CIVL 335 Surveying Chapter 1 Part 1 - Introduction to Surveying Mwafag Ghanma, Ph.D. Geomatics Engineering Chapter 1 Part 1 - Introduction to Surveying Definition for Surveying In short, SURVEYING: • Science, art, and technology of determining the relative positions of points above, on, or beneath the earth’s surface. • A discipline which includes all methods for measuring and collecting information about the physical earth and our environment, processing that information, and distributing a variety of resulting products to a wide range of clients. Surveying for Engineers – Dr. Mwafag Ghanma 3 What do we do in SURVEYING? • Earth measurements: • Distances: horizontal, slope, and vertical • Angles: horizontal, vertical, and zenith • Determination of relative position of points located on, above or below the Earth’s surface: • Determination of the position is achieved by mathematical processing of the field measurements • Final output is positional information: • Maps: digital or paper • Coordinates • Features Surveying for Engineers – Dr. Mwafag Ghanma 4 Why Surveying is Important to CE • The planning and design of all Civil Engineering projects such as construction of highways, bridges, tunnels, dams etc. are based upon surveying measurements. • Moreover, during execution, project of any magnitude is constructed along the lines and points established by surveying. • Thus, surveying is a basic requirement for all Civil Engineering projects. Surveying for Engineers – Dr. Mwafag Ghanma 5 Why Surveying is Important to CE Surveying for Engineers – Dr. Mwafag Ghanma 6 Types of Surveying • Land, Boundary and Cadastral Surveying Deals with demarcating and mapping property boundaries and rights of land • Construction and Route Surveying Are surveying works for planning, design, implementation, and monitoring of construction projects such as roads, buildings, bridges, communication and infrastructure networks, etc. • Quantity Surveying Field works and computations related to determination of project quantities such as earth works (cut and fill), building materials, etc. • Plane Surveying (our course) Surveying suitable for projects occupying small areas i.e., where earth curvature can be (and is) ignored or neglected. • Geodetic Surveying Part of geodesy (study and representation of size and shape of the earth). This surveying deals with projects occupying large areas i.e., earth curvature is considered. • Topographic Surveying Deals with determining locations and elevations of natural and artificial features on the ground. This surveying is for making maps. Surveying for Engineers – Dr. Mwafag Ghanma 7 Course Organization and Contents • Basics of Surveying • • • • Arithmetic and Measurements: percentages, ratio and proportion. Geometry: angles types, polygons, triangles, circles. Angles in surveying: bearing and azimuth of a line. Theory of Errors: definitions, types and sources of errors, measures of precision. • Measurements and Field Practice • Distance measurement (slope, horizontal and vertical) using tapes, electronic distance measurement instruments, and leveling and errors in such measurements. • Direction and angle measurement using theodolites and total stations. • Applications • Topographic Surveying and Mapping: Contour lines and their characteristics, construction of contour maps, interpreting contour maps. • Traversing: uses, open and closed traverses, latitudes and departures, errors of closure and corrections. • Areas and Volumes: area of traverse, profile, cross-section using different methods, volumes of earthworks using grids or contour maps. Surveying for Engineers – Dr. Mwafag Ghanma 8 Lecture Notes Table of Contents Chapter 1: Part 1 - Introduction to Surveying Chapter 1: Part 2 - Basic Surveying Math Chapter 2: Basics of Surveying Chapter 3: Distance Measurement Quiz 1 (15%) Chapter 4: Leveling Midterm (20%) Chapter 5: Leveling Applications: Profiles and Cross-Sections Chapter 6: Leveling Applications: Contouring Quiz 2 (15%) Chapter 7: Control Surveying Applications: Traversing Chapter 8: Surveying Applications: Areas and Volumes Final (30%) Fieldwork & Reports = 15% + Lab Final Exam = 5% Surveying for Engineers – Dr. Mwafag Ghanma 9 Lecture Notes Surveying for Engineers – Dr. Mwafag Ghanma 10 Textbook and References Any other book in surveying will do! Surveying for Engineers – Dr. Mwafag Ghanma 11 Chapter 1 Part 2 - Basic Surveying Math Subjects • Percentages • The Pythagorean Theorem • Ratio and proportion • Types of Angles • Polygons • Triangles • Rectangles