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Civil Engineering · 400 Level
This is the complete lecture note for CEE 406 Engineering Surveying and Photogrammetry II, prepared for Civil Engineering students at 400 Level. You can read it online below, open it in the full viewer, or download the PDF for offline study. It pairs with the course's video lectures, so you can read and watch together.
LA-NET | ONLINE LEARNING VIDEO PLATFORM FOR POST-SECONDARY & HIGHER INSTITUTION STUDENTS
LA-NET | ONLINE LEARNING VIDEO PLATFORM FOR POST-SECONDARY & HIGHER INSTITUTION STUDENTS COURSE CODE: CEE 406 COUSE TITLE: Engineering Surveying and Photogrammetry II COURSE CREDIT LOAD: 3 UNITS SERIES 1 Contours and Contouring in Surveying SERIES 2 Computation of Areas and Volumes SERIES 3 Setting Out Engineering Works SERIES 4 Elementary Topographical Surveying SERIES 5 Fundamentals of Photogrammetry Series 1: Contours and Contouring in Surveying Series outline 1.1 Fundamentals of Contours • 1.1.1 Definition and characteristics of contours • 1.1.2 Principles of contour representation • 1.1.3 Applications of contour maps in engineering 1.2 Methods of Contouring • 1.2.1 Direct methods of contouring • 1.2.2 Indirect methods of contouring • 1.2.3 Comparative advantages and limitations 1.3 Contour Interpolation • 1.3.1 Definition and purpose of interpolation • 1.3.2 Arithmetic and graphical methods • 1.3.3 Practical examples and exercises 1.4 Uses of Contour Plans and Maps • 1.4.1 Engineering design applications • 1.4.2 Hydrological and environmental uses • 1.4.3 Planning and construction relevance
LA-NET | ONLINE LEARNING VIDEO PLATFORM FOR POST-SECONDARY & HIGHER INSTITUTION STUDENTS 1.5 Errors and Accuracy in Contouring • 1.5.1 Sources of errors in contouring • 1.5.2 Techniques for minimising errors • 1.5.3 Quality assurance in contour surveys Introduction Surveying often requires a clear understanding of the land surface, and one of the most effective ways to represent this is through contours, which are lines connecting points of equal elevation. Contour maps are widely used in engineering, construction, and environmental studies because they provide a visual representation of terrain that supports planning and design. In this Series, you will be introduced to the principles and practices of contouring, which form a foundation for many advanced surveying and photogrammetry applications. The aim of this Series is to equip you with the knowledge and skills to define, construct, and apply contour maps effectively, while also recognising potential errors and ensuring accuracy in contour surveys. We shall commence this Series by examining the fundamentals of contours, including their definition, characteristics, and applications. Next, we will explore the different methods of contouring, both direct and indirect, and consider their advantages and limitations. Following that, we will study contour interpolation, focusing on arithmetic and graphical techniques. Subsequently, we will discuss the uses of contour plans and maps in engineering, hydrology, and construction. Finally, we will wrap up by addressing errors and accuracy in contouring, highlighting techniques for minimising mistakes and ensuring reliable survey outputs. Series Learning Outcomes Upon completing this Series, you should be able to: • SLO 1.1 define contours and explain their fundamental characteristics, • SLO 1.2 analyse the principles of contour representation and their applications in engineering surveying, • SLO 1.3 demonstrate the use of direct and indirect methods of contouring, • SLO 1.4 apply arithmetic and graphical techniques of contour interpolation to practical survey data, • SLO 1.5 evaluate the uses of contour plans and maps in engineering design, hydrological studies, and construction planning, and • SLO 1.6 identify sources of errors in contouring and propose techniques for ensuring accuracy in contour surveys. 1.1 Fundamentals Of Contours
