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CEFS0214 – Fundamentals of Surveying Learning Module 01 Basic Surveying Concepts and Measurements Learning Packet 02 Introduction to Surveying 15 ...

CEFS0214 – Fundamentals of Surveying Learning Module 01 Basic Surveying Concepts and Measurements Learning Packet 02 Introduction to Surveying 15  CEFS0214 – Fundamentals of Surveying Learning Packet 02 Introduction to Surveying Introduction In this learning packet, the general concept of Surveying and its relevance to Civil Engineering will be discussed. Necessary information on Surveying field practice and common surveying equipment will also be discussed. Objectives At the end of this learning packet, the students are expected to understand and to be able to discuss the basic concepts of Surveying. Duration Topic 01: Introduction to Surveying = 2 hours (1 hour for lecture, 1 hour for activity and assessment) Delivery Mode Online (synchronous or asynchronous) Readings Part I: Lessons 1-4, Elementary Surveying, 3rd Edition. Juny Pilapil La Putt. Pre-Assessment Questions: 1. Differentiate the two general classifications of Surveying? 2. What are the basic units used in surveying for length, area, volume, and angles in SI system of units? 3. Why the data should always be entered directly into the field notebook at the time measurements are made? 4. What is a systematic error? Give two (2) surveying examples of a systematic error. 5. Explain the difference between accuracy and precision. Basic Surveying Concepts and Measurement Introduction to Surveying 16  CEFS0214 – Fundamentals of Surveying Surveying is traditionally defined as a branch of applied mathematics that teaches the art of determining the Key Points: relative position of points above, on, or beneath the Earth’s surface, or establishing such points. However, the manner Surveying Operations Surveying Field Practice and scope of practice in surveying have changed Errors dramatically in recent years. A new term is now commonly Accuracy being applied to encompass the areas of practice. The Precision term geomatics has recently been used interchangeably Definition of Terms: with surveying. It covers a broader and more complex process of data gathering, and it involves using modern Geomatics. An applied technologies. science that involves an integrated approach to the measurement, analysis, The International Federation of Surveyors adopted the management, and display following definition of the functions of the surveyor: of geographic and other spatial data. Measurement. Process of “A surveyor is a professional person with the academic obtaining size, extent, and qualifications and technical expertise to conduct one, or more, dimensions of a certain quantity based on a given of the following activities; standard. to determine, measure and represent land, three- dimensional objects, point-fields and trajectories; to assemble and interpret land and geographically related information, to use that information for the planning and efficient administration of the land, the sea and any structures thereon; and, to conduct research into the above practices and to develop them. Detailed Functions The surveyor’s professional tasks may involve one or more of the following activities which may occur either on, above or below the surface of the land or the sea and may be carried out in association with other professionals. 1. The determination of the size and shape of the earth and the measurement of all data needed to define the size, position, shape and contour of any part of the earth and monitoring any change therein. 2. The positioning of objects in space and time as well as the positioning and monitoring of physical features, structures and engineering works on, above or below the surface of the earth. 3. The development, testing and calibration of sensors, instruments and systems for the above-mentioned purposes and for other surveying purposes. Basic Surveying Concepts and Measurement Introduction to Surveying 17  CEFS0214 – Fundamentals of Surveying 4. The acquisition and use of spatial information from close range, aerial and satellite imagery and the automation of these processes. 5. The determination of the position of the boundaries of public or private land, including national and international boundaries, and the registration of those lands with the appropriate authorities. 6. The design, establishment and administration of geographic information systems (GIS) and the collection, storage, analysis, management, display and dissemination of data. 7. The analysis, interpretation and integration of spatial objects and phenomena in GIS, including the visualization and communication of such data in maps, models and mobile digital devices. 8. The study of the natural and social environment, the measurement of land and marine resources and the use of such data in the planning of development in urban, rural and regional areas. 9. The planning, development and redevelopment of property, whether urban or rural and whether land or buildings. 10. The assessment of value and the management of property, whether urban or rural and whether land or buildings. 11. The planning, measurement and management of construction works, including the estimation of costs. In the application of the foregoing activities surveyors take into account the relevant legal, economic, environmental and social aspects affecting each project.“ Two General Classification of Surveying 1. Plane Surveying This type of surveying deals with areas of limited extent, and the spheroidal shape of the earth is neglected. The earth’s surface is considered as a plane. 