CTB Track Systems & Components Flashcards

What is a rail anchor primarily used for?

Answer: To resist longitudinal rail movement (rail creep) caused by train braking and acceleration forces

Rail anchors clip onto the rail base and bear against the tie to resist longitudinal movement from train traffic forces.

The term 'ballast section' refers to:

Answer: The cross-sectional profile of ballast, including shoulder width, depth under ties, and side slopes

A ballast section defines the required geometry of ballast placement, including minimum depth under ties, shoulder width, and slope angle.

What is the primary purpose of elastic (spring) rail clips used in concrete tie track?

Answer: To hold the rail to the tie while allowing controlled longitudinal movement and providing electrical isolation

Elastic clips apply a controlled toe load to the rail foot, securing it to the concrete tie while accommodating thermal expansion and providing vibration damping.

A 'derail' device is installed on a track to:

Answer: Intentionally derail unauthorized or runaway equipment to protect the main line or other assets

A derail is a safety device that diverts wheels off the rail to stop unintended movement and protect mainline traffic or other personnel.

What does 'cross-level' measure in track geometry inspections?

Answer: The difference in elevation between the two rails at any given point, measured perpendicular to the track

Cross-level is the elevation difference between the two rail tops across the track, and excessive cross-level can cause rocking or rollover of equipment.

What is the function of a tie plate in wood-tie track construction?

Answer: To distribute rail load over a larger tie surface area and maintain rail cant

Tie plates spread the concentrated rail load over more of the tie's bearing area and include a built-in 1:40 cant to correctly orient the rail head.