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From page 57... ... SECTION 11 57 Conclusion Many mass transit agencies are now using or considering CBTC technology to equip their new lines or to upgrade their existing systems. Among the numerous benefits of CBTC, the main attractive feature for agencies is the possibility to increase their system capacity by reducing the headway between trains. This capacity increase is accompanied by other benefits such as continuous speed control, more flexible operation, and less equipment installed on the roadbed and thus less wayside maintenance. Although conventional signaling systems could technically provide similar headway to CBTC, they would require more wayside equipment to be deployed which results in more installation work and wayside maintenance needed. Minimizing wayside equipment is hence an additional factor in the decision to implement CBTC technology. This guide has been developed for transit agencies which have already decided or are considering CBTC technology. Attention should be given to the need for a possible secondary system because a system that includes both CBTC and a secondary system may result in an overly complicated system harder to deploy and to maintain than anticipated. The guide describes the different levels of secondary systems used in CBTC projects. Some projects have successful operation without any secondary system at all. Some have secondary systems capable of managing a single non‐CBTC train (train with CBTC failure or non‐equipped work train) while other projects are capable of some level of revenue service. Choosing more capabilities from the secondary system results in more adverse effects on the deployment effort and maintenance, and on the availability of the CBTC system. On the other hand, having no STD/PS requires the transit agency to rely on operating procedures alone during system failures and further restricts the operation of unequipped work trains.  The work train issue may be included as a factor for secondary system selection, or the secondary system selection may be a factor on whether to equip the work trains. There are examples of projects without a secondary system where non‐equipped work trains have been managed successfully. Equipping work trains is recommended when there is no secondary system and revenue service operation is 24/7; this avoids frequent operation of CBTC and non‐CBTC trains at the same time. Read the entire page →
From page 58... ... SECTION 11 – CONCLUSION 58  When it is decided that no back‐up for revenue service is needed, assess the need for managing a single train with CBTC failure and/or non‐equipped work train. The industry survey showed that there is a recent trend to be able to manage a single train and/or non‐equipped work train with STD/PS.  There are different methods of implementation based on the performance of the STD/PS to manage non‐CBTC trains. The STD/PS can manage, with limited operating procedure, one train per interstation, or one train between interlockings; or it can simply track the non‐CBTC trains for other trains to continue running in CBTC mode around the train with CBTC failure. Read the entire page →

From page 57...

... SECTION 11 57 Conclusion Many mass transit agencies are now using or considering CBTC technology to equip their new lines or to upgrade their existing systems. Among the numerous benefits of CBTC, the main attractive feature for agencies is the possibility to increase their system capacity by reducing the headway between trains. This capacity increase is accompanied by other benefits such as continuous speed control, more flexible operation, and less equipment installed on the roadbed and thus less wayside maintenance. Although conventional signaling systems could technically provide similar headway to CBTC, they would require more wayside equipment to be deployed which results in more installation work and wayside maintenance needed. Minimizing wayside equipment is hence an additional factor in the decision to implement CBTC technology. This guide has been developed for transit agencies which have already decided or are considering CBTC technology. Attention should be given to the need for a possible secondary system because a system that includes both CBTC and a secondary system may result in an overly complicated system harder to deploy and to maintain than anticipated. The guide describes the different levels of secondary systems used in CBTC projects. Some projects have successful operation without any secondary system at all. Some have secondary systems capable of managing a single non‐CBTC train (train with CBTC failure or non‐equipped work train) while other projects are capable of some level of revenue service. Choosing more capabilities from the secondary system results in more adverse effects on the deployment effort and maintenance, and on the availability of the CBTC system. On the other hand, having no STD/PS requires the transit agency to rely on operating procedures alone during system failures and further restricts the operation of unequipped work trains.  The work train issue may be included as a factor for secondary system selection, or the secondary system selection may be a factor on whether to equip the work trains. There are examples of projects without a secondary system where non‐equipped work trains have been managed successfully. Equipping work trains is recommended when there is no secondary system and revenue service operation is 24/7; this avoids frequent operation of CBTC and non‐CBTC trains at the same time.

Read the entire page →

From page 58...

... SECTION 11 – CONCLUSION 58  When it is decided that no back‐up for revenue service is needed, assess the need for managing a single train with CBTC failure and/or non‐equipped work train. The industry survey showed that there is a recent trend to be able to manage a single train and/or non‐equipped work train with STD/PS.  There are different methods of implementation based on the performance of the STD/PS to manage non‐CBTC trains. The STD/PS can manage, with limited operating procedure, one train per interstation, or one train between interlockings; or it can simply track the non‐CBTC trains for other trains to continue running in CBTC mode around the train with CBTC failure.

Read the entire page →

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