# ELEMENTS OF CIVIL ENGINEERING Subject Code 2110004 Teaching

ELEMENTS OF CIVIL ENGINEERING (Subject Code - 2110004) Teaching Scheme Credits L 4 P 2 C 6 Examination Marks Theory Marks Total Practical Marks ESE PA (E) (M) Viva (V) (I) 70 30* 30# 20** Marks 150 L- Lectures; P- Practical; C- Credit; ESE- End Semester Examination; PA- Progressive Assessment Passing marks for ESE (E) will be 23 out of 70. Passing marks for PA (M) will be 12 out of 30. Passing marks for ESE Practical (V) will be 15 out of 30. Passing marks for PA (I) will be 10 out of 20. 1

Branches of Civil Engineering 1. Surveying 2. Construction Engineering 3. Transportation Engineering 4. Fluid Mechanics 5. Irrigation Engineering 6. Structural Engineering 7. Geotechnical Engineer 8. Foundation Engineering 9. Environmental Engineering 10. Quantity Surveying 11. Earthquake Engineering, etc. , 2

Definition of Surveying is one of the basic area in civil engineering which includes linear and angular measurement of the relative positions of the points on the surface of the earth. Or Surveying is the art and science of determining the relative positions of various points or stations on the surface of the earth by measuring the horizontal and vertical distances, angles and taking the details of these points and by preparing a map or plan to any suitable scale. Thus, in surveying, the measurements are taken in the horizontal and vertical planes. 3

Fundamental principles of surveying 1. To work from whole to part 2. To fix or to locate a new point or station by at least two independent measurements or processes whole to part to whole 4

Second Principle of Surveying • To fix or to locate a new point or station by at least two independent measurements or processes R . L 1 P R. P Q L 2 Q P R. α β Q 5

Aims of Surveying Or Purposes of Surveying Or Objects of Surveying • To prepare a map or plan to show the relative positions of the objects on the surface of the earth. • To fix the boundaries of districts, states and countries. • To Determine areas and volumes. • To layout or to mark the positions of the proposed structures on the ground. e. g. Building, Canal, Roads, Dams, Railway, Airports, etc. , 6

Applications of surveying Or Uses of Surveying • To prepare a topographical map which shows hills, valleys, rivers, forests, villages, towns etc. , • To Prepare a Cadastral map which shows the boundaries of fields, plots, houses and other properties. • To prepare contour map to know the topography of the area to find out the best possible site for dam, canals, buildings, roads, railways, bridges etc. , • Military survey is used for determining points of strategic importance, etc. , 7

Plan and Map 1. The graphical representation is 1. The graphical representation called a plan if the scale is large. is called a map if the scale is small. 2. A plan is drawn on a large scale. 2. A map is drawn on a small scale. 3. Scale 1 cm = 100 m or > 100 m 3. Scale 1 cm = 10 m or < 10 m 4. On a plan, generally horizontal 4. On a topographic map, vertical distances and directions are distances (Elevations) are also shown by contour lines. shown. 5. A plan is drawn for small area. 5. A map is drawn for large area. e. g. – map of Gujarat e. g. – plan of house – map of India – plan of bridge 8

Primary Divisions of Surveying • 1. Plane Surveying • 2. Geodetic Surveying 9

Differentiate between Plane surveying and Geodetic Surveying Plane Surveying Geodetic Surveying 1. The earth surface is considered as a plane surface, a curved surface, i. e. curvature of the earth is ignored. considered. 2. This survey is done for smaller 2. This survey is done for large area less than 250 Km 2 (< 250 Km 2 greater than 250 Km 2 (>250 Km 2) ) 3. High accuracy required. 3. Comparetively low accuracy required. 4. The line joining any two stations is considered as a curved line. considered to be straight. 5. The triangle formed by any three points is considered as a spherical. points is considered as a plane. 6. This Survey is carried out by the 6. This Survey is not carried out by survey of India department. 10

Classification of Surveying Based on………… • Based on instruments • Based on Purpose (Object) • Based on method • Based on Nature of field • Based on Primary Divisions 11

Classification of Surveying Based on instruments 1. Chain Survey 2. Compass Survey 3. Chain and Compass Survey 4. Plane Table Survey 5. Theodolite Survey 6. Tacheometry Survey 7. Levelling Survey 8. Photographic and aerial Survey 9. EDM Survey 10. Remote Sensing 12