LA-NET | ONLINE LEARNING VIDEO PLATFORM FOR POST-SECONDARY & HIGHER INSTITUTION STUDENTS 1.1.1 definition and characteristics of contours A contour is a line drawn on a map that connects points of equal elevation above a reference level, usually mean sea level. Contours provide a way of representing three-dimensional terrain on a two-dimensional surface. The spacing and shape of contour lines reveal important information about the slope, relief, and form of the land. Basic properties of contour lines • Contours never cross each other, since a point cannot have two different elevations. • Closely spaced contours indicate steep slopes, while widely spaced contours suggest gentle slopes. • Closed contours represent hills or depressions, depending on whether the values increase or decrease towards the centre. Fill in the blank: A line connecting points of equal elevation is called a ________. Description: A simple diagram showing contour lines around a hill, with labels for steep and gentle slopes. Caption: Figure 1.1 Contour lines representing a hill :
LA-NET | ONLINE LEARNING VIDEO PLATFORM FOR POST-SECONDARY & HIGHER INSTITUTION STUDENTS 1.1.2 principles of contour representation Contour representation follows certain rules to ensure clarity and accuracy. Contours are usually drawn at regular vertical intervals, known as the contour interval, which is the difference in elevation between successive contour lines. The choice of interval depends on the scale of the map and the nature of the terrain. Rules for drawing contours • Contours are labelled with their elevation values at suitable points for easy identification. • Smooth curves are preferred, avoiding sharp angles unless dictated by terrain features. • Index contours, which are thicker lines drawn at regular intervals (e.g., every fifth contour), help in quickly reading elevations. Fill in the blank: The vertical difference in elevation between successive contour lines is called the ________. Table 1.1 Typical contour intervals for different map scales Description: A table showing examples of contour intervals used in large-scale and small-scale maps. “
LA-NET | ONLINE LEARNING VIDEO PLATFORM FOR POST-SECONDARY & HIGHER INSTITUTION STUDENTS 1.1.3 applications of contour maps in engineering Contour maps are widely used in engineering because they provide essential information for design and construction. For example, they are used to determine the best alignment for roads, railways, and pipelines, to plan drainage systems, and to estimate earthwork quantities. Examples of engineering uses • Designing road gradients and curves to suit terrain. • Locating reservoirs and planning irrigation channels. • Preparing site plans for buildings and other structures. Fill in the blank: Contour maps are essential in engineering because they help in planning ________ and estimating earthwork quantities. Box 1.1 Selected engineering applications of contour maps Description: A boxed list highlighting practical uses such as road design, drainage planning, and site preparation. Pilot questions 1.1
LA-NET | ONLINE LEARNING VIDEO PLATFORM FOR POST-SECONDARY & HIGHER INSTITUTION STUDENTS 1. Which property of contour lines indicates a steep slope? 2. What is the term used for the vertical difference between successive contour lines? 3. Why can contour lines never cross each other? 4. Give one example of how contour maps are used in engineering design. 5. What is the purpose of index contours on a map? 1.2 Methods Of Contouring 1.2.1 direct methods of contouring In the direct method of contouring, surveyors locate points of equal elevation directly on the ground and mark them before plotting on the map. This approach is straightforward and provides high accuracy, but it is time-consuming and labour-intensive. It is most suitable for small areas where precision is critical, such as construction sites. Fill in the blank: The method of contouring where points of equal elevation are located directly on the ground is called the ________ method. Plate 1.1 Direct method of contouring in practice
LA-NET | ONLINE LEARNING VIDEO PLATFORM FOR POST-SECONDARY & HIGHER INSTITUTION STUDENTS “ 1.2.2 indirect methods of contouring The indirect method of contouring involves first conducting a detailed survey of the area, then interpolating contour lines from the measured data. This method is faster and more practical for large areas, though it may be less precise than the direct method. Common techniques include grid surveys, radial line surveys, and tacheometric surveys. Fill in the blank: The method of contouring where contour lines are drawn from measured survey data is called the ________ method. Figure 1.2 Indirect method of contouring using grid survey
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