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Welded rails still expand without gaps at every joint

Modern continuously welded railway track replaces many of the joints that create the familiar clickety-clack of older rails. The steel still expands with heat, but restraint from the track structure turns much of that tendency into internal forces. Explore how a chosen stress-free temperature balances hot-weather compression against cold-weather tension.

5–7 min

Questions you could explore

  • Why is the temperature of the rail more informative than the air temperature alone?
  • How do restraint and rail temperature affect the forces in continuously welded track?

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Welded rails still expand without gaps at every joint | Speech Topic | speaking.app