The grade compensation of a 4° curve on a Broad Gauge railway track is
For BG track grade compensation is 0.04% per degree of curve. For 4° curve grade compensation will be
= 4 x 0.04 = 0.16 % .
In a BG railway track, the specified ruling gradient is 1 in 250. The horizontal curve of 3° on a gradient of 1 in 250 will have the permissible compensated gradient of
Grade compensation = 0.04 x 3 = 0.12%
Permissible gradient =
Grade compensation on curves in Indian Railways for BG is
What is curve resistance for a 50 tonnes train on a BG track on a 4° curve?
Curve resistance = = 0.08 tonne
Consider the following surveys:
1. Reconnaissance survey
2. Preliminary survey
3. Traffic survey
4. Location survey
The correct sequence in which these surveys are conducted before the alignment of a track is finalized, is
Preliminary survey is called initial location survey. Detailed survey is called final location survey.
Which one of the following is not related to theories of creep of rails?
Wave theory states that wave motion is set up by moving of wheels. A vertical reverse curve is formed in the rails ahead of the wheels, resulting from the rail deflection under the load, is the chief cause of creep.
Percussion theory states that the creep is due to impact of wheels at the rail end a head at joints. Though the creep is very small in single impact but cumulative effect of number of wheels in quick succession results in sufficient creep.
Drag theory states that backward thrust on driving wheels of the locomotive of train has got a tendency to push the sail off the track backward while the other wheels of the locomotive and the vehicles push the rail in the direction of travel. This results in creep of rails in the direction of movement of trains
The ‘track modulus’ is an index of measure of which of the following?
Track modulus is a measure of stiffness of the track and is defined as load per unit length of the rail, required to produce a unit depression in the track.
Which of the following factors help in ensuring track modulus, in a railway track?
The track modulus depends upon the gauge, the type of rails, the type and density of sleepers, the type of section of ballast and sub-grade.
What is the hauling capacity of a railway locomotive, carrying an axle load of 24 tonnes each? (Assume 0.166 as the coefficient of friction)
Hauling capacity = μ x W x n
= 0.166 x 24 x 4 = 15.936
= 16 tonnes
Consider the following factors:
1. Gauge length
2. Degree of the curve
3. Ruling gradient
4. Maximum allowable superelevation
Which of these factors determine the maximum permissible speed on BG railway tracks?
The maximum permissible speed on the railway track is limited by the speed on the curve:
(i) Maximum sanctioned speed.
(ii) Safe speed over the curve by martin’s formula depends upon gauge type and radius or degree of curve.
(iii) Transitive curve whether present or not.
(iv) Maximum allowable superelevation.