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Virtual Block Track Circuit Assessment Report

Document Series
Technical Reports
Report Number
Subject Communications, Train Control
Virtual block track circuit, VBTC, Positive train control, PTC, Quasi-Moving block, QMB, Higher reliability and capacity train control, HRCTC, Virtual block

The Federal Railroad Administration (FRA) sponsored Transportation Technology Center, Inc. (MxV Rail), in collaboration with a railroad technical advisory group (TAG), to research and conduct proof-of-concept field testing of a Virtual Block Track Circuit (VBTC) concept. The VBTC concept uses track circuit-based detection methods to divide conventional physical signal blocks into multiple virtual blocks, without adding wayside devices at virtual block boundaries or modifying the current Positive Train Control (PTC) onboard system. The team conducted research and field studies using a supplier’s product at the Transportation Technology Center (TTC) located in Pueblo, Colorado, from June to September 2022. Researchers concluded that VBTC has the potential to reduce train headways and increase rail network capacity.

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Last updated: Friday, December 8, 2023