(1) Opening time

This line: December 28, 2018 (Northeast Loop); December 30, 2019 (Southwest Loop); January 20, 2021 (Remaining section for forming the loop).

Interconnection: On September 18, 2020, cross-line operation between Line 4 and the Loop Line and co-line operation on the ground of Lines 5 and 10 for interconnection were launched; on December 28, 2021, cross-line operation among Lines 4, the Loop Line and 5 for interconnection was launched.

(2) Project overview

The total length of the Chongqing Ring Line is 50.802 kilometers, with a total of 66 trains.

(3) Technical solutions and their advantages and characteristics

Chongqing Loop Line: It adopts the CBTC system based on interconnection and interoperability. Chinese wisdom has solved the world-class problem of interconnection and interoperability of urban rail transit.

● Formulate a complete set of technical standards for the interconnection and interoperability of the signaling system: unify the signaling interfaces of different manufacturers, and establish interconnection interface standards and operation scenario specifications.

● Build a communication architecture that supports interconnection and interoperability among multiple manufacturers: Adopt the HSS solution to address the cross-line communication problem and enable cross-line trains to operate without degradation or stopping under the CBTC mode.

● Build an interconnected CBTC system test platform: Build an on-vehicle adaptation system to meet the test requirements and ensure the safe and reliable operation of the system. At the same time, build a global scheduling system to achieve the sharing of train operation information across the network, the compilation and management of train operation diagrams, and the overall coordination of operations.

(4) Project performance

● Owner's evaluation: The advantages of interconnected and networked operation have been widely recognized. On the Chongqing Rail Transit, cross-line operation among Lines 4, Ring Line and Line 5 has been achieved, saving passengers 33 minutes of travel time. The project has been strongly promoted by Chongqing Rail Transit (Group) Co., Ltd. and has achieved interconnection and interoperability in many cities such as Qingdao and Hohhot.

● Expert evaluation: The demonstration application has achieved remarkable economic and social benefits, strongly promoted the engineering and industrialization development of the interconnected signaling system with China's independent intellectual property rights, and is conducive to enhancing China's international status in the field of urban rail transit. The overall technology of the project is at the international leading level and has broad application and promotion value.

(5) Project Honors

● In 2015, the National Development and Reform Commission approved the "Demonstration Project for Interoperability of Chongqing Rail Transit Signaling Systems".

● In 2018, the China Urban Rail Transit Association took the lead in releasing the English version of Guidelines for the Interoperability Construction of CBTC Signal Systems for Rail Transit.