2. Geodetic Surveying This type of survey requires high precision, and it covers relatively large areas. The spheroidal shape of the earth and the effects of earth’s curvature is considered. Basic Surveying Concepts and Measurement Introduction to Surveying 18  CEFS0214 – Fundamentals of Surveying Types of Surveys (Operations in Surveying) Cadastral Surveys: Surveys in urban and rural locations to establish and determine area, property lines, and boundaries. It is a survey of public lands and it is executed to fix boundaries of municipalities and provincial jurisdictions. Construction Surveys: Surveys undertaken in a construction project to provide essential data for planning, construction, and post-construction operation. The data obtained in this type of survey includes grades, reference lines, dimensions, ground configurations, and location and elevation of structures. Hydrographic Surveys: Surveys performed in different bodies of water to map shorelines, chart the shape of area underlying water surfaces, and measure the flow of streams. Industrial Surveys (Optical tooling): The use of surveying techniques in manufacturing plants and other industries to make extremely accurate measurements and dimensional layout. It is used in ship building, construction and assembly of aircraft, and heavy machinery installation. Mine Surveys: Surveys performed in a mining site to guide the tunneling and positioning of all underground excavations and surface mine structures. It is also done to fix surface boundaries of mining claims, and calculate excavated volumes. Photogrammetric Surveys: This type of survey uses high-quality photographs to obtain data and other measurements. Photos are taken from airplanes or elevated ground stations. Route Surveys: Surveys carried out to plan, design, and construct highways, railroads, pipelines, drainage, and other linear projects. Topographic Surveys: Surveys that determine the locations of natural and artificial features used in making a map. It is also executed to determine the shape of the ground. Surveying Measurements 1. Direct Measurements Direct measurements are done by using a measuring instrument directly to the quantity or dimension to be measured. Examples of this measurement are using a tape to measure a line, fitting a protractor to measure an angle, and using transit or theodolite to measure vertical and horizontal angles. Basic Surveying Concepts and Measurement Introduction to Surveying 19  CEFS0214 – Fundamentals of Surveying 2. Indirect Measurements Indirect measurements are employed when it is not possible to use a measuring instrument directly to the quantity or dimension to be measured. The value is determined by its relationship to some other observed or known values. For example, the length of a line is needed, but there are obstructions somewhere in the middle of it, so the surveyor will find other ways to measure it. It can be determined by using the properties of a triangle and other calculations using trigonometric functions. Units of Measurement The magnitude of measurements must be expressed in terms of standard units. In the Philippines, the most commonly used system of units is the International System of Units (SI Units). Linear, Area, and Volume Measurements SI base unit of length: meter (m) SI derived unit for area: square meter (m2) SI derived unit for volume: cubic meter (m3) Angular Measurements The SI unit for plane angle is radian. However, the widely used units in surveying for angular measurement is the sexagesimal units, which are non-SI units accepted for use with the SI units. The sexagesimal units are the degree, minute, and second. A degree is equal to 1/360 of a circle. One degree (1°) is equal to sixty minutes (60’), and one minute (1’) is equal to sixty seconds (60”). 𝜋 1° = 𝑟𝑎𝑑 180 Student Field Practice Surveying Field Notes The field notes are the reliable and permanent records of work done in the field. It is vital to keep records organized because the quality of the fieldwork is reflected directly in the manner of keeping field records. Resources will be wasted if the notes Basic Surveying Concepts and Measurement Introduction to Surveying 20  CEFS0214 – Fundamentals of Surveying are incorrect or incomplete. A survey may be useless no matter how carefully measurements are made if some of the measurements are not recorded or if the recorded data's meaning is misinterpreted or misunderstood. The following points are considered in appraising a set of field notes*: Accuracy. This is the most important quality in all surveying operations. Integrity. A single omitted measurement or detail can nullify use of the notes for computing or plotting. If the project was far from the office, it is time-consuming and expensive to return for a missing measurement. Notes should be checked carefully for completeness before leaving the survey site and never “fudged” to improve closures. Legibility. Notes can be used only if they are legible. A professional-looking set of notes is likely to be professional in quality. Arrangement. Note forms appropriate to a particular survey contribute to accuracy, integrity, and legibility. Clarity. Advance planning and proper field procedures are necessary to ensure clarity of sketches and tabulations, and to minimize the possibility of mistakes and omissions. Avoid crowding notes; paper is relatively cheap. Costly mistakes in computing and drafting are the end results of ambiguous