CE 515 Railroad Engineering Operations of Railways “Transportation exists to conquer space and time -”

Safety FRA responsible for safety Safety never deregulated All accidents reported Safety and Loss Control Department

Tracks Main tracks: governed by one or more methods of control. Should not be occupied without permission or authority Other than main tracks: occupancy without authority, the locomotive engineer should look for other movements, usually max 20mph

Speed Higher speed: improve capacity and productivity but also risk and maintenance cost Separate speed according to the type of train Temporary Speed Restrictions (TSR) and Permanent Speed Restrictions (PSR)

Rail Traffic Control Systems Track Warrant Control (TWC) Direct Traffic Control (DTC) Automatic Block Signal (ABS) Centralized Traffic Control (CTC)

Rail Traffic Control Systems TWC, DTC: Non-signalized systems Use radio communication and computers Rail Traffic Controller (RTC): order transferred by radio and written by crew

Automatic Block Signal (ABS) Series of consecutive blocks governed by block signals, cab signals, or both. Signals activated by a train moving through the block, or by certain conditions that affect the block use. Developed in 1872, Dr. William Robinson Divide “tracks” into blocks, only one train per block Directional operations, two or more tracks Designated current of traffic, low-density single tracks

Automatic Block Signal (ABS) Track circuit Fail-safe design Length of block: equal to longest normal stopping distance “Two-block, three-indication”, “Three-block, four-indication” Remained ABS systems: operated by TWC rules

Automatic Block Signal (ABS) http://www.youtube.com/watch?v=U8yGNKH2t3g

Centralized Traffic Control (CTC) Track territories, double track sections: crossing over is allowed. Rail Traffic Control Center: all track circuits connected, controlled together Panel: showing position of each train

Centralized Traffic Control (CTC) http://mysite.du.edu/~jcalvert/railway/ctc.htm

Centralized Traffic Control (CTC)

Centralized Traffic Control (CTC) Authority to enter a CTC main track: by signal. Crew requests for permission by radio Opposing movements: not allowed, only following train movements “Intermediate signals”: facilitate fleeting of trains

Centralized Traffic Control (CTC) Single track: 70% of capacity of double track with ABS Railways: shift to CTC: excess capacity

Questions?