 CAUTIONARY SIGNS

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54 INFORMATORY SIGNS

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56 CONCLUSION: ASSIGNMENT: Q1).What are the different modes of transportation? GRADE: SIGNATURE:

57 PRACTICAL: 9 BUILDING COMPONENTS

58 9. BUILDING COMPONENTS OBJECT: to draw different building components (In a Separate Sheet) Brick WALLS: Stone masonry wall Brick masonry wall R.C.C LINTEL WITH CHHAJJA WALL FOUNDATION COLUMN FOUNDATION DOORS Fully paneled door Fully Glazed door DRAW THE SYMBOLS OF COMMON BUILDING MATERIAL Concrete Stone Wood Earth Glass Metal Plaster

59 CONCLUSION: ASSIGNMENT: Q1) Explain Substructure and Superstructure of a building? GRADE: SIGNATURE:

60 PRACTICAL: 10 DESIGNING A SIMPLE RESIDENTIAL BUILDING.

61 10. DESIGNING A SIMPLE RESIDENTIAL BUILDING. OBJECT: To Design a 2BHK residential building based on the various aspects of planning. Bed room Kitchen Drawing room Bath WC Bed room Verandah INSTRUCTIONS: All external walls are 30 cm thick All internal walls are 20 cm thick Walls of bath and W.C are 10 cm thick Locate doors and windows as per the requirement Draw plan, section, elevation, and schedule of doors and windows for the given line plan. Assume suitable dimensions (Draw in a separate sheet)

62 CONCLUSION: ASSIGNMENT: Q1).Explain various Principles of planning? GRADE: SIGNATURE:

63 PRACTICAL: 11 SITE VISIT

64 11. SITE VISIT OBJECT: Construction site visit to study various building materials. LOCATION: DESCRIPTION OF MATERIAL Cement Steel Bricks Type: Manufacturer: Average Daily consumption: Rate: Storage: Type: Manufacturer: Average Daily consumption: Rate: Storage: Treatment for protection: Type: Size: Quality Testing: Name of test carried out at site: Rate: Average daily consumption: Storage:

65 Aggregates Coarse aggregate Source: Dealer: Type: Size: Rate: Fine aggregate Source: Dealer: Type: Size: Rate: Concrete information: Grade: Cement Content: Method of Mixing: Workability: Production Capacity: Method of transportation: Compaction: Method of curing: Instruments used at site:

66 CONCLUSION: ASSIGNMENT: Q1).What is D.S.R? Where it can be procured? GRADE: SIGNATURE:

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