Train Driver Track and Infrastructure Knowledge 2 — Questions and Answers
Question 1: What is the purpose of 'tie plates' in railroad track construction?
- To distribute rail load over the tie and maintain proper rail cant (Correct answer)
- To fasten the rail to the tie using spikes only
- To protect the tie from weather and decay
- To align the rail gauge at turnout locations
Correct answer: To distribute rail load over the tie and maintain proper rail cant
Tie plates sit between the rail base and the wooden tie, distributing load over a wider area and providing a slight inward cant to the rail.
Question 2: What is a 'thermal sun kink' and when is it most likely to occur?
- A lateral track buckle caused by rail expansion in high heat, most common in summer (Correct answer)
- A vertical track deformation from heavy axle loads in cold weather
- A rail crack caused by rapid temperature changes in spring
- A tie failure resulting from ground heave during winter thaw
Correct answer: A lateral track buckle caused by rail expansion in high heat, most common in summer
Sun kinks occur when continuously welded rail expands beyond its capacity in extreme heat, causing lateral buckling of the track.
Question 3: What does a yellow flag displayed by a track worker indicate to an approaching train?
- Reduce speed to the prescribed limit — workers or equipment are in or near the track (Correct answer)
- Stop immediately — the track is blocked
- Proceed normally — the worker is clear of the track
- Increase speed to clear the work zone quickly
Correct answer: Reduce speed to the prescribed limit — workers or equipment are in or near the track
A yellow flag is a slow order signal requiring trains to reduce speed through the flagged work zone.
Question 4: What is the purpose of 'ballast' in railroad track construction?
- To support ties, provide drainage, distribute load, and maintain track geometry (Correct answer)
- To increase friction under the wheels during wet conditions
- To prevent animals from walking between the rails
- To insulate the rails electrically from the ground
Correct answer: To support ties, provide drainage, distribute load, and maintain track geometry
Ballast (crushed stone or gravel) supports the ties, drains water away from the track structure, and distributes the load from trains to the subgrade.
Question 5: What does a 'drawbar' connect on a locomotive consist?
- Two locomotive units when a conventional coupler is not used between them (Correct answer)
- The locomotive to the lead passenger car
- The coupler to the locomotive frame
- The fuel tender to the steam locomotive
Correct answer: Two locomotive units when a conventional coupler is not used between them
A drawbar is a rigid or semi-rigid connection between two locomotive units, used instead of a standard knuckle coupler for a permanent or semi-permanent connection.
Question 6: What is the significance of a 'joint bar' (angle bar) in railroad track?
- It connects the ends of two rails at a joint to maintain alignment and transfer load (Correct answer)
- It is the mounting point for wayside signal equipment
- It reinforces turnout frog points against wear
- It connects the rail to the tie plate at every fastener
Correct answer: It connects the ends of two rails at a joint to maintain alignment and transfer load
Joint bars are bolted to both sides of the rail web at rail ends, holding rails in alignment and transferring load across the joint.
Train Driver Track and Infrastructure Knowledge 2
What is the purpose of 'tie plates' in railroad track construction?