Home / Standards / GB/T 39559.4-2020 GB/T 39559.4-2020 Active Specifications for operational monitoring of urban rail transit facilities—Part 4: Track and earthworks 城市轨道交通设施运营监测技术规范 第4部分:轨道和路基 Standard Type GBT ICS 03.220.20 CCS P51 Status 现行 Issue Date 2020-12-14 Implementation 2021-07-01 Responsible Dept 交通运输部 Drafting Unit N/A