notes. * Ghilani, C. & Wolf, P. (2012). Elementary Surveying: An Introduction to Geomatics, 13th Ed. The Field Notebook Types of Notes 1. Sketches 2. Tabulations 3. Explanatory Notes 4. Computations 5. Combination of the above Information Found in Field Notebooks 1. Title of the Fieldwork or Name of Project 2. Time of day and Date 3. Weather Conditions 4. Name of group members and their designations 5. List of equipment Basic Surveying Concepts and Measurement Introduction to Surveying 21  CEFS0214 – Fundamentals of Surveying The Field Survey Party Chief of Party Asst. Chief of Party Instrument man Technician Computer Recorder Head Tapeman Rear Tapeman Flag man Rod man Pacer Axeman / Lineman Aid man Utility men Errors Measurements are never exact and will always contain errors no matter how carefully it is done. An error is the difference between the true value and the measured value of a quantity. A surveyor should know and understand the different kinds of errors, their sources, and their manner of propagation to select the instruments and procedures necessary to minimize the errors. Types of Errors* Systematic Errors This type of error is one which will always have the same sign and magnitude as long as field conditions remain constant and unchanged. It will repeat itself in other measurements, still maintaining the same sign, and thus will accumulate. It is for this reason that this type of error is also called a cumulative error. Accidental Errors These errors are purely accidental in character. There is no absolute way of determining or eliminating them and they are caused by factors beyond the control of the surveyor. They remain after mistakes and systematic errors have been eliminated. * La Putt. Elementary Surveying, 3rd Ed. Basic Surveying Concepts and Measurement Introduction to Surveying 22  CEFS0214 – Fundamentals of Surveying Sources of Errors Instrumental Errors It results from the imperfections of instruments used, either from the instrument's faulty construction or the improper adjustment of different parts before its use. Natural Errors These are caused by variations in natural phenomena and are beyond the control of man. Necessary precautions must be taken in order to minimize the resulting error and keep within the acceptable limit. Personal Errors Errors arise from the limitation of the human observer's senses, which are likely to be erroneous or inaccurate. These errors may be reduced or eliminated by developing and improving surveying operations skills through constant practice and experience. Accuracy and Precision In surveying, accuracy and precision are frequently used terms, and sometimes their meanings are misunderstood. The terms must not be confused and used interchangeably. Accuracy indicates the absolute nearness of measured quantities to their true or absolute value. Precision refers to the degree of refinement of measurements or the closeness of the measurements to each other. An example to distinguish the difference between accuracy and precision is illustrated in Fig. 1. It shows different targets with sets of riffle shots. In Fig.1-a, the riffle shots were clustered close to each other which indicates a precise operation. However, they were not accurate because the riffle shots were far from the bull’s eye. In Fig 1-b, the riffle shots were placed relatively close to the bull’s eye which indicates accuracy but with poor precision because the shots were scattered near the bull’s eye. The results Basic Surveying Concepts and Measurement Introduction to Surveying 23  CEFS0214 – Fundamentals of Surveying in Fig 1-c represents both accuracy and precision because the riffle shots were placed within the bull’s eye and closely clustered. Fig. 1-d portrays poor precision and accuracy since the riffle shots were far from the bull’s eye and scattered all over the target frame. (a) (b) (c) (d) Good Precision But Good Accuracy But Good Accuracy And Poor Precision And Poor Accuracy Poor Precision Good Precision Poor Accuracy Fig. 1. Accuracy and Precision It is essential to take measurements with accuracy and precision. The degree of precision and accuracy is dependent on instrument sensitivity and the surveyor’s skill. However, it should be the responsibility of the surveyor to obtain a precise and accurate measurement. The surveyor must increase the time and effort to increase the degree of precision in measurement. Common Surveying Instruments and Tools Measuring Tape It is the most common surveying equipment used to measure distances. There are several types of measuring tapes, which vary in length, material, and weight. Steel Tape, Invar Tape, and Fiberglass tape are some of the types of measuring tapes. https://www.engineersupply.com/ Measuring Wheel An equipment to measure long distances quickly but with lower accuracy. It is rolled from the start to end point and the revolutions are counted by a mechanical device attached to the wheel that gives measurement directly. https://www.engineersupply.com/ Basic Surveying Concepts and Measurement Introduction to Surveying 24  CEFS0214 – Fundamentals of Surveying https://www.engineersupply.com/ Range Pole Range poles are used to mark points which must be seen from a distance to set out straight lines in the field. Plumb bob It is a pointed weight suspended from a string to find a vertical reference line. It is used to check if the object is vertical. https://www.engineersupply.com/ Engineer’s Transit A traditional instrument that measures and lay off horizontal and vertical angles. It is composed of a telescope with two large