Level II major construction a) construction of new track, signal, power supply and other operation equipment / systems or access to existing operation equipment / systems; b) Construction involving upgrading of trackside, on-board and central signal equipment; c) Construction involving upgrading of software and hardware at line level, central level and network level of communication system; d) Construction of large and medium-sized maintenance projects involving signal, power supply, track and other running equipment (Systems); e) It involves the construction of 110kV and above main substations that have been out of service for more than 24h, the consolidation of substation equipment, and the replacement of transformers and rectifier cabinets; f) Construction involving changes in operation mode and operation limit of train operation equipment / system G) construction involving partial shutdown of train operation equipment (line); h) Construction involving the introduction of new technologies and equipment related to driving; i) External construction involving buildings, bridges, pipelines, power communication lines and other external construction affecting train operation safety; j) Construction involving the closure of station entrances and exits, passages or more than one-third of the service area of the station during operation; k) Escalators in transfer stations and transfer channels (halls) need to be stopped for more than 24h for normal maintenance; l) AFC system, Fas / BAS system line level / central system level / network level maintenance, software and hardware upgrading, relocation, addition and demolition of chillers; m) Construction that needs to break through traffic safety protection measures and construction approval regulations; n) Other construction approved by the construction management team…
Except for emergency repair construction, class I major construction and class II major construction, other construction of daily maintenance construction are daily maintenance construction.