Classification of Surveying Based on Purpose (Object) 1. Geological Survey 2. Mine Survey 3. Archaeological Survey 4. Military Survey 5. Control Survey 6. Topographical Survey 7. Cadastral Survey 8. Route Survey 9. Engineering Survey 10. Construction Survey 13

Classification of Surveying Based on method 1. Triangulation Surveying – The entire area is divided into a network of triangles 2. Traversing – A traverse is a circuit of survey lines. It may be opened or closed. When the linear measurements are done with a chain & a tape and the directions or horizontal angles are measured with a compass or a theodolite respectively is called traversing. 14

Classification of Surveying Based on Nature of field 1. 2. 3. 4. Land Survey Hydrographic Survey Astronomic Survey Arial Survey 15

Classification of Surveying Based on Primary Divisions • 1. Plane Surveying • 2. Geodetic Surveying 16

R. F. (Representative Fraction) Distance on Plan or Map R. F. = Corresponding Distance on Ground Example : Scale is 1 cm = 5 m find R. F. ? R. F. (Representative Fraction) = = = . ˙. R. F. = 1 : 500 17

Examples 18

An area of 58 cm 2 of a map represents an area of 4698 m 2 what is R. F. ? 58 cm 2 = 4698 m 2. ˙. 1 cm 2 = 4698 / 58 m 2. ˙. 1 cm = 81 m. ˙. 1 cm = 9 m 1 cm R. F. (Representative Fraction) = = 9 m 900 cm = 1 900 Solution: . ˙. R. F. = 1 : 900 19

10, 000 1 hectares = ______ m 2 4046. 94 1 acre = ______ m 2 1. 6093 1 mile = ______ km 20

A plan represents an area of 7. 5 Hectares and measures 3 cm x 5 cm, Find the scale of the map and R. F. Solution: 7. 5 Hectares = (3 x 5) cm 2 10, 000 Now, 1 hectares = ______ m 2. ˙. 7. 5 x 10000 m 2 = 15 cm 2. ˙. 15 cm 2 = 75000 m 2. ˙. 1 cm 2 = ______ m 2 5000. ˙. 1 cm = 5000 m 2 70. 71. ˙. Scale 1 cm = ______ m R. F. (Representative Fraction) = . ˙. R. F. = 1 : 7071 = 1 cm 70. 71 m 7071 cm 1 7071 21

Scale : • Scale is the basic requirement for the preparation of Plans or Maps. • Scale is used to represent large distance on paper. • If the scale of the Map is 1 cm = 10 m it means that 1 cm on paper represents 10 m on the ground. 22

Types of Scale : 1. 2. 3. 4. Plain Scale Diagonal Scale Chord Scale Vernier Scale 23

Example : 1 • Construct a Plain Scale of R. F. 1/500 to measure up to a meter and represent 37 m on the scale. R. F. = 1 500 . ˙. 1 cm = 500 cm. ˙. 1 cm = 5 m. ˙. 5 m 1 cm 10 m ? = 2 cm. ˙. Draw 2 cm = 10 m Then, 2 cm Divide in 10 Divisions. ˙. 2 mm = 1 m Then, Draw figure…. 24

Example : 2 • Construct a Plain Scale 1 cm = 2 m and show on it 12 m. Solution : 2 m 1 cm 10 m ? = 5 cm. ˙. Draw 5 cm = 10 m Then, 5 cm Divide in 10 Divisions. ˙. 5 mm = 1 m Then, Draw figure……… 25

Example : 3 • Construct a Diagonal Scale 1 cm = 5 m and show on it 45. 3 m. Solution : 5 m 1 cm 10 m ? = 2 cm. ˙. Draw 2 cm = 10 m Then, 2 cm Divide in 10 Divisions. ˙. 2 mm = 1 m Then, Draw figure……… 26

Plain Scale: • A Plain scale is one on which it is possible to measure two dimensions only. • For Example, Meters and Decimeters, (1 m and 0. 1 m) Hundreds and Tenths, (100 and 10) Units and Tenths, etc. , (1 and 10) 27

