2) Precautionary measures of collision
The signal system of high-speed wheel-rail railway
entirely fulfills the function of precautions against colliding.
Signal system mainly consists of centralized traffic center
(CTC), station computer interlocking system (CIS), train
operation control system (OCS), special block system,
special communication equipment, and so on. Fig2 displays
configuration of signal system in France.
CTC centers of high-speed railway are set according to
lines’ arrangement. The main function of CTC center is to
centralize command of all trains to run according to train’s
running situation and schedule. The TGV adopts TVM430
train automatic control system, while ground information
transmission adopts UM2000 jointless track circuit, Its work
principle:
Train’s running use fixed block mode. Namely divide
railway line into many fixed sections according to space
relationship. These sections are separated each other
electrically and every section allows only one train to run.