Home / Standards / GB/T 1231-2024 GB/T 1231-2024 Active High strength bolts with large hexagon head assemblies for steel structures 钢结构用高强度大六角头螺栓连接副 Standard Type GBT ICS 21.060.10;21.060.20;21.060.30 CCS J13 Status 现行 Issue Date 2024-09-29 Implementation 2025-04-01 Responsible Dept 中国机械工业联合会 Drafting Unit N/A