and squares • Trapezoids • Circles and length of arc • Perimeter • Solution of oblique triangles Surveying for Engineers – Dr. Mwafag Ghanma 13 Percentages The word "percent" comes from a Latin word meaning by the hundred. The symbol "%" is used for the word percent. A numerator in a fraction having 100 as a denominator expresses a percent. Examples: 1. Convert fraction or decimals to percent 0.005 = 5/1000= 5/1000x100% = 0.5% 2. Convert percent to fraction or decimals a. 0.7% = 0.7/100 =7/1000= 0.007 b. 150% = 150/100 = 1.50 More examples a. 1% of 7823 =7823x(1/100)= 78.23 b. 68% of 300 =300x(68/100)= 204 c. 15 is what percent of 750? d. If 30 is 75% of some number Y, to find Y solve 30 = (75/100) Y; Y = 40 Surveying for Engineers – Dr. Mwafag Ghanma (15/750)x100% = 2% 14 Ratio and Proportion • A ratio is a comparison of two values or quantities. Formats: • The ratio of 2 to 5, • 2:5 • 2 ÷ 5, or • 2 / 5, are all expressions of the same ratio. • In surveying applications ratios are expressed in the form of: • • • • 1 to x 1:x 1 ÷ x, or 1/x • A proportion is a statement of equality between two ratios. The same proportion can be expressed as 2:5 = 4:10, 2 ÷ 5 = 4 ÷ 10, or 2/5 = 4/10. Surveying for Engineers – Dr. Mwafag Ghanma 15 Types of Angles Acute Angle Complementary Angles Alternate Interior Angles Surveying for Engineers – Dr. Mwafag Ghanma Obtuse Angle Straight Angle Supplementary Angles Alternate Exterior Angles 16 Types of Angles What is this angle called? ? Surveying for Engineers – Dr. Mwafag Ghanma 17 Types of Angles Name the pointed angles. Surveying for Engineers – Dr. Mwafag Ghanma 18 Polygons • A closed figure bounded by straight lines lying in the same plane is known as a polygon. • The sum of the interior angles of a closed polygon is equal to: (n - 2) (180) n is the number of sides. Examples • sum of the interior angles of a triangle is 180°, • of a rectangle 360°, • of a five-sided figure 540°, and so on. Surveying for Engineers – Dr. Mwafag Ghanma 19 Polygons • The sum of the interior angles = (n - 2) (180) with n is the number of sides (nodes). • Derive a similar formula for the sum of exterior angles Surveying for Engineers – Dr. Mwafag Ghanma 20 Polygons + (n-2)*180 + = X = n*2*180 X = n*2*180 - (n-2)*180 X = (2n – n + 2) * 180 X = (n + 2) * 180 Surveying for Engineers – Dr. Mwafag Ghanma 21 Polygons Common polygons Polygon Number of Sum of interior sides angles (n - 2) x 180° If regular, size of EACH interior angle, ° ‘ “ Sum of exterior If regular, size of each angles (n + 2) x 180° exterior angle, ° ‘ “ Triangle 3 180° 60° 0' 0" 900° 300° 0' 0" Square 4 360° 90° 0' 0" 1080° 270° 0' 0" Pentagon 5 540° 108° 0' 0" 1260° 252° 0' 0" Hexagon 6 720° 120° 0' 0" 1440° 240° 0' 0" Heptagon 7 900° 128° 34' 17.14" 1620° 231° 25' 42.86" Octagon 8 1080° 135° 0' 0" 1800° 225° 0' 0" Nonagon 9 1260° 140° 0' 0" 1980° 220° 0' 0" Decagon 10 1440° 144° 0' 0" 2160° 216° 0' 0" Surveying for Engineers – Dr. Mwafag Ghanma 22 Triangles (smallest polygon) Right Triangle Isosceles triangle Equilateral triangle Oblique triangle (Scalene) Similar triangles (same shape, but different sizes) Surveying for Engineers – Dr. Mwafag Ghanma 23 Triangles Exercise: Find the measure of angle x T/F: If a triangle is equilateral, then it is isosceles. T/F: If a triangle is isosceles, then it is also equilateral. Surveying for Engineers – Dr. Mwafag Ghanma 24 Triangles Exercise: Which of the following triangles are always similar? Right Triangle Isosceles triangle Equilateral triangle Exercise: The sides of a triangle are 5, 6 and 10. Find the length of the longest side of a similar triangle whose shortest side is 15. T/F: Similar triangles are exactly the same shape and size? Surveying for Engineers – Dr. Mwafag Ghanma 25 Solution to Right Triangles The Pythagorean Theorem In a right triangle, the square of the hypotenuse is equal to the sum of the squares of the other two sides. Surveying for Engineers – Dr. Mwafag Ghanma 26 Solution of Oblique Triangles • Any triangle has six parts: 3 angles, and 3 sides • An oblique triangle can be solved if three of its parts, at least one of which is a side, are known. • Oblique triangles can be solved by the use of formulas of law of sines or law of cosines Surveying for Engineers – Dr. Mwafag Ghanma 27 Solution of Oblique Triangles General Cases: • SSS - Side, Side, Side: 1. Law of Cosines → Find any angle 2. Law of cosines or law of sines → Find another angle 3. Law of cosines or law of sines or summation of angles → Find the last angle • SAS - Side, Angle, Side 1. Law of Cosines → Find the third side 2. Law of cosines or law of sines → Find one unknown angle 3. Law of cosines or law of sines or summation of angles → Find the last angle Surveying for Engineers – Dr. Mwafag Ghanma 28 Solution of Oblique Triangles General Cases: • ASA - Angle, Side, Angle: 1. Summation of angles → Find the third angle 2. Law of sines → Find another side 3. Law of cosines or law of sines → Find the last side • SAA = AAS - Angle, Angle, Side 1. Summation of angles → Find the third angle 2. Law of sines → Find the 2nd side 3. Law of cosines or law of sines → Find the last side Surveying for Engineers – Dr. Mwafag Ghanma 29 Solution of Oblique Triangles • ASS or SSA - Side, Side, Angle: Surveying for Engineers – Dr. Mwafag Ghanma 30 Solution of Oblique Triangles Example Solve for the unknowns: A, a, b. This is a SAA or AAS case Start with summation of angles A = 180-(83 + 61) = 36 Continue with the law of sines Surveying for Engineers – Dr. Mwafag Ghanma 31 Solution of Oblique Triangles Example Solve for the unknown side and two angles. This is a SAS case Start with the law of cosines then continue with the law of sines MN = 60 2 + 50 2 − 2 60 50 cos120 = 3600 + 2500 − 6000 0.50 = 95m 50 sin 120 sin M = = 0.45580 95 M = 27 60 sin 120 sin N = = 0.54696 95 N = 33 Surveying for Engineers – Dr. Mwafag Ghanma 32 Solution of Oblique Triangles Example Solve triangle ABC with sides a = 3.0, b = 5.0, and c = 6.0 This is an SSS case Start with the Law of Cosines and continue with either with law of cosines or law of sines. 5 .0 2 + 6 . 0 2 − 3 .0 2 cos A = 2 5 . 0 6. 0 25 + 36 − 9 = 60 A = 30 3.0 2 + 6.0 2 − 5.0 2 cos B = 2 3.0 6.0 9 + 36 − 25 = 36 B = 56 3.0 2 + 5.0 2 − 6.0 2 cosC = 2 3.0 5.0 9 + 25 − 36 = = −0.067 30 C = 94 The negative value of cos C indicates that the angle is greater than 90° Surveying for Engineers – Dr. Mwafag Ghanma 33 Solution of Oblique Triangles Example Surveying for Engineers – Dr. Mwafag Ghanma 34 Solution of Oblique Triangles Example Surveying for Engineers – Dr. Mwafag Ghanma 35 Solution of Oblique Triangles Example Surveying for Engineers – Dr. Mwafag Ghanma 36 Solution of Oblique Triangles Example Surveying for Engineers – Dr. Mwafag Ghanma 37 Solution of Oblique Triangles Example Surveying for Engineers – Dr. Mwafag Ghanma 38 Solution of Oblique Triangles Example Surveying for Engineers – Dr. Mwafag Ghanma 39 Rectangles and Squares A rectangle is a four-sided polygon whose angles are right angles. A square is a rectangle whose sides are equal. Surveying for Engineers – Dr. Mwafag Ghanma 40 Trapezoids A trapezoid is a four-sided polygon that has two parallel sides and two nonparallel sides. Surveying for Engineers – Dr. Mwafag Ghanma 41 Parallelograms and Rhombi A parallelogram is a four-sided polygon with pairs of parallel sides. A rhombus (plural – rhombi) is its special case with all sides equal (equilateral). Parallelogram Surveying for Engineers – Dr. Mwafag Ghanma Rhombus Rhombus 42 Circles A circle is a closed plane curve, all points on which are equidistant from a point within called the center. Surveying for Engineers – Dr. Mwafag Ghanma 43 Length of an Arc The length of an arc (L) of a circle is proportional to its central angle (). A central angle of 90 (one-fourth of 360°) subtends an arc that is one-fourth the circumference in length. L=r is in radians here. Example Find the length of an arc of a 100 m circle that has a central angle of 36°. Arc Length = Surveying for Engineers – Dr. Mwafag Ghanma 36 100 100 = = 31.42m 360 10 44 Perimeter It is a path that surrounds a two-dimensional shape. The sum of the lengths of the sides of a polygon is called the perimeter of the polygon. Perimeter = 2L + 2W Perimeter = 4S Perimeter = a + b + c Example Triangle Hypotenuse = 2.25 2 + 6.15 2 = 42.885 = 6.55cm Perimeter = 2.25 + 6.15 + 6.55 = 14.95 cm Surveying for Engineers – Dr. Mwafag Ghanma 45 Circumference It is the perimeter of a circle or an ellipse. The sum of the lengths of the sides of a polygon is called the perimeter of the polygon. Circumference = 2r Approximation 1 Approximation 2 Surveying for Engineers – Dr. Mwafag Ghanma 46 Straight Line Equation Equation of the line is 𝒚 = 𝒃 + 𝒎𝒙 b is the y-intercept m is the slope of the line 𝒎= ∆ 𝒗𝒆𝒓𝒕𝒊𝒄𝒂𝒍 ∆ 𝒉𝒐𝒓𝒊𝒛𝒐𝒏𝒕𝒂𝒍 = ∆𝒚 ∆𝒙 Example Find the equation of a straight line that goes through two coordinates (-1, 5) and (5, -1). Solution −𝟏−𝟓 m = 𝟓−−𝟏 = −𝟏 b = 𝒚𝟏 − 𝒎𝒙𝟏 = 𝑦𝟐 − 𝒎𝑥𝟐 = −𝟏 − (−𝟏) × 𝟓 = 𝟒 The equation is 𝒚 = 𝟒 − 𝒙 Surveying for Engineers – Dr. Mwafag Ghanma 47