protractors. It is usually referred to as the “universal surveying instrument” because of its wide variety https://www2.humboldt.edu/scimus/AvH_HSU_C of uses. entenial%20Exhibit/Lietz_Transit/Transit_357.jpg Automatic Level Automatic level is the most commonly employed type of level. It consists of a telescope-like device that is mounted on a tripod stand. It employs automatic compensator to orient the line of sight in a horizontal plane. It is used with a leveling rod to https://www.engineersupply.com/ measure elevation and height differences. Tripod Tripods acts as a support to most surveying instruments. It has three legs that can be adjusted as required. https://www.engineersupply.com/ Basic Surveying Concepts and Measurement Introduction to Surveying 25  CEFS0214 – Fundamentals of Surveying Leveling Rods A leveling rod is a graduated rod used for measuring the vertical distance through a leveling instrument. The rod's graduations start from zero at the bottom and extending upward to a length that ranges from 3 to 4 meters. https://civiltoday.com/surveying/186-stadia-rod Theodolite Theodolites are modern version of the transit. It measures horizontal and vertical angles more precisely than the transit. It consists of a moveable telescope attached over a perpendicular axis and it is mounted on a tripod. Some models use an electronic rotary encoder to read the horizontal and vertical https://www.engineersupply.com/ circles. Total Station A total station is a modern surveying instrument fitted with an electronic distance meter (EDM). A microprocessor unit, an electronic data collector, and a storage system are embedded in the instrument to collect and process the data. The processed data can be downloaded to process it further using computer software like Computer-Aided Design (CAD), Building Information https://www.engineersupply.com/ Modelling (BIM), and Geographic Information System (GIS). Please watch the videos to learn more about the common surveying equipment. https://youtu.be/KoHJmAxcZvE https://youtu.be/Y1Lgmrw4OvE Basic Surveying Concepts and Measurement Introduction to Surveying 26  CEFS0214 – Fundamentals of Surveying REFERENCES Juny Pilapil La Putt. Elementary Surveying, 3rd Edition. Charles D. Ghilani, Paul R. Wolf (2012). Elementary Surveying: An Introduction to Geomatics, 13th Edition. Michael Minchin (2003). Introduction to Surveying, 2nd Edition. International Federation of Surveyors, https://www.fig.net/about/general/definition/index.asp Barry N. Taylor, Ambler Thompson (2008). The International System of Units (SI). National Institute of Standards and Technology Special Publication 330, 2008 Edition Elementary Surveying Equipment, http://www.fao.org/3/r7021e/r7021e02.htm Basic Surveying Concepts and Measurement Introduction to Surveying 27  CEFS0214 – Fundamentals of Surveying Activity Sheet Instruction: Prepare a summary of a case study or an article from a professional journal related to the subject matter of this course packet. The required format and template are uploaded in Google Classroom. Basic Surveying Concepts and Measurement Introduction to Surveying 28  CEFS0214 – Fundamentals of Surveying Assignment Instruction: List at least five (5) modern surveying instruments. Include descriptions and images. Homework format and template are uploaded in the Google Classroom. Basic Surveying Concepts and Measurement Introduction to Surveying 29  CEFS0214 – Fundamentals of Surveying Learner’s Feedback Form Name of Student: __________________________________________________________ Program : __________________________________________________________ Year Level : ______________ Section : __________________ Faculty : __________________________________________________________ Schedule : __________________________________________________________ Course Packet : Code : _________ Title : __________________________________ How do you feel about the topic or concept presented? o I completely get it. o I’m struggling. o I’ve almost got it. o I’m lost. In what particular portion of this course packet, you feel that you are struggling or lost? _____________________________________________________________________________ _____________________________________________________________________________ __________________________________________________________________________ Did you raise your concern to you instructor? o Yes o No If Yes, what did he/she do to help you? _____________________________________________________________________________ _____________________________________________________________________________ __________________________________________________________________________ If No, state your reason? _____________________________________________________________________________ _____________________________________________________________________________ __________________________________________________________________________ To further improve this course packet, what part do you think should be enhanced? _____________________________________________________________________________ _____________________________________________________________________________ __________________________________________________________________________ How do you want it to be enhanced? _____________________________________________________________________________ _____________________________________________________________________________ __________________________________________________________________________ Basic Surveying Concepts and Measurement Introduction to Surveying 30