Open and Closed Traverse and Their Application to Engineering Problems
Traverse surveying is a method in which a series of connected lines are measured in terms of their lengths and directions. These lines form a framework used for mapping and layout work. Traverses are broadly classified into open traverse and closed traverse. In ITI Draughtsman Civil, understanding these types and their applications is essential for solving engineering problems.
1. Traverse Survey
A traverse consists of a number of straight lines connected together, where the length and direction of each line are measured. The endpoints of these lines are called stations.
2. Open Traverse
Definition
An open traverse is a series of connected survey lines that do not form a closed figure. It starts from a known point and ends at an unknown point.
Characteristics
- Does not return to the starting point.
- No direct method of checking accuracy.
- Suitable for route surveys.
Applications
- Road alignment surveys.
- Railway line surveys.
- Canal and pipeline surveys.
- Transmission line surveys.
3. Closed Traverse
Definition
A closed traverse is a series of connected lines that form a closed polygon. It either starts and ends at the same point or closes on another known point.
Types of Closed Traverse
- Loop Traverse: Starts and ends at the same point.
- Link Traverse: Starts and ends at different known points.
Characteristics
- Forms a closed figure.
- Allows checking of accuracy through angular and linear closure.
- Provides more reliable results.
Applications
- Boundary surveys.
- Property and land surveys.
- City and town planning.
- Construction layout of buildings.
4. Difference Between Open and Closed Traverse
| Open Traverse | Closed Traverse |
|---|---|
| Does not form a closed figure. | Forms a closed polygon. |
| No check on accuracy. | Accuracy can be checked. |
| Less reliable. | More reliable. |
| Used for route surveys. | Used for boundary and area surveys. |
5. Application to Engineering Problems
Traverse surveying plays a significant role in solving various engineering problems:
- Road and Railway Alignment: Open traverse is used to determine the route.
- Land Measurement: Closed traverse helps in calculating area.
- Construction Layout: Used for setting out buildings and structures.
- Mapping: Helps in preparing topographical maps.
- Infrastructure Projects: Used in pipelines, canals, and power lines.
6. Importance in Surveying
- Provides framework for mapping and design.
- Ensures accurate measurement of distances and directions.
- Helps in solving practical engineering problems.
Precautions
- Ensure accurate measurement of angles and distances.
- Check for errors in closed traverse.
- Maintain proper field records.
Role of Draughtsman Civil
A Draughtsman Civil uses traverse data to prepare plans, layouts, and maps. Understanding open and closed traverse helps in accurate plotting and solving engineering design problems.
Conclusion
Open and closed traverses are important methods in surveying. Each has its own characteristics and applications in engineering projects.
For ITI Draughtsman Civil students, knowledge of these traverses is essential for accurate surveying and successful construction planning.