Diagonal Scale: • A Diagonal scale is one on which it is possible to measure three dimensions. • For Example, Meters, Decimeters and Centimeters (1 m, 0. 1 m and 0. 01 m) Units, Tenths and Hundreds (1, 10 and 100) 28

Classification of Scale: • Large Scale : 1 cm = 10 m or Less than 10 m (< 10 m) • Medium Scale : 1 cm = 10 m to 100 m • Small Scale : 1 cm = 100 m or more than 100 m (> 100 m) 29

Linear measurements • Linear Measurements are carried out for finding out measurements in horizontal plane. Methods : 1. Direct methods 2. Optical methods 3. E. D. M. methods (E. D. M = Electromagnetic Distance Measuring instrument ) Or (Method Based on Electronics) 30

In Methods of Direct Measurements • Chaining – Chaining is used to measure horizontal distance either by a chain or a tape. Ø Instruments Used in Chaining 1. Chain or Tape 2. Arrows 3. Pegs 4. Ranging Rods 5. Plumb Bob 31

Fig. Arrow 32

Types of Tapes : 1. Cloth Tape 2. Fiber Glass Tape 3. Metallic Tape 4. Steel Tape 5. Invar Tape : – 36 % Nickel & 64 % Steel. – It is not affected by change of Temperature. – It is Very Accurate. 33

Operations in Chain Surveying 1. Chaining 2. Ranging 3. Offsetting 34

1. Chaining A. Chaining on Level Ground B. Chaining on Sloping Ground 35

A. Chaining on Level Ground 1. 2. 3. 4. 5. Fixing the Stations Unfolding the Chain Ranging Measuring the distance (Survey Lines) Folding the Chain B. Chaining on Sloping Ground 1. Direct Method 2. Indirect Method – 1) Method – I 2) Method – II, etc. , 36

2. Ranging : • The Process of locating or establishing intermediate points on a straight line between two survey stations or between the two fixed points in the field is known as Ranging. Or • The Process of establishing intermediate points on a straight line between two survey stations in the field is known as Ranging. Or 37

Or • If the distance to be measured between two survey stations is less than one chain the distance can be measured directly, but if the length of the survey line is greater than one chain length, intermediate points are to be located, in order that the chain is pulled along a straight line. The Method of locating or establishing intermediate points on a straight line between two survey stations or between the two fixed points in the field is known as Ranging. 38

2. Ranging A. Direct Ranging B. Indirect Ranging Or Reciprocal Ranging 39

A. Direct Ranging i. Ranging by eye ii. Ranging by line Ranger Fig…… B. Indirect Ranging Or Reciprocal Ranging Fig…. . 40

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Ranging by eye 43

Line Ranger 44

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Indirect Ranging Or Reciprocal Ranging 46

3. Offsetting or Offset : • Distances are measured from the survey lines to the object right or left of the survey line are called as offsets. A. Perpendicular Offsets B. Oblique Offsets C. Long Offsets ≥ 15 m D. Short Offsets < 15 m E. Swing Offsets – Offset taken by Swinging tape is called swing offset. It is one kind of Perpendicular Offset. 47

Fig. Perpendicular - Offset-by-Swinging 48

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Instruments used for laying offsets : 1. Optical Square i. Round Optical Square ii. Indian Optical Square 2. Prism Square 3. Cross Staff i. iii. iv. Open Cross Staff French Cross Staff Simple Cross Staff (Wooden) Adjustable Cross Staff 51

Round Optical Square Or Optical-Square-Circular 52

Indian Optical Square 53

• Fig. Prism Square 54

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Open Cross Staff 57

Open Cross Staff 58

Open Cross Staff with Rod 59

French Cross Staff 45° and 90° 60

Simple Cross Staff (Wooden) 61

Simple Cross Staff (Wooden) 62

Simple Cross Staff (Wooden) with Stand 63

Adjustable Cross Staff 64

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Main Line, Base Line Check Line & Tie Line 67

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Selection of Survey Stations The Following points should be considered while selecting survey stations. 1. The station should be intervisible. 2. Survey lines should be minimum as far as possible. 3. Station should form well conditioned triangles. – (Interior angles not less than 30° and not more than 120°) 4. Station point should be located that tie lines, check lines, base line, etc. can be formed. 5. Station points should be selected within the boundary of the area to be surveyed. 6. The survey lines should be taken through fairly level 70 ground as far as practicable.

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