CONVENTIONAL SIGNS IN SURVEYING
(Civil Engineering)
1. Introduction
In surveying, conventional signs are standard symbols used in maps and plans to represent natural and man-made features.
Instead of drawing real objects, small symbols are used so that drawings remain:
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Clear
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Simple
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Easy to understand
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Uniform everywhere
2. Definition
Conventional signs are pre-decided graphical symbols used in surveying maps to show features like:
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Roads
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Buildings
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Rivers
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Trees
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Wells
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Railways
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Boundaries
3. Need for Conventional Signs
Conventional signs are used to:
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Save drawing time
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Avoid confusion
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Maintain uniformity
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Make maps readable
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Communicate information quickly
4. Types of Conventional Signs
Conventional signs are generally classified into:
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Signs for Natural Features
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Signs for Man-made Features
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Signs for Boundaries & Lines
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Signs for Water Features
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Signs for Transport & Communication
5. Common Conventional Signs with Explanation
5.1 Natural Features
| Feature | Symbol Meaning | Explanation |
|---|---|---|
| Tree | 🌳 (small circle with dots) | Represents a single tree |
| Forest | Group of tree symbols | Shows wooded area |
| Hill | Concentric curved lines | Shows raised land |
| Contours | Closed curves | Show height & slope |
| Marshy land | Short grass marks + water lines | Indicates swamp |
5.2 Water Features
| Feature | Symbol Meaning | Explanation |
|---|---|---|
| River | Wavy double line | Flowing water |
| Canal | Straight parallel lines | Man-made waterway |
| Pond/Tank | Closed irregular shape | Stored water |
| Well | Small circle with “W” | Drinking water source |
| Bridge | Thick line across river | Crossing |
5.3 Man-Made Features
| Feature | Symbol Meaning | Explanation |
|---|---|---|
| Building | Solid rectangle | House or structure |
| Temple | Small square with flag | Religious place |
| School | Rectangle + “Sch” | Educational building |
| Hospital | Cross sign | Medical facility |
| Factory | Rectangle with chimney | Industrial building |
5.4 Transport & Communication
| Feature | Symbol Meaning | Explanation |
|---|---|---|
| Road (metalled) | Double solid line | Paved road |
| Road (unmetalled) | Double broken line | Mud road |
| Railway | Line with cross sleepers | Railway track |
| Footpath | Dotted line | Pedestrian way |
| Culvert | Small bridge symbol | Drain crossing |
5.5 Boundaries & Lines
| Feature | Symbol Meaning | Explanation |
|---|---|---|
| Property boundary | Long dashed line | Land limit |
| Fence | Short vertical ticks | Enclosure |
| Hedge | Small bush marks | Natural boundary |
| Survey line | Thin straight line | Measured line |
6. Examples of Use
Example 1 – Village Map
In a village survey map:
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Houses → rectangles
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Roads → double lines
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Temple → flag symbol
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Pond → irregular closed shape
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Trees → small circles
Anyone reading the map can understand the village layout easily.
Example 2 – Highway Project Map
For road construction:
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Existing road → double thick line
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Culvert → special bridge mark
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Electric poles → small circle + cross
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Trees → circle symbols
This helps engineers decide where to widen the road.
Example 3 – Land Record Map
In land records:
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Field boundaries → dashed lines
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Well → circle with W
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Farm house → solid square
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Canal → parallel lines
This avoids disputes and gives legal clarity.
7. Advantages of Using Conventional Signs
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Saves space on drawing
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Easy to draw
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Internationally understood
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Avoids lengthy written descriptions
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Improves professional quality of maps
8. Important Points for Exams
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Conventional signs are standard symbols
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They represent real features in simplified form
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Used in survey maps, plans, and topographic sheets
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Must be drawn neatly and correctly
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Always explained in a legend (index)
9. Difference Between Conventional Signs and Legends
| Conventional Signs | Legend |
|---|---|
| Symbols on map | Explanation of symbols |
| Used in drawing | Written beside map |
| Visual | Descriptive |