Note for Surveying-1 - s-1 By JNTU Heroes

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LECTURE NOTE ENGINEERNG SURVEYING Under revision

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ENGG. SURVEYING Module –I (10 Hrs) 1. Concept of Surveying- Definition of surveying, Classification, Principle, Accuracy 2. Linear Measurement- Different methods of direct measurement instrument for chaining, Ranging, Chaining on uneven slopping ground, Errors in Chaining, Corrections. 3. Chain Surveying – Chain triangulation, Survey stn., lines, locating ground features, field work, instruments for setting out basic problems in chaining, obstacles in chaining Module –II (10 Hrs) 4. Compass Surveying – Principles use of Prismatic Compass, Measurement of bearings, Conversion of bearings, Local attraction, Correction of compass traverse. 5. Plane Table Survey- Principles, Advantages and disadvantages, Equipment, Accessories and their uses. Methods of plane table survey. Two point and three point problems. Module –III (10 Hrs) 6. Levelling- Types of levelling and their uses, Permanent adjustment, Curvature and refraction effects. 7. Contouring-Characteristics and uses of contours. Methods of contouring. Module –IV (10 Hrs) 8. Theodolite Survey – Application in Height and distance measurements. Permanent adjustment of transit theodolite, methods of repetitions and reiterations. 9. Curve Setting – Simple circular curve setting by chain, tape & theodolite 10. Minor Survey Instruments – Box-sextant, Planimeter, Pantagraph, their working principles and uses. Reference Books: 1. Surveying & Levelling – Kanetkar & Kulkarni, Vol.-I, Pune Vidyarthi Griha Prakashan. 2. Surveying – Punmia, Vol. – I, Laxmi Publication. 3. Surveying – S.K. Duggal, Tata McGraw Hill Under revision

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LECTURE 1 Introduction: • Surveying is defined as “taking a general view of, by observation and measurement determining the boundaries, size, position, quantity, condition, value etc. of land, estates, building, farms mines etc. and finally presenting the survey data in a suitable form”. This covers the work of the valuation surveyor, the quantity surveyor, the building surveyor, the mining surveyor and so forth, as well as the land surveyor. • Another school of thought define surveying “as the act of making measurement of the relative position of natural and manmade features on earth’s surface and the presentation of this information either graphically or numerically. The process of surveying is therefore in three stages namely: (i) Taking a general view This part of the definition is important as it indicates the need to obtain an overall picture of what is required before any type of survey work is undertaken. In land surveying, this is achieved during the reconnaissance study. (ii) Observation and Measurement (iii) This part of the definition denotes the next stage of any survey, which in land surveying constitutes the measurement to determine the relative position and sizes of natural and artificial features on the land. Presentation of Data: The data collected in any survey must be presented in a form which allows the information to be clearly interpreted and understood by others. This presentation may take the form of written report, bills of quantities, datasheets, drawings and in land surveying maps and plan showing the features on the land. Types of Surveying On the basis of whether the curvature of the earth is taken into account or not,surveying can be divided into two main categories: Plane surveying: is the type of surveying where the mean surface of the earth is considered as a plane. All angles are considered to be plane angles. For small areas less than 250 km2 plane surveying can safely be used. For most engineering projects such as canal, railway, highway, building, pipeline, etc constructions, this type of surveying is used. It is worth noting that the difference between an arc distance of 18.5 km and the subtended chord lying in the earth’s surface is 7mm. Also the sum of the angles of a plane triangle and the sum of the angles in a spherical triangle differ by 1 second for a triangle on the earth’s surface having an area of 196 km2. Under revision

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Geodetic surveying: is that branch of surveying, which takes into account the true shape of the earth (spheroid). Classification of surveying Introduction For easy understanding of surveying and the various components of the subject, we need a deep understanding of the various ways of classifying it. Objective To enable the students have understanding of the various ways of classifying surveying Classification Of Surveying Surveying is classified based on various criteria including the instruments used, purpose, the area surveyed and the method used. Classification on the Basis of Instruments Used. Based on the instrument used; surveys can be classified into; i) Chain tape surveys ii) Compass surveys iii) Plane table surveys iv) Theodelite surveys Classification based on the surface and the area surveyed i) Land survey Land surveys are done for objects on the surface of the earth. It can be subdivided into: (a) Topographic survey: This is for depicting the (hills, valleys, mountains, rivers, etc) and manmade features (roads, houses, settlements…) on the surface of the earth. (b) Cadastral survey is used to determining property boundaries including those of fields, houses, plots of land, etc. (c) Engineering survey is used to acquire the required data for the planning, design and Execution of engineering projects like roads, bridges, canals, dams, railways, buildings, etc. Under revision