This article throws light upon the six major problems in ranging and chaining of a line. Problem # 1. To erect, with a tape, a perpendicular to a chain line from a point on it: It can be done by forming a right angled triangle by taking three sides of a triangle in the proportion of 3, 4 and 5. [...]
The limit of length of the offset is below 15 and should not increase 15 m if its direction is set simply by eye or by tape. However, the length of offset mainly depends upon: (i) The scale of the plan (ii) The accuracy desired (iii) The maximum permissible error in eye judgement in laying out the direction of the [...]
After reading this article you will learn about the construction and classification of scale of a map. Construction of Scales of a Map: In plotting a survey, often an object to be represented on paper is so large that it would be inconvenient to make a full sized drawing of it. The drawing or map is then made to a [...]
The three main obstacles in chaining of a line are of the following types: 1. Chaining Free, Vision Obstructed 2. Chaining Obstructed, Vision Free 3. Chaining and Vision Both Obstructed. It sometimes happens that a survey line passes through some object such as a pond, a building, a river, a hedge etc. which prevents the direct measurement of that part [...]
There are two main types of the field-book: 1. Single Line Field-Book 2. Double line Field-Book. The field measurements, sketches and relevant notes are recorded for future reference in a note book, known as field-book. The field-book in general use is about 20cm * 12cm and opens length wise. Type # 1. Single Line Field-Book (Fig. 3.18, b): Every page [...]
Plotting means to represent on paper, to a suitable scale, the previously surveyed objects in accordance with their shape and size. Plotting is commenced after the field-work is over. The plotting of a chain survey is done in the following steps: (i) A suitable scale is chosen before starting the plotting work. The scale depends upon the importance of the [...]
This article throws light upon the top five instruments that are used for setting out right angles and finding the foot of perpendicular from the object on the lines. The instruments are: 1. Cross Staff 2. Optical Square 3. Prism Square 4. Offset Rod 5. Measuring Tape. Instrument # 1. Cross-Staff: It is generally found in two patterns: (i) Open [...]
After reading this article you will learn about:- 1. Definition of Chain Surveying 2. Principle of Chain Surveying 3. Equipment 4. Execution 5. Terms. Definition of Chain Surveying: It is the method of surveying in which the area is divided into network of triangles and the sides of the various triangles are measured directly in the field with chain or [...]
The offsets are classified according to direction and length, according to direction it is of two types i.e., perpendicular offsets and oblique offsets, according to length i.e., short offsets and long offsets. 1. According to Direction: (i) Perpendicular offsets, and (ii) Oblique offsets. (i) Perpendicular Offsets: The distances measured at right angles to the chain line from the objects are [...]
Get the answer of: How to book Field–Notes ? (i) Booking is commenced at the bottom of the page and worked upwards and carried continuously through the successive pages so that while writing, the centre line of the book and the chain on the ground correspond with the Surveyor's own direction. (ii) The number or name of the line and [...]