Construction Gauge

The construction gauge is decided by adding the necessary clearance to the loading gauge so that vehicles can move safely at the prescribed speed without any infringement. The various fixed structures on railway lines such as bridges, tunnels, and platform sheds are built in accordance with the construction gauge so that the sides and top remain clear of the loading gauge.


Three types of track gauges have been adopted in Indian Railways. The basic consideration behind the adoption of the metre gauge and narrow gauge was to provide access to undeveloped areas with low cost of construction. The multiple-gauge system has caused many problems and caused serious bottlenecks in the operation of the Railways. The work of gauge conversion has been accelerated on Indian Railways since 1992. The uni-gauge system will be highly beneficial to rail users, the railway administration, and the nation.

Review Questions

1. Define gauge problems with special reference to Indian Railways and bring out the effects of variations in the width of the gauge.

2. Why is it desirable to have, as far as possible, a uniform gauge for the railway network of a country?

3. What is the standard gauge in Indian Railways? State the disadvantages of having a multiple gauge system.

4. List out the various gauges prevailing in India with their gauge widths. What factors govern the selection of a suitable gauge? Discuss.

5. What is the uni-gauge policy of Indian Railways? Describe the benefits of the uni-gauge system.

6. What do you understand by loading gauge? How is it different from the construction gauge?

7. How many gauges exist in Indian Railways? Give their widths and route kilometres.

8. Write short notes on the following.

(a) Break of gauge (b) Standard gauge

(c) Cape gauge (d) Metre